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PLOS One logoLink to PLOS One
. 2021 Feb 12;16(2):e0246300. doi: 10.1371/journal.pone.0246300

Running behaviors, motivations, and injury risk during the COVID-19 pandemic: A survey of 1147 runners

Alexandra F DeJong 1,*,#, Pamela N Fish 1,#, Jay Hertel 1,#
Editor: Daniel Boullosa2
PMCID: PMC7880469  PMID: 33577584

Abstract

The COVID-19 pandemic has influenced activity behaviors worldwide. Given the accessibility of running as exercise, gaining information on running behaviors, motivations, and running-related injury (RRI) risk during the pandemic is warranted. The purpose of this study was to assess the influence of the COVID-19 pandemic on running volume, behaviors, motives, and RRI changes from the year prior to the pandemic to the timeframe during social isolation restrictions. Runners of all abilities were recruited via social media to complete a custom Qualtrics survey. Demographics, running volume, behaviors, motivations, and injury status were assessed for the year prior to the pandemic, and during social isolation measures. Descriptive statistics and Student’s t-tests were used to assess changes in running outcomes during the pandemic. Logistic regressions were used to assess the influence of demographics on running behaviors and injury. Adjusted RRI risk ratios were calculated to determine the odds of sustaining an injury during the pandemic. Alpha was set to.05 for all analyses. A total of 1147 runners (66% females, median age: 35 years) across 15 countries (96% United States) completed the survey. Runners reported increased runs per week (Mean Difference with Standard Error [MD]: 0.30 [0.05], p < .001), sustained runs (MD: 0.44 [0.05], p < .001), mileage (MD: 0.87 [0.33], p = .01), and running times of day (MD: 0.11 [0.03], p < .001) during the pandemic, yet reported less workouts (i.e. sprint intervals; MD: -0.33 [0.06], p < .001), and less motives (MD [SE]: -0.41 [0.04], p < .001). Behavior changes were influenced by running experience and age. There was 1.40 (CI: 1.18,1.61) times the RRI risk during the pandemic compared to prior to the social isolation period. The COVID-19 pandemic influenced runners’ behaviors with increased training volume, decreased intensity and motivation, and heightened injury risk. These results provide insights into how physical activity patterns were influenced by large-scale social isolation directives associated with the pandemic.

Introduction

Running is one of the most popular forms of physical activity worldwide, and is an easily accessible form of exercise as there are minimal equipment and sport structure requirements [1]. According to the most recent report from the International Association of Athletics Federation, running races attracted over 107.9 million racers across 70,000 events in 2019, and running popularity has grown by approximately 60% over the past decade [2]. Running offers extensive health benefits, including decreased risk of chronic diseases [3] and improved mental health [4, 5], making this form of exercise an appealing health behavior for the general population. Additionally, many runners may opt to train in groups, clubs, or teams, thus introducing a social aspect to the activity [6].

The severe acute respiratory syndrome coronavirus 2, or the COVID-19, pandemic has imposed a unique and sweeping demand worldwide with government directives requiring the public to perform self-isolation behaviors and limit interpersonal exposures to mitigate the spread of this deadly virus. These wholesale changes have led to gym and exercise training facility closures, termination of formal and informal group activities, and restrictions on parks and trails that disrupted the norms of the distance running community. The COVID-19 pandemic has additionally led to many race cancellations or postponements that inevitably will result in training changes for competitive athletes [7]. However, there is currently no information available on how the pandemic has influenced running training behaviors, particularly in regards to running volume, intensity, training surfaces, and motives for engaging in running activities.

Another cogent concern associated with the COVID-19 pandemic is how the resultant shifts in running behavior and training schedules will influence the rates of running-related injury (RRI). Despite the aforementioned health benefits and motives associated with running as exercise, RRI’s have long posed a substantial burden on the running community. Previous epidemiological research studies have found RRI incidence rates are as high as 90% of the running population, with the majority localized to the lower extremity [8, 9]. Up to 75% of injuries have additionally been categorized as overuse or recurrent pathologies primarily attributed to training errors [10, 11], such as sudden increases in running volume and intensity [12, 13]. The COVID-19 presents a unique external pressure on the running community and is likely to affect the injury occurrence in this population with necessary training adaptations. As such, interpreting how the pandemic is currently influencing running behaviors and RRI rates is critical for the greater community and for health care professionals treating runners in clinical settings. Data on RRI’s would help clinicians prepare for patient volumes following re-opening and lifted restrictions on social isolation measures, and help to inform return to activity and injury prevention programming by assessing potential detraining or over-training indicators [12]. Clinicians may also be able to use information on running behaviors and running motivations to best inform future telemedicine programs [6].

The purpose of this study was to assess the effects of the COVID-19 pandemic on running behaviors among adult male and female runners of all experience and participation levels. Specifically, we aimed to assess running volume, running behaviors, motives for running, and RRI change from the year prior to the pandemic to the timeframe during social isolation restrictions. We hypothesized that overall, runners would present with increased running volume due to the accessibility of running as exercise, coupled with decreased running intensity due to changes in training goals and lack of access to tracks or training gyms. We additionally hypothesized that runners’ motivations would be decreased during from before to during the pandemic. We anticipated that changes in running behaviors and motives would be dependent upon participant demographics, including age, sex, geographical location, and experience levels. In terms of injury risk, we hypothesized that there would be more RRI’s localized to the lower extremity during the pandemic compared to before social isolation efforts due to acute changes in training.

Materials and methods

Participants

Adult male and female runners were recruited via social media outlets to complete an online survey (Qualtrics Labs Inc.). Participants were required to be at least 18 years of age, and either currently running or had been running within the last year at any participation and experience level. All respondents provided written consent to complete the survey prior to participation, and the study protocol was approved by the University of Virginia Institutional Review Board for Social and Behavioral Sciences IRB-SBS #3677.

Survey instrument

The survey was developed in English by two researchers, and piloted among a group of 10 runners of varying age levels to determine face validity and refine the questions to improve clarity. The survey took approximately 10 minutes to complete, and the main components of the survey included participant demographics, running volume, behaviors, motives, and RRI’s in the year prior to the COVID-19 pandemic, and running volume, behaviors, motives, and RRI’s during the COVID-19 pandemic (S1 File).

The survey included demographic questions regarding age, biological sex, geographical location, and running experience. The remaining questions were posed both in the context of the year prior to social distancing restrictions in participants’ geographical region due to the COVID-19 pandemic, and in the time during social distancing restrictions in participants’ geographical region due to the COVID-19 pandemic. Only the year prior to the pandemic was used to minimize recall bias and reflect running training without capturing recent fluctuations in training cycles. Running volume was assessed by asking the participants’ typical number of total runs per week, number of sustained runs per week, number of workouts per week (i.e. speed intervals, fartleks, tempo runs, hill repetitions, etc.), weekly mileage, and number of cross-training activities per week (i.e. strength training, cycling, swimming, yoga). Running behaviors were assessed by asking the participants’ typical running pace during sustained runs and workouts, primary running locations (indoors, outdoors, both), use of technology to track runs, and typical time of day for training (early morning [5-7AM], mid-morning [8-10AM], midday [11AM-1PM], early afternoon [2-4PM], afternoon [5-7PM], evening [8-10PM], night [11PM-4AM]).

Running motives were assessed using a checklist for all reasons that the participants felt were applicable, and included exercise/fitness, competition/races, socialization, stress relief, enjoyment/pleasure, and to occupy free time. Several additional questions were included when assessing running behaviors and motivations during the COVID-19 pandemic to assess how much participants subjectively felt their training had changed on a 9-point scale ranging from “increased a great deal” to “decreased a great deal”, and how concerned they were about their overall training and training goals on 5-point scales ranging from “very concerned” to “not concerned at all”. Participants were also offered an optional open-ended section to provide any comments on how the COVID-19 pandemic affected their running that was not captured in the structured questions.

To assess RRI status, participants were asked if they had suffered from any RRI’s (yes/no). We did not define RRI explicitly in the survey, however this was left intentionally broad to capture all injury data and became more specific in subsequent questions. Specifically, follow-up questions asked about the number of injuries they incurred, length of time taken off from running due to injury, length of time running training was modified due to injury, and chart to designate which body parts were affected (toe, foot, ankle, lower leg, knee, thigh, hamstring, hip, groin, abdomen, low back) by injury type (sprain [ligament], strain [muscle], fracture [broken bone], other [explain]).

Procedures

Adult runners were recruited to complete the online survey as a sample of convenience using a snowball sampling strategy. The survey link was initially distributed by the research team through personal and laboratory social media platforms (Twitter, Facebook, Instagram, LinkedIn, National Athletic Trainers’ Association GATHER webpage). Others were encouraged to share the link via their own social media accounts to forward the survey to others who may qualify and be interested in participating. The link was also shared via email to other researchers and running club coordinators. Recruitment originated in the United States; however, runners were encouraged to participate regardless of geographical location. The survey was available from May 4th to June 4th of 2020 to capture the time period during peak social isolation restrictions in North America.

Data processing

Only complete responses were included in analyses. In order to assess changes in training volume variables, the reported values pertaining to behaviors in the year prior to the pandemic were subtracted from outcomes during the pandemic. In order to prepare for logistic regression analyses, demographic and running behavior data were binned as follows: age (18–25, 26–35, 36–45, 46–55, 56+ years), experience (0–3, 4–10, 11–15, 16–20+ years), and geographical location (US East Coast, US Mid-West, US West Coast, UK and Ireland, Canada, Other Regions). Running behavior outcomes were categorized as increased, decreased, or no change within 1 unit when assessing the change pre- to during the pandemic in number of total runs, sustained runs, workouts, cross-training, motives, and running times of day. Mileage was categorized in a similar manner within 10 miles per week, and pace within 30 seconds.

Statistical analyses—Running behaviors and motives

Descriptive summary statistics were used to assess participant demographics, including biological sex, age, running experience in years, and geographical location. Descriptive statistics were additionally used to assess reported running behaviors prior to and during the pandemic, including number of total weekly runs, sustained runs, workouts, cross-training, weekly mileage, running pace, and use of technology to track runs. Histograms were used to visually assess data for normality, and the outcomes were observed to be normally distributed, supporting further analysis approaches. Student’s t-tests were subsequently used to determine if there were statistically significant differences in numbers of reported runs (including run sub-types), number of motives, number of running time(s) of day, weekly mileage, and running pace during the pandemic as compared to prior behaviors. Alpha was set a priori to.05 for all analyses. Running motives, typical running time(s) of day, and running locations were evaluated by response type prior to and during the pandemic.

Multivariate logistic regression analyses were used to assess the influence of demographic factors on running behaviors during the pandemic compared to before. Demographic factors were first assessed in isolation and considered for inclusion into the final regression model were biological sex, and the binned age, years of running experience, the interaction between age and sex, the interaction between age and experience, and geographical location factors. Running behaviors included the binned change in number of total runs, sustained runs, workouts, motives, running times of day, and mileage. Cross-training and pace were not included into the model given that the Student’s t-tests comparisons were not significantly different. Preliminary analyses reflected that there was not a significant age by sex interactions nor an age by experience interaction for any outcome and thus were not included in the overall model. Additionally, preliminary results reflected that there were not enough observations in the UK/Ireland, Canada, and other geographic categories to appropriately run the analyses, and subsequently only US regions were included. The final logistic regression models assessed the influence of age, sex, running experience, and US geographical regions on running behaviors.

Statistical analyses—Running-related injuries

Descriptive analyses were used to summarize the number of RRI’s, location of injury, and length of time training was affected due to injury prior to and during the pandemic among the participant pool that reported RRI’s. To assess RRI risk during the pandemic compared to before, an adjusted injury risk ratio was calculated using Eq 1. Given that social isolation took place primarily over three months, the percentage of injury prior to the pandemic was divided by four, and put into the model.

InjuryRiskRatio=([Adjusted#InjuriesPriortoPandemic/TotalRespondents]*100)([#InjuriesDuringPandemic/TotalRespondents]*100) (1)

Binary logistic regression analysis was used to assess the influence of demographic and training factors on injury occurrence during the pandemic. Demographic factors included into the regression model were biological sex, age, years of running experience, difference in mileage, difference in number of runs, and change in running location. Injury status in the past year was included as a covariate in the model given the influence of past injury on future injury risk.

Statistical analyses—Response themes and additional outcomes

The short responses collected from the study procedures were assessed using an inductive qualitative approach to elucidate response themes. First, open coding was performed in R (R Development Core Team, 2011) to identify recurring words within all survey responses, in which participants’ written responses were input into the coding platform and frequently appearing words were output along with the frequency count for each of these words. Two reviewers discussed open coding outcomes to help categorize responses into themes, and then independently evaluated all responses to label responses based upon the open coding results. The labeling process was continued until all responses were categorized into the most appropriate thematic bins, and the reviewers then re-convened to compare labels and resolve any discrepancies. In the event of any labeling discrepancies, the results were discussed amongst the study team until a consensus was reached. Finally, descriptive statistics were used to assess participants’ perceptions of the pandemic’s influence on their running training and goals.

Results

Running behaviors and motives

There were a total of 1147 complete responses recorded across 46 states and 15 countries, the majority of which coming from the United States due to the convenience sampling methods (Fig 1A and 1B). Respondents were primarily females (66%), the median age of respondents was 35 years, and the median length of running experience was 7–8 years (Fig 2). Descriptive outcomes and outcomes of the Student’s t-tests comparing running volume, pace, running behaviors, and use of running tracking technology prior to and during the pandemic can be found in Table 1. Overall, total number of runs, number of sustained runs, mileage, and running times of day significantly increased during compared to before the pandemic, however the total number of workouts per week and running motives significantly decreased (Table 1, Fig 3A and 3B). Changes in activity by state and by country can be found in S1A–S1F Fig.

Fig 1.

Fig 1

Responses (A) by state and (B) by country. Full List of Respondents—Australia (<1%), Brazil (<1%), Cayman Islands (<1%), Canada (1%), Denmark (<1%), Germany(<1%), Greece(<1%), Hong Kong(<1%), Ireland (<1%), Mexico (<1%), Netherlands (<1%), Russia (<1%), United Arab Emirates (<1%), United Kingdom (1%), United States (96%). List of missing states: Alaska, Mississippi, Montana, West Virginia.

Fig 2. Descriptive outcomes for respondents by sex, years of running experience, and age.

Fig 2

Percentage of male and female respondents, extent of running experience, and age distribution of respondents depicted across the figure graphics. Greater number of respondents per category is depicted in darker shades of blue for experience and age histograms.

Table 1. Mean outcomes and student’s t-test comparisons on running behaviors before and during the pandemic.

Before the Pandemic During the Pandemic Mean Difference (Standard Error) P-Value
Mean (95% CI) Mean (95% CI)
Total Runs Per Week (N) 4.27 ± 1.93 4.56 ± 1.92 0.30 (0.05) < .001*
Sustained Runs Per Week (N) 3.25 ± 1.78 3.69 ± 1.90 0.44 (0.05) < .001*
Workout Runs Per Week (N) 1.60 ± 1.5 1.93 ± 1.54 -0.33 (0.06) < .001*
Cross-Training Per Week (N) 3.17 ± 2.09 3.09 ± 1.97 0.08 (0.07) 0.25
Weekly Mileage (mi) 24.63 ± 18.36 25.49 ± 18.38 0.87 (0.33) .01*
Pace (min/mi) 9:48 ± 1:51 9:24 ± 1:54 -0:24 (0:29) 0.35
Running Motives (N) 3.05 ± 1.73 2.65 ± 1.53 -0.41 (0.04) < .001*
Typical Running 1.71 ± 0.92 1.82 ± 1.04 0.11 (0.03) < .001*
Time Blocks (N)

Abbreviations: CI, confidence interval; N, number; mi, mile; min, minute.

*Significant at p < .05.

Fig 3.

Fig 3

(A) Difference in number of running motives and (B) running times of day during the pandemic. (C) Motives for running and (D) running times per day before and during the pandemic by percentage responses. (E) Running locations before and during the pandemic by percentage responses. Differences in numbers of (A) running motives and (B) running times of day represented in the histograms, with increases in outcomes depicted in blue, and decreases depicted in red, and increased number of occurrences represented with darker color shades. Percentage responses for (C) running motives, (D) running times per day, and (E) running locations before and during the pandemic are depicted within the stacked bar plots.

When examining shifts in running motives during the pandemic, there was a decrease in responses for competition/races and socialization as driving factors for running participation, while there were more responses that participants were motivated to run to occupy free time (Fig 3C). Less runners reported exercising early in the morning (5-7AM) and the early evening (5-7pm), but increased activity mid-day (11AM-1PM) during the pandemic compared to prior running behaviors (Fig 3D). Finally, respondents reported running substantially more outdoors than indoors during the pandemic than before (Fig 3E).

The results of the regression analyses assessing the influence of demographic factors on running behaviors can be found in Table 2. The only significant finding for sex in the model was that males were less likely to decrease (Odds Ratio with 95% Confidence Interval [OR]: 0.66 [0.47,0.93) or increase (OR: 0.47 [0.34, 0.64]) their weekly mileage compared to females. Otherwise, the key factors influencing running behavior changes were related to running experience and age. Notably, runners with 0–3 years of running experience were significantly less likely to decrease their number of runs per week than maintain their running volume compared to runners with 4–10 and 11–15 years of experience (OR0-3 vs. 4–10: 0.60 [0.42, 0.88]; OR0-3 vs. 11–15: 0.62 [0.38,0.99]), and were less likely to increase their number of sustained runs per week than maintain running habits when compared to runners with 4–10 and 11–15 years of experience (OR0-3 vs. 4–10: 0.66 [0.45, 0.97]; OR0-3 vs. 11–15: 0.49 [0.29,0.82]). However, runners with 0–3 years of experience also were more likely to decrease their overall weekly mileage compared to runners with 4–10 years of experience (OR: 1.80 [1.17, 2.76]). Runners with 0–3 years of experience were also significantly less likely to decrease their number of reported workouts per week when compared to runners with 11–15 and 16–20+ years of experience (OR0-3 vs. 11–15: 0.43 [0.22, 0.83]; OR0-3 vs. 11–15: 0.39 [0.20, 0.75]), and less likely to increase their number of workouts compared to 16–20+ years of experience during the pandemic (OR: 0.25 [0.08, 0.73]). Finally, runners with 0–3 years of experience were less likely to increase their running motives compared to all other runner groups (OR0-3 vs. 4–10: 0.35 [0.20, 0.60]; OR0-3 vs. 11–15: 0.20 [0.08, 0.48]; OR0-3 vs. 11–15: 0.23 [0.10, 0.53]).

Table 2. Logistic regression outcomes assessing the influence of demographic factors on running behavior changes during the pandemic.

Total N Runs Odds Ratio Sustained Runs Odds Ratio Workouts Odds Ratio Motives Odds Ratio Times of Day Odds Ratio Mileage Odds Ratio
(95% CI) (95% CI) (95% CI) (95% CI) (95% CI) (95% CI)
Predictor Comparison ↓ vs. No Change ↑ vs. No Change ↓ vs. No Change ↑ vs. No Change ↓ vs. No Change ↑ vs. No Change ↓ vs. No Change ↑ vs. No Change ↓ vs. No Change ↑ vs. No Change ↓ vs. No Change ↑ vs. No Change
Age 18–25 vs. 1.2 0.81 0.98 (0.55, 1.72) 0.98 (0.64, 1.50) 0.53 (0.32, 0.86) * 1.02 (0.35, 2.96) 1.12 (0.72, 1.73) 1.06 (0.59, 1.89) 0.30 (0.12, 0.73) * 0.74 (0.35, 1.54) 0.60 (0.38, 0.93) * 0.79 (0.51, 1.21)
26–35 (0.78, 1.84) (0.52, 1.27)
18–25 vs. 0.88 0.61 0.73 (0.39, 1.36) 0.82 (0.52, 1.29) 0.60 (0.36, 1.01) 1.93 (0.70, 5.33) 1.02 (0.64, 1.62) 0.60 (0.29, 1.21) 0.35 (0.14, 0.89) * 0.92 (0.44, 1.95) 0.57 (0.35, 0.92) * 0.73 (0.46, 1.17)
36–45 (0.56, 1.41) (0.37, 1.01)
18–25 vs. 1.02 1.44 0.58 (0.27, 1.25) 0.68 (0.40, 1.18) 0.56 (0.28, 1.12) 1.91 (0.55, 6.67) 1.02 (0.60, 1.72) 0.47 (0.18, 1.22) 0.38 (0.13, 1.10) 0.48 (0.18, 1.23) 0.40 (0.22, 0.71) * 0.70 (0.42, 1.18)
46–55 (0.60, 1.73) (1.23, 1.86) *
18–25 vs. 56+ 0.77 (0.39, 1.54) 1.15 0.96 (0.42, 2.18) 0.49 (0.24, 1.01) 0.53 (0.22, 1.27) 3.47 (0.92, 13.13) 1.11 (0.60, 2.07) 0.48 (0.13, 1.78) 0.33 (0.08, 1.35) 0.41 (0.13, 1.30) 0.50 (0.26, 0.97) * 0.43 (0.22, 0.84)
(0.60, 2.22)
Sex Male vs. Female 1.04 (0.75, 1.43) 1.19 0.75 (0.49, 1.14) 1.06 (0.76, 1.46) 1.30 (0.87, 1.96) 1.84 (0.83, 4.09) 1.35 (0.97, 1.87) 1.22 (0.72, 2.06) 1.70 (0.81, 3.58) 1.31 (0.77, 2.23) 0.66 (0.47, 0.93) * 0.47 (0.34, 0.64) *
(0.82, 1.72)
Years Running Experience 0–3 vs. 0.6 0.94 0.85 (0.51, 1.43) 0.66 (0.45, 0.97) * 0.90 (0.57, 1.41) 0.42 (0.18, 1.00) 1.28 (0.86, 1.92) 0.35 (0.20, 0.60) * 1.35 (0.59, 3.11) 1.03 (0.50, 2.14) 1.80 (1.17, 2.76) * 0.90 (0.61, 1.32)
10-Apr (0.42, 0.88) * (0.62, 1.41)
0–3 vs. 0.62 (0.38, 0.99) * 0.64 0.59 (0.29, 1.17) 0.49 (0.29, 0.82) * 0.43 (0.22, 0.83) * 0.42 (0.15, 1.21) 1.04 (0.63, 1.72) 0.20 (0.08, 0.48) * 1.39 (0.47, 4.17) 2.55 (1.18, 5.51) * 1.43 (0.82, 2.49) 1.27 (0.79, 2.02)
15-Nov (0.36, 1.14)
0–3 vs. 0.79 0.68 0.73 (0.38, 1.40) 0.84 (0.53, 1.33) 0.39 (0.20, 0.75) * 0.25 (0.08, 0.73) * 1.14 (0.71, 1.83) 0.23 (0.10, 0.53) * 1.72 (0.57, 5.17) 2.70 (1.23, 5.89) * 1.56 (0.91, 2.65) 1.10 (0.70, 1.74)
16–20+ (0.50, 1.23) (0.39, 1.19)
Location US EC vs. US Mw 0.79 (0.56, 1.11) 1.00 (0.69, 1.44) 1.51 (0.74, 1.78) 1.05 (0.75, 1.46) 0.94 (0.64, 1.39) 0.61 (0.28, 1.35) 1.28 (0.93, 1.76) 1.17 (0.70, 1.95) 0.89 (0.44, 1.82) 0.73 (0.42, 1.29) 1.03 (0.73, 1.47) 1.12 (0.81, 1.55)
US EC vs. US WC 1.73 (0.87, 3.46) 1.34 0.50 (0.11, 2.17) 1.70 (0.84, 3.43) 0.48 (0.14, 1.64) 1.35 (0.30, 6.19) 0.94 (0.42, 2.10) 1.49 (0.49, 4.59) 1.82 (0.51, 6.45) 0.61 (0.14, 2.62) 1.16 (0.52, 2.59) 1.21 (0.58, 2.50)
(0.56, 3.19)

Table presenting the results of the logistic regression model. The odds ratios presented are the results when comparing the first listed group to the second, such that if the odds ratio is less than one that the first group listed was less likely to change behaviors, and conversely if the odds ratio is greater than one the first group listed was more likely to change. The odds ratio reference was no change in running behavior, and both likelihoods to increase or decrease running behaviors were assessed and presented in the table columns. Abbreviations: N, number; CI, confidence interval; US, United States; EC, East Coast; WC, West Coast.

*Significant at p < .05.

When assessing the effects of age in the model, younger runners ages 18–25 were more likely to increase number of runs per week compared to runners ages 46–55 (OR: 1.44 [1.23, 1.86]). Additionally, runners ages 18–25 were significantly less likely to decrease their overall weekly mileage compared to older runner groups during the pandemic (OR18-25 vs. 26–35: 0.60 [0.38, 0.93]; OR18-25 vs. 36–45: 0.57 [0.35, 0.92]; OR18-25 vs. 46–55: 0.40 [0.22, 0.71]; OR18-25 vs. 56+: 0.50 [0.26, 0.97]). Finally, runners ages 18–25 were significantly less likely to decrease their number of workouts (OR18-25 vs. 26–35: 0.53 [0.32, 0.86]), and training times of day during the week (OR18-25 vs. 26–35: 0.30 [0.12, 0.73]; OR18-25 vs. 36–45: 0.35 [0.14, 0.89]) during the pandemic.

Running-related injuries

410 participants (35.7%) reported a total of 634 injuries in the year prior to the pandemic (Average days off of running: 42±48; Average days of modified running: 60±63), while 144 (12.6%) reported a total of 219 injuries during the 3-month social isolation period of the pandemic (Average days off of running: 10±12; Average days of modified running: 18±34). Of the reported RRI’s incurred prior to the pandemic, 63 participants reported injury during the pandemic (15.4%). Injuries by type and body part can be found in Table 3. While raw outcomes reflected a higher number of injuries prior to the pandemic, the 3-month adjusted injury risk ratio demonstrated that there was 1.40 times the injury risk (Confidence Interval: 1.18,1.61) during the pandemic as compared to prior to the social isolation period. The logistic regression model only explained 1.66% of the variance, and none of the demographic factors included in the model were significant predictors of RRI during the pandemic when covarying for previous injury.

Table 3. Injuries reported before and during the pandemic by injury type and body part.

Sprain / Ligamentous Strain / Musculotendinous Fracture / Stress Fracture / Bony Other Total Injuries by Location
(N reported) (N reported) (N reported) (N reported)
Before During Before During Before During Before During Before During
Toe 6 0 2 2 7 1 2 1 17 (2.68%) 4
-2.44%
Foot 33 11 57 10 14 4 8 6 112 (17.67%) 31 (18.90%)
Ankle 44 9 38 11 7 0 3 1 92 (14.51%) 21 (12.80%)
Lower Leg 4 2 59 14 20 2 22 8 105 (16.56%) 26 (15.85%)
Knee 25 4 51 22 0 0 22 15 98 (15.46%) 41
-25%
Thigh 0 0 24 5 1 0 1 0 26 (4.10%) 5
-3.05%
Hamstring 4 1 41 5 0 0 3 2 48 (7.57%) 8
-4.88%
Hip 2 0 47 7 6 1 16 10 71 (11.20%) 18 (10.98%)
Groin 1 0 7 4 1 0 1 0 10 (1.58%) 4
-2.43%
Abdominals 1 0 1 0 2 0 1 0 5 0
-0.79% 0%
Lower Back 2 0 33 3 2 0 13 3 50 (7.89%) 6
-3.66%

Abbreviations: N, number; Before, the year prior to the pandemic; During, the period of social isolation during the pandemic.

Response themes and additional outcomes

Of the original 1147 respondent sample, 638 participants provided short responses. Based on the results of the open coding assessment, several notable key words were identified that aided in thematic response labeling (S1 Table). The major emergent themes were competition changes (610 instances), motivation (192 instances), well-being (69 instances), situational factors (181 instances), social support (121 instances), and resiliency (181 instances). Under the competition changes theme, two sub-categories emerged: race cancellations without alternative participation methods, and race postponements/virtual race alternatives. Under motivation, the two underlying categories identified were decreased motivation to continue running, and no effect on training goals due to established training habits. Under the well-being theme, the two emergent categories were increases in training to improve health, and alterations in training due to fear of injury occurrence. All other themes had a singular underlying category in responses, and response examples by theme categories can be found in Table 4.

Table 4. Short response examples by response themes.

Response Theme Category Sample Responses
Competition Changes (610 Instances) Race cancellations or uncertainty without alternative participation methods (381 Instances) “I was planning on running a race in March 2020 which got cancelled. I was also planning on potentially running a race in fall 2020, but I haven’t signed up nor do I plan to at the moment because of COVID-19.”
“I had been training for a half which was ultimately postponed. No date has been announced yet so I can’t set up a new schedule…”
“I had been training for 5 months and the race was canceled. I miss the spring 5K races. I’m concerned about the fall 5K races.”
“I am concerned about the upcoming cross country and track seasons. Even if season happens, we will be severely restricted due to huge budget cuts. I am concerned I will have to pay to be a student athlete.”
“I am supposed to start training in June for a marathon to be held in October. I am hesitant to start this high intensity training with the possibility that the race may be cancelled.”
Race postponements/Virtual race alternatives (229 Instances) “Can’t race in planned events but registered for 2 virtual [races]”
“Have done more virtual races.”
“I’m participating in Virtual Events just-in-case my fall running events get canceled.”
“The pandemic has canceled/post-poned a lot of my races, so I’ve opted to do some virtually (which is fine, but NOT the same)…”
Motivation (192 Instances) Decreased motivation to continue running due to lack of extrinsic motivators (175 Instances) “Hard to set goals with no races”
“…I have fallen back to running 3–4 miles at most because I’ve lost the motivation to run without an upcoming race (since all have been canceled) and without friends to run with.”
“The interruption to my training has been mental. I’ve struggled to find motivation to maintain my training, and I’m generally mentally healthy. This has just been different, and it has affected me more than I ever would have expected.”
“I’ve mainly lost my motivation without having the social or competition aspect of running.”
No effect on training goals due to established training methods (17 Instances) “My training has worked for me for years and I won’t change it because of this one virus.”
“I still have goals. I still have things I’m working towards. A break from racing doesn’t change that.”
“honestly hasn’t changed running for me at all…[COVID] won’t stop my love for running and training in general”
Well-Being (69 Instances) Running as a means to improve health and wellness (56 Instances) “I’ve become much more committed to regular runs in order to improve cardiovascular health, in order to improve my chances of recovery if I contact COVID-19”
“Just running for fun and fitness and increasing stretching and weight training.”
“As someone who has health issues the year prior I saw this as an opportunity to regain lost fitness and still set goals without races…”
Altered training habits due to fear and/or occurrence of injury and illness (13 Instances) “The changes to my training are mostly injury related (still recovering from plantar fasciitis)…”
“I am a little concerned about increased risk of injury due to more volume on roads.”
“The biggest change I made was shortening my long run each week. I did this in order to avoid any overuse injury during the pandemic.”
Situational Factors (181 Instances) Home or locally-imposed restrictions changing running training habits “Being home 24/7 and having added responsibilities has made taking care of myself more difficult”
“At the start in March I was running 4–6 times a week. Then our county required face masks and I run on a walking path pushing a stroller. Due to that I stopped running.”
“Due to schedule changes necessitated by the quarantine, I have been forces to conduct interval training on an assault bike in lieu of running.”
“I am a resistance trainer at heart, but out of lack of options have had to increase my running dosage and frequency as all the gyms are closed.”
“…The XXXX Trail is too busy to run responsibly. I now run almost exclusively on the road/sidewalk, which was never my preference…”
“I have more time to train because I no longer need to commute to work (40 min. each way)—I am currently working from home.”
“I’m a terrible runner and always wanted to start, so COVID-19 has given me a chance to gradually build up my ability due to more free time and good weather.”
“I changed from my normal scenic trail to a less populated area (sidewalks in a neighborhood instead of a running path along a river)”
“With two teenage girls distance learning and my normal work routine disrupted by educational closures, mileage went down dramatically.”
Social Support (121 Instances) Lack of social groups creating training changes “I miss racing and having a goal race. I also miss big group runs.”
“I miss having a tangible goal, and I REALLY miss my running groups and friends. Tougher to stay motivated when you can’t run with other people.”
“It is much harder to do speed work alone. I miss chasing my friends at the track and the motivation we provide each other.”
“The lack of running partners makes long runs very difficult”
Resiliency (181 Instances) Began/Maintained running with positive outlook “Just working on getting better and enjoying the process”
“I am running more now than before!”
“I did not run regularly before COVID-19. I now run several times a week and set goals as well, goals that I have been meeting.”
“I have been much more consistent with my running during this pandemic.”
“I’ve taken time to stop marathon/ half marathon training focus and instead work on flat speed (mile to 5k training) and increased cross training knowing that both of these will benefit me in the long run to stay healthy and get faster in a time of races. This will translate to faster halves and fulls in the future. Plus it’s fun to do something a little different! I think this change also helps mentally to fight any burnout.”
“I have been able to get in quality training and actually have been able to run more mileage and harder workouts.”

Sample responses provided from the survey under response theme categories.

The majority of participants (57.82%) perceived that their running training had increased ranging from a little to a great deal, while the remaining participants felt that their training had not changed (12.32%), or decreased to varying degrees (29.86%). About 20% of respondents reported feeling somewhat or very concerned about the effect the pandemic will have on their running training, and about 40% of respondents were somewhat or very concerned about their running goals.

Discussion

The COVID-19 pandemic imposed a unique stress on daily functioning worldwide, and the results of this survey indicate that there has been a reactionary response in the running community. The primary hypotheses were mainly supported in that the runners sampled in this survey reported increased running volumes with decreased intensity, coinciding with increased injury risk and alterations in running training motives. These findings may be of use to coaches when developing training programs and sports medicine clinicians in preparing for patient loads as social isolation restrictions become lifted.

Running behaviors and injury risk

Overall, runners increased their number of runs per week, weekly mileage, and number of times of day they opted to run. We postulated that this response would be seen given the accessibility of running training and the physical and mental health benefits associated with this form of cardiovascular activity [3]. This response was perpetuated in the short answer health response themes, as individuals cited beginning or maintaining running to combat weight gain, maintain fitness, and protect against COVID-19 respiratory health complications [14]. Running motives additionally shifted away from social and competitive aspects of the activity, and towards stress relief, occupying free time, and fitness. We believe these underlying factors, along with access to facilities such as gyms and tracks reported in short answer responses, further coincide with the noted decrements in training intensity and fewer overall number motives for continuing training.

Tendency towards increased running volume but with decreased running intensity is critical information for coaches and sports medicine clinicians to consider during the transition back to normal training schedules. Sudden increases in running training intensity have been associated with acute lower extremity injuries, such as Achilles tendinopathies and gastrocnemius strains [13]. Our findings suggest that runners decreased their running intensities which may have reduced some acute injury outcomes in the pandemic timeframe. However, there is a potential that sudden re-introduction of high intensity training would result in acute injury risk. Therefore, an emphasis on gradual re-introduction to workouts and higher intensity training such as intervals and speed workouts should be considered during return to competitive running training given the noted decline in training intensity during social isolation. Knowledge of these running behavior changes will help coaches and sports scientists to create graded return to activity protocols bearing in mind progressive, cyclical periodization tactics to mitigate acute injury in the running community [15]. Although many runners reported an eagerness to return to racing and high intensity training in their short answer responses, runners should be informed of the risks acute training changes may imposed on their physical health.

In a similar vein, overuse injuries are frequently cited to occur with sudden training changes [12, 13, 16], akin to the documented increase in total number of runs, mileage, and sustained runs during the pandemic. Prevalent lower extremity overuse injuries are linked with training errors, such as running primarily on asphalt and high weekly running exposure [12, 13, 17, 18]. Not only was the injury risk higher among participants during the pandemic, but the majority of reported injuries were categorized as two of the most prevalent overuse RRI’s: patellofemoral pain and medial tibial stress syndrome housed within the “other” injury response categories (Table 3). Further, locally-imposed restrictions resulted in a 23% increase in exclusive outdoor running training among participants (Fig 3E). Although these factors were not significant predictors for sustaining RRI, these factors should still be clinically considered, particularly in the upcoming year as running exposures continue during the gradual return to routine functioning.

Continued health monitoring among the running community is a necessary next step to determine how RRI epidemiology will shift in the upcoming years. As a note of caution, we did not explicitly ask participants about overuse and chronic injury categorizations, and instead kept the injury definition intentionally broad with greater details elucidated in the injury types by body part chart. Further, as injury outcomes were assessed for the year leading up to the pandemic, there is a potential for recall bias in the reported outcomes. These concepts should be considered when interpreting the injury data; however, we believe the reported information provides valuable insights into injury outcomes during this unique time. Clinicians treating RRI’s should be aware of the noted increase in time-adjusted overuse injury outcomes determined from this study sample to adequately prepare for patient volumes when clinics begin to re-open.

It was a surprising finding that cross-training activities did not significantly differ during the pandemic; we anticipated cross-training to decrease due to limited access to gyms and other training facilities. However, short-responses reflected that individuals opted to perform lighter intensity cross-training activities due to lack of access to heavier weights and machinery that were not adequately captured in this survey response. Key stakeholders should assess athletes’ abilities to perform cross-training activities during the pandemic period, and the intensity of the exercises before returning to strenuous exercise.

Personal and geographic factors

The largest demographic factor influencing running training was found to be age; younger runners were significantly less likely to decrease their mileage compared to all other age groups. We believe this is attributed to personal demands, particularly as runners in older age categories reported increased work and home-schooling demands. It was somewhat of a surprising finding that there was not a significant interaction between age and sex on running behaviors, nor between age and experience on running behaviors. We anticipated that female runners ages 36–45 would report lesser running volume due to increased familial demands, and that younger runners with more experience would be more resilient to social isolation changes in running behaviors due to less home-based demands and more routine training. However, experienced runners were less likely to decrease their weekly training volume regardless of age which we believe is reflective of established training plans, and females were more likely to change weekly mileage than males.

Unfortunately given the convenience sampling methods, there were not enough international responses to determine if isolation measures disproportionally influenced runners’ behavioral responses by geographical location. An added layer of difficulty to interpretation of responses is that many social isolation decision measures were made at local regional levels and not on full state or country levels. Based on our sampling approach, we were unable to determine if there was a differential response based upon exact region, especially when considering differences such as rural versus urban habitancy which may have influenced the results. We found that there was not a significant influence of geographical region on running behaviors, although individuals did cite local closures and requirements of wearing masks during activity that hindered their running training.

Implications for telemedicine

The results of this survey highlight several important opportunities for coaches and sports medicine clinicians to leverage technology that runners are already using to improve runners’ motivations, aid in goal-setting, and mitigate injury risk during periods of remote interactions. As ~90% of runners reported utilizing technology to keep track of their runs, there is already a wealth of information available on habitual training behaviors such that remote interventions can be tailored and facilitated to meet runners’ needs during this time.

Runners consistently reported decreases in social support as barriers to their running training during the pandemic, and short-responses emphasized missing community and team encouragement to maintain running habits. Furthermore, the majority of runners reported concerns about their overall running goals during the social isolation period. While these were the main themes throughout runners’ responses, there was a subgroup of runners that demonstrated resilience and alternative means of encouragement by completing virtual races and remote running clubs. Clinicians and coaches can utilize this information to help increase adherence to running and reduce the barriers to training in future periods of remote contact. Although the pandemic is distinct in that direct contact is not possible, there are still situations in which coaches and clinicians may not be able to directly come in contact with runners (i.e. off-season training, geographical location differences, etc.). Key stakeholders may consider performing motivational interviewing with runners to help elucidate individuals’ needs for extrinsic motivating factors contributing to their own training. This would help introduce the opportunity connect runners with one another using virtual tracking to foster social support, and connect with virtual race opportunities to prevent losing competitive motivation [19]. In terms of maintaining runners’ goals or creating tangible running goals, technology-based coaching has been found to increase adherence to workout schedules and more regular training that would help prevent sudden training changes as seen in this study [20].

The injury outcomes from this survey highlight the importance of incorporating telehealth initiatives to inform runners of the risks of training volume and overuse injuries as preventative measures. While direct face-to-face patient-clinician interactions are being gradually re-introduced for non-emergent medical conditions, clinicians should become more adept to leveraging technology to reach their patients. The findings from this survey support sharing general training information to runners to mitigate spikes in injury epidemiology over the upcoming months to years, with a particular emphasis on training dosage. These plans would be particularly beneficial for runners with some limited running experience (4–10 years), as this runner group was found to be more susceptible to training changes. These plans may also be helpful for novice runners who reported a decline in weekly running mileage during the pandemic; this group may need guidance during return to running activity as restrictions are lifted due to less knowledge on safe training increases [21]. Clinicians may use patients’ data to objectively inform remote interventions to promote health and decrease injury risk. Overall, the survey outcomes support telemedicine initiatives in the upcoming months to years to conduct remote monitoring and interventional plans for runners in training and recovery contexts.

Limitations

This was a cross-sectional survey of running behaviors, and therefore there is a potential for recall bias in responses pertaining to previous training habits and injury history. We attempted to account for this issue by asking respondents about the year prior to the pandemic, and not a longer timeframe. Given that social isolation measures occurred at different timepoints globally, we asked participants to respond in the timeframe that they experienced these protective prevention measures. For this reason, we could not calculate true injury risk due to differences in assessment timeframes. However, we decided to perform an injury risk adjustment given the social isolation procedures were in effect for the majority of respondents in the United States for three months (March-May). We believe the equivocal time period comparison most appropriately modeled the observed effects. Future work exploring injury risk during the return to routine functioning on a similar timeframe to the year prior to social isolation to get a true estimate of RRI following the pandemic is warranted. We were unable to assess re-injuries or chronic injuries explicitly in this study which may have influenced the RRI findings, however we accounted for previous injury as a covariate in regression analyses. Running goals, for example, recreational versus elite participation, is likely to influence motivation. While we did assess runners’ motives for running, we did not obtain runners’ primary running level and could not perform sub-group analyses to this point. Finally, the survey was only distributed in English, and the majority of respondents were from the United States, and primarily on the east coast. The results may have been influenced more heavily by pandemic response measures in these regions, and therefore the results should be interpreted as descriptive outcomes for the included sample and may not reflect the global running community.

Conclusions

The COVID-19 pandemic influenced runners’ behaviors and resulted in increased training volume with decreased training intensity. Runners’ motivations for running overall declined, and shifted from competition and socialization towards fitness, stress relief, and occupying time. Running-related injury risk was overall higher during the pandemic for lower extremity overuse injuries compared to the year prior. These findings highlight changes in running training patterns, motivations, and injury risk in adult distance runners and should be considered by coaches and sports medicine clinicians as social isolation measures are relaxed.

Supporting information

S1 Fig. (A) Percentage of respondents by state within the United States, (B) percentage of respondents by country, (C) responses by state: change in number of sustained runs, (D) responses by country: change in number of sustained runs, (E) responses by state: change in number of running workouts, (F) responses by country: change in number of running workouts.

Abbreviations: Avg, Average; Diff, Difference; N, number.

(TIF)

S1 File. Running behaviors before and during the COVID-19 pandemic survey.

List of questions and response options included in the survey. Question logic was used to skip irrelevant questions and displayed within the document.

(DOCX)

S1 Table. Open coding short response items.

The words or phrases that most frequently occurred in short responses were grouped into like categories and displayed in the table, along with number of instances noted throughout the short responses.

(DOCX)

Acknowledgments

We would like to thank members of the Exercise and Sport Injury Laboratory for their feedback on this survey, and Luzita Vela for her guidance in qualitative analyses.

Data Availability

Due to ethical restrictions, the data underlying this study may not be shared publicly. Data are available from the University of Virginia Ethics Committee (contact via Jeffrey Monroe, mjm6ny@virginia.edu) for researchers who meet the criteria for access to confidential data.

Funding Statement

The authors received no specific funding for this work.

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Decision Letter 0

Maria Francesca Piacentini

15 Jul 2020

PONE-D-20-18783

Running behaviors, motivations, and injury risk during the COVID-19 pandemic: A survey of 1147 international runners

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Reviewer #2: Yes

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4. Is the manuscript presented in an intelligible fashion and written in standard English?

PLOS ONE does not copyedit accepted manuscripts, so the language in submitted articles must be clear, correct, and unambiguous. Any typographical or grammatical errors should be corrected at revision, so please note any specific errors here.

Reviewer #1: Yes

Reviewer #2: Yes

**********

5. Review Comments to the Author

Please use the space provided to explain your answers to the questions above. You may also include additional comments for the author, including concerns about dual publication, research ethics, or publication ethics. (Please upload your review as an attachment if it exceeds 20,000 characters)

Reviewer #1: Thank you for your interesting and timely paper. You have obviously put a great deal of hard work, over a short period of time, into this study, for which I congratulate you. I should like to make a few suggestions, however, as to how (I feel) you might be able to improve the usefulness to others, as well as the and citability, of your work:-

1. Did you define injury in the survey? If so, please include the definition in the paper.

2. Did you also differentiate between overuse and traumatic injury in the survey (or only between different injury types as per Table 3)? If you did not your report of the strength of the links between the injury data and the training modification related data could be misleading. Please clarify what you did.

3. Was the survey in English only (seeing as this potentially impact on the validity of the answers to it from some countries) ? I presume so – if this was the case did you in fact assess the extent to which your respondents were native English speakers? I supposed from Fig 1A that they were but then Fig 1ab and line 209-213 seem to show that they may not all have been so. It would have helped me assess your paper if I could have seen the survey- it sounds from what you wrote in Line 94 that you intended to include it in an appendix but there was no appendix in what I received

4. Did you assess how long the subjects has been in lock down and the extent to that lockdown in the survey? You seem to assume that it had been for 3 months but you collected the data over a period of 1 month so the lockdown could have been over up to 4 in some cases and this would affect your calculations

5. Why did you ask for training data for the previous year rather than for say the three months prior to lockdown (for which recall would have been better) or regarding “what you would normally do at this period of your competitive/training year”? You report training data to 2 decimal places but presumably (and from my experience and data) the number and volume of sessions changes from one type of macrocycle to the next (e.g. between pre-competition and competition or endurance base and pre-competition periods). The extent to which it does so may well be more than the pre-during pandemic changes that you report, and render your method of assessing pandemic induced change (ie subtract one from the other) less meaningful than it might have been.

6. I realise that you have loads of data but the way you present the data in the figures makes it difficult to see exactly what they are. Fig 3AB for example is hard to understand- perhaps you might consider whether there is a better way of showing these data?

7. Your supplemental data seem to show that you used varying numbers of respondents for the statistical analysis- as the number of responses to each question differed at different points of the survey? Was this the case? In line 135 you state that only complete data were used

8. Some of the legends are incomplete e.g. for Table 2 you mention EC vs WC but I could not see the explanation of the abbreviation, in Table 1 you do not specific units for mileage

9. From your Table 3 and using the reasoning that you proposed/used elsewhere (divide the values for a year by 4, if I understood that correctly) the injury n was higher for both sprains and strains before the pandemic than it was during (30 vs. 27 and 81.75 vs. 80), apart from in the case of fractures (14.5 vs 8). This isn’t discussed. It contradicts your conclusion in the abstract. Unless you did not in fact analyse complete data sets as noted in the paper? (or I have misunderstood in which please accept my apologies for this point).

10. Some of your discussion goes over stuff that you have not included in the results. I would revisit both sections accordingly.

Thank you in advance for the clarifications.

Best wishes

Reviewer #2: This manuscript investigates the effect of COVID-19 on running behaviors and motivation, using an international survey.

I found the paper to be generally well written. The manuscript addresses a very relevant and important topic. Overal, the methods section is detailed, although some important remarks need to be considered to strengthen the paper. The results are clear and comprehensive. However, some concerns relating to the statistical analysis and interpretations of the results are present, which should be revised before considering publication.

2.1. General comments:

1. The main concern relates to the representativeness of the survey. A convenience sample was used in the survey, without prior calculation of the number of participants needed for the survey to be representative for the targeted population (i.e. international runners). The manuscript should be revised while integrating this reflection, both in the methods, results and discussion. This prevents the interested reader from misinterpreting the results and providing a sound answer to the question: "Are these results able to represent the behavior of the complete population (if yes, include total error of the survey), or are these results to be interpreted as descriptive for the included sample."

2. Data-analysis: the authors select the paired t-test, without description whether or not the required conditions were fulfilled. Also, please provide more detail in the survey analysis (i.e. depending on data level, processing of open answers)

3. Data-analysis: the authors select to adjust injury data at group level and not at individual level. Did the survey not allow to calculate or estimate individual exposure and injury risk? Please provide additional rationale for this extrapolation at group level, because this influences greatly the results.

Additional comments:

- Injury definition of running related injuries: please elaborate on how recall bias influences injury data throughout the survey. Overuse injuries (running related injuries) are susceptible for this kind of bias and are dependent of the selected injury definition.

- The survey aims to include international runners, but the COVID-quarantine differs in each country / region. This conflicts with earlier comment on representativeness. Consider sub-group analysis for those regions that allow for a more representative analysis?

- The survey included all levels of runners, but the level (competition or recreational) can be of great influence to motivation. Group analysis might conceal sub-group differences? Did the authors consider sub-group analysis for motivation?

- How reliable are the exposure, injury and training data? Can the authors provide some additional insights in this matter?

- Results: what about the re-injuries or chronic injuries? How were these processed during data-analysis?

- Discussion: The decreased intensity seems to contradict the increased injury risk? This is to be interpreted in the broader context of training volume; including both training intensity and frequency, so please discus this interaction more extensively.

- Discussion: see above, please reflect on the representativeness and/or margin of error of the survey, relating to either the entire population or the included sample.

**********

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Reviewer #1: No

Reviewer #2: No

[NOTE: If reviewer comments were submitted as an attachment file, they will be attached to this email and accessible via the submission site. Please log into your account, locate the manuscript record, and check for the action link "View Attachments". If this link does not appear, there are no attachment files.]

While revising your submission, please upload your figure files to the Preflight Analysis and Conversion Engine (PACE) digital diagnostic tool, https://pacev2.apexcovantage.com/. PACE helps ensure that figures meet PLOS requirements. To use PACE, you must first register as a user. Registration is free. Then, login and navigate to the UPLOAD tab, where you will find detailed instructions on how to use the tool. If you encounter any issues or have any questions when using PACE, please email PLOS at figures@plos.org. Please note that Supporting Information files do not need this step.

PLoS One. 2021 Feb 12;16(2):e0246300. doi: 10.1371/journal.pone.0246300.r002

Author response to Decision Letter 0


4 Aug 2020

Responses to Editor

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Response: We have made the appropriate stylistic adjustments, and highlighted the changes throughout the revised manuscript.

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Response: There is an ethical restriction to sharing the data publicly, as the IRB-approved study consent form had a required section that indicated to participants that their data will be protected, will not be shared, and will be destroyed upon study completion. We do not have contact information for all participants since this was an anonymous online survey and cannot follow-up asking if they would be willing to share their data. We have been in contact with the IRB, and they informed us that subsequently, the data cannot be shared publicly. Instead, we have attached the output from the statistical analyses for increased data transparency.

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Response: We have included a title page now within the main document.

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Response: We contacted Mapbox, and received the following information:

Thanks for writing in. While we do not sign paperwork for special agreements, our Terms of Service serves as the contract for use of your Mapbox account. As long as your maps follow our attribution and watermark requirements, you can use them in your publication.

While we could not obtain the signed copyright form, we adjusted the images according to their requirements and should be suitable for publication.

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Response: We have included the tables now in the main manuscript and removed the individual files.

6. Please upload a copy of Supplementary Table which you refer to in your text on page 14.

Response: We apologize the table did not successfully upload in the original submission, we have re-formatted the document and included this now in the revision.

7. Please include captions for your Supporting Information files at the end of your manuscript, and update any in-text citations to match accordingly. Please see our Supporting Information guidelines for more information: http://journals.plos.org/plosone/s/supporting-information

Response: This information is now included at the end of the manuscript.

Responses to Reviewer 1

Reviewer #1: Thank you for your interesting and timely paper. You have obviously put a great deal of hard work, over a short period of time, into this study, for which I congratulate you. I should like to make a few suggestions, however, as to how (I feel) you might be able to improve the usefulness to others, as well as the and citability, of your work:-

Response: Thank you for taking the time to review our manuscript, we appreciate the insights intended to strengthen the interpretation of the survey findings. We have addressed the specific comments and questions below to the best of our ability.

1. Did you define injury in the survey? If so, please include the definition in the paper.

Response: We kept the injury inclusion for this study broad, and aimed to capture more specific injury information about the injury types by body part in the table included in the survey. We apologize, the PDF of the survey did not successfully upload in the initial submission. We re-formatted this supplemental material and uploaded the details in this revision. We have address this in the text on lines 116-117.

2. Did you also differentiate between overuse and traumatic injury in the survey (or only between different injury types as per Table 3)? If you did not your report of the strength of the links between the injury data and the training modification related data could be misleading. Please clarify what you did.

Response: We did not specifically differentiate between overuse and traumatic injuries, however we did collection information on the duration that the injury influenced their running training, as well as time off from injury. Since we also collected information on injury types, we believe that we still have collected relevant data that provides insight into overuse versus acute injuries. We included this point on lines 369-375, and 460-462.

3. Was the survey in English only (seeing as this potentially impact on the validity of the answers to it from some countries) ? I presume so – if this was the case did you in fact assess the extent to which your respondents were native English speakers? I supposed from Fig 1A that they were but then Fig 1ab and line 209-213 seem to show that they may not all have been so. It would have helped me assess your paper if I could have seen the survey- it sounds from what you wrote in Line 94 that you intended to include it in an appendix but there was no appendix in what I received

Response: The survey was only provided in English, we have included a statement about this now in the methods on line 84, and acknowledged this as a limitation on lines 465-466. We apologize that the survey did not successfully upload in the initial submission, this is available now as a supplemental document.

4. Did you assess how long the subjects has been in lock down and the extent to that lockdown in the survey? You seem to assume that it had been for 3 months but you collected the data over a period of 1 month so the lockdown could have been over up to 4 in some cases and this would affect your calculations

Response: We did not explicitly assess the length/extent of lock-down in this survey. Unfortunately, this information is extremely specific to individuals and to the region in which they live. We decided to utilize the average amount of time the quarantine was in effect. We included this information on lines 452-458 as a limitation.

5. Why did you ask for training data for the previous year rather than for say the three months prior to lockdown (for which recall would have been better) or regarding “what you would normally do at this period of your competitive/training year”? You report training data to 2 decimal places but presumably (and from my experience and data) the number and volume of sessions changes from one type of macrocycle to the next (e.g. between pre-competition and competition or endurance base and pre-competition periods). The extent to which it does so may well be more than the pre-during pandemic changes that you report, and render your method of assessing pandemic induced change (ie subtract one from the other) less meaningful than it might have been.

Response: We decided to use the year prior to the pandemic to get a representative sample of running over time as opposed to the influence of fluctuations in training. We added this information on lines 95-96.

Another reason why we opted to use the year time-frame is because we will be sending out a follow-up survey in a years’ time to assess running outcomes and injury data. In this way, we will now have equivocal data collection time frames to assess change in injury risk following return to activity from the pandemic.

6. I realise that you have loads of data but the way you present the data in the figures makes it difficult to see exactly what they are. Fig 3AB for example is hard to understand- perhaps you might consider whether there is a better way of showing these data?

Response: We apologize that this image was not clear. We changed the image to a histogram of the responses to better represent the data.

7. Your supplemental data seem to show that you used varying numbers of respondents for the statistical analysis- as the number of responses to each question differed at different points of the survey? Was this the case? In line 135 you state that only complete data were used

Response: Only complete data was used; we had an optional response section for the short-responses, so if this section was not completed, we still included that participant as a complete response. For injury data, we assessed proportions of injuries based on the injured participant pool which may reflect a smaller sample. For the supplemental figures, these were used to display the average differences in running behaviors by region in which the entire sample was assessed and displayed. We did not include international respondents in the regression analysis since there was not a sufficient number of respondents in each geographic group and therefore the interpretations would not be appropriate.

8. Some of the legends are incomplete e.g. for Table 2 you mention EC vs WC but I could not see the explanation of the abbreviation, in Table 1 you do not specific units for mileage

Response: We apologize for this omission; we have fixed the legends for the tables accordingly in Table 1, and on line 271 for the caption for Table 2.

9. From your Table 3 and using the reasoning that you proposed/used elsewhere (divide the values for a year by 4, if I understood that correctly) the injury n was higher for both sprains and strains before the pandemic than it was during (30 vs. 27 and 81.75 vs. 80), apart from in the case of fractures (14.5 vs 8). This isn’t discussed. It contradicts your conclusion in the abstract. Unless you did not in fact analyse complete data sets as noted in the paper? (or I have misunderstood in which please accept my apologies for this point).

Response: We apologize, the entire sample was used, there was a typo when entering in the reported percentage of reported injuries in context to the entire sample in the text, the percentage is now fixed on line 282. For additional clarity in the subsequent percentage break-downs in Table 3, we looked at the proportion of injured respondents and assessed injury type breakdown within the injured pool. The overall injury percentage was taken as a part of the entire sample; however, the injury type/location proportion was based on the injury sample. We have now explicitly explained this in the text on lines 173-174. Although the number of injuries was higher, the proportion of these injuries to adjust for time was higher during the pandemic. We believe that the differences in the raw numbers are attributed to the time frame of exposure, which is a delimitation to this study and why we only discussed proportions in the manuscript. We have now explained this point on lines 287-288.

10. Some of your discussion goes over stuff that you have not included in the results. I would revisit both sections accordingly.

Response: Thank you for bringing this to our attention, we have made appropriate changes on lines 149, and 204.

Thank you in advance for the clarifications.

Best wishes

Thank you very much again for taking the time to review this manuscript.

Responses to Reviewer 2

Reviewer #2: This manuscript investigates the effect of COVID-19 on running behaviors and motivation, using an international survey.

I found the paper to be generally well written. The manuscript addresses a very relevant and important topic. Overall, the methods section is detailed, although some important remarks need to be considered to strengthen the paper. The results are clear and comprehensive. However, some concerns relating to the statistical analysis and interpretations of the results are present, which should be revised before considering publication.

Response: We would like to thank you for taking the time to review our manuscript, and we appreciate the comments and suggestions to improve the paper. We have addressed the specific concerns below to the best of our ability.

2.1. General comments:

1. The main concern relates to the representativeness of the survey. A convenience sample was used in the survey, without prior calculation of the number of participants needed for the survey to be representative for the targeted population (i.e. international runners). The manuscript should be revised while integrating this reflection, both in the methods, results and discussion. This prevents the interested reader from misinterpreting the results and providing a sound answer to the question: "Are these results able to represent the behavior of the complete population (if yes, include total error of the survey), or are these results to be interpreted as descriptive for the included sample."

Response: We agree that based on the sample of convenience that we cannot extrapolate these outcomes to the running community at large. We included this notion in the methods on line 123, results on line 200, and discussion on lines 324-325, 398-399, and 466-469. We also adjusted our title so as not to mislead the audience given that the majority of responses were from the US.

2. Data-analysis: the authors select the paired t-test, without description whether or not the required conditions were fulfilled. Also, please provide more detail in the survey analysis (i.e. depending on data level, processing of open answers)

Response: Thank you for raising this concern, we assessed the data for normality, the sample data were numeric and continuous, and the t-test was most appropriate since the outcomes were collected for the same participants just assessing at different timepoints (repeated measures). We included a statement about this in the statistical analysis section now on lines 149-151, and 153-154. We also provided additional details about the open coding process on lines 187-189.

3. Data-analysis: the authors select to adjust injury data at group level and not at individual level. Did the survey not allow to calculate or estimate individual exposure and injury risk? Please provide additional rationale for this extrapolation at group level, because this influences greatly the results.

Response: Unfortunately we were unable to adjust the data at the individual level since we did not take the length of time that the participants were in quarantine in their region in the survey, and since social isolation measures were extremely specific to exact geographical location (even more than, for example, the state level in the US). Therefore, we decided to adjust the injury data at the group level. However, we will be conducting a follow-up study one year after the original survey was sent out to assess injury data to get a more sensitive estimate of injury data following the pandemic as the time frames will be the same as the year before the pandemic to the year following. We included this limitation on lines 452-458.

Additional comments:

- Injury definition of running related injuries: please elaborate on how recall bias influences injury data throughout the survey. Overuse injuries (running related injuries) are susceptible for this kind of bias and are dependent of the selected injury definition.

Response: We agree this is an important area to highlight in the manuscript. We kept the injury inclusion for this study broad, and aimed to capture more specific injury information about the injury types by body part in the table included in the survey. We did not specifically differentiate between overuse and traumatic injuries, however we did collection information on the duration that the injury influenced their running training, as well as time off from injury. We included this information in the methods (lines 116-117), discussion (lines 369-375), and acknowledged in the limitations (lines 460-462).

- The survey aims to include international runners, but the COVID-quarantine differs in each country / region. This conflicts with earlier comment on representativeness. Consider sub-group analysis for those regions that allow for a more representative analysis?

Response: While we did have international respondents for this study, we were not able to include international respondents as a sub-group in the regression analysis since there was not a sufficient number of respondents in each geographic group and therefore the interpretations would not be appropriate (lines 398-399). Instead, we included the breakdown of responses by geographical location, and changes in running outcomes by geographical location in the supplemental material. We also adjusted the title as noted in a previous response to address this matter.

- The survey included all levels of runners, but the level (competition or recreational) can be of great influence to motivation. Group analysis might conceal sub-group differences? Did the authors consider sub-group analysis for motivation?

Response: We certainly agree that running level can influence motivations. Unfortunately, there was not an explicit question asking what the runners’ primary reason for participation was, instead we asked that runners selected all reasons that applied for their motives for running training (please see supplemental survey included in this revision). We did determine from this questions that 200 respondents (17%) indicated they did compete/race, however only 23 solely responded that their motives for running were competition alone without recreational motives also selected. Therefore, there was not a sufficient sample to assess this influence directly. Instead, we looked at the influence of experience in the regression analysis. We noted this notion as a limitation on lines 462-465.

- How reliable are the exposure, injury and training data? Can the authors provide some additional insights in this matter?

Response: We acknowledge that these data are influenced by recall bias given the nature of the study. We believe that the exposure/training data are reliable given that 90% of our sample used technology to track their runs, and therefore had concrete data to support their mileage and training behaviors. For the injury data, we relied on self-report from participants. Since we included the year prior to the study and only injuries that were resultant from running training, we attempted to minimize recall bias and capture relevant injury data. We did acknowledge these limitations in the manuscript on lines 449-450.

- Results: what about the re-injuries or chronic injuries? How were these processed during data-analysis?

Response: We did not explicitly ask if injuries were re-injuries or chronic injuries in the survey, however we did covary for previous injury in the regression analysis to determine the influence of previous/recurrent injury on predicting injury during the pandemic, however the regression model was not significant (lines 290-291). We did obtain the length of time taken off from injury, which was listed on lines 283-285. This may provide some additional injury insights. We also did assess for injury types, and typically the bony injuries and injuries in the “other” categories were overuse injury types (i.e. table 3, lower limb bony injuries were stress fractures, and the other categories for knee and lower leg were primarily patellofemoral pain and medial tibial stress syndrome respectively). We included this information in the manuscript on lines 369-375. We acknowledged re-injury and injury chronicity as a limitation on lines 460-462.

- Discussion: The decreased intensity seems to contradict the increased injury risk? This is to be interpreted in the broader context of training volume; including both training intensity and frequency, so please discuss this interaction more extensively.

Response: Thank you for raising this point; our theory is that runners opted to increase total running distance and volume, thereby increasing their exposure to loading and potentially increasing the risk of bony/overuse injuries. While increasing intensity has been related to increased acute injuries, we believed that decreasing typical running intensity would actually adversely affect chronic training adaptations, specifically with muscle tone and protection against lower extremity stress-related injuries. Therefore, if runners were transitioning from typical interval training to adding more long-duration higher volume runs, this would be a contributing factor to higher injury rates. We explained this further in the manuscript discussion on lines 345-348.

- Discussion: see above, please reflect on the representativeness and/or margin of error of the survey, relating to either the entire population or the included sample.

Response: Based on previous comments, we have adjusted the discussion accordingly on lines 324-325, 398-399, and in the limitations on lines 468-469.

Thank you again for taking the time to review this manuscript.

Attachment

Submitted filename: PLOSONE_Response_to_Reviewers_R1.docx

Decision Letter 1

Maria Francesca Piacentini

30 Sep 2020

PONE-D-20-18783R1

Running behaviors, motivations, and injury risk during the COVID-19 pandemic: A survey of 1147 runners

PLOS ONE

Dear Dr. DeJong,

Thank you for submitting your manuscript to PLOS ONE. After careful consideration, we feel that it has merit but does not fully meet PLOS ONE’s publication criteria as it currently stands. Therefore, we invite you to submit a revised version of the manuscript that addresses the points raised during the review process.

There are still minor issues that the reviewers would like to see addressed

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If applicable, we recommend that you deposit your laboratory protocols in protocols.io to enhance the reproducibility of your results. Protocols.io assigns your protocol its own identifier (DOI) so that it can be cited independently in the future. For instructions see: http://journals.plos.org/plosone/s/submission-guidelines#loc-laboratory-protocols

We look forward to receiving your revised manuscript.

Kind regards,

Maria Francesca Piacentini

Academic Editor

PLOS ONE

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Reviewers' comments:

Reviewer's Responses to Questions

Comments to the Author

1. If the authors have adequately addressed your comments raised in a previous round of review and you feel that this manuscript is now acceptable for publication, you may indicate that here to bypass the “Comments to the Author” section, enter your conflict of interest statement in the “Confidential to Editor” section, and submit your "Accept" recommendation.

Reviewer #1: (No Response)

Reviewer #2: All comments have been addressed

**********

2. Is the manuscript technically sound, and do the data support the conclusions?

The manuscript must describe a technically sound piece of scientific research with data that supports the conclusions. Experiments must have been conducted rigorously, with appropriate controls, replication, and sample sizes. The conclusions must be drawn appropriately based on the data presented.

Reviewer #1: Partly

Reviewer #2: Partly

**********

3. Has the statistical analysis been performed appropriately and rigorously?

Reviewer #1: Yes

Reviewer #2: No

**********

4. Have the authors made all data underlying the findings in their manuscript fully available?

The PLOS Data policy requires authors to make all data underlying the findings described in their manuscript fully available without restriction, with rare exception (please refer to the Data Availability Statement in the manuscript PDF file). The data should be provided as part of the manuscript or its supporting information, or deposited to a public repository. For example, in addition to summary statistics, the data points behind means, medians and variance measures should be available. If there are restrictions on publicly sharing data—e.g. participant privacy or use of data from a third party—those must be specified.

Reviewer #1: Yes

Reviewer #2: Yes

**********

5. Is the manuscript presented in an intelligible fashion and written in standard English?

PLOS ONE does not copyedit accepted manuscripts, so the language in submitted articles must be clear, correct, and unambiguous. Any typographical or grammatical errors should be corrected at revision, so please note any specific errors here.

Reviewer #1: Yes

Reviewer #2: Yes

**********

6. Review Comments to the Author

Please use the space provided to explain your answers to the questions above. You may also include additional comments for the author, including concerns about dual publication, research ethics, or publication ethics. (Please upload your review as an attachment if it exceeds 20,000 characters)

Reviewer #1: Thank you for your revised paper and replies to my comments.

A few points:

Line 10, 152, 205. Student´s t test

L13, 284. Sentences should never start with a number in numerical format.

L52, 165, 191, 206, 377 Something wrong with the text- part of it seems to be cut off

L56 moulding?

L73, 88, 89, 116 etc RRI´s (you left out the apostrophe)

L130-131, 132, 196-198, 301 “participants residing in all countries”, “through June”, “about participants’ perceived impact the pandemic had on”, “participants that” are ungrammatical

L155 as compared to

L178 “put into in the model” needs to be corrected

Table 1 units incomplete (e.g. non for pace)

I think you should explicitly state that injury was not defined in the survey

Thank you.

Reviewer #2: Thank you for your thorough revision of the manuscript and your honest and clear responses. Although the study protocol and collected data did not allow all concerns to be fully remediated, the authors have listed these as a study limitation and revised the manuscript and conclusions accordingly whenever possible. I think the editor is now best suited to evaluate the manuscript. If the manuscript still fits the scope and policy of Plos One, I could consent with accepting this manuscript for publication.

**********

7. PLOS authors have the option to publish the peer review history of their article (what does this mean?). If published, this will include your full peer review and any attached files.

If you choose “no”, your identity will remain anonymous but your review may still be made public.

Do you want your identity to be public for this peer review? For information about this choice, including consent withdrawal, please see our Privacy Policy.

Reviewer #1: No

Reviewer #2: No

[NOTE: If reviewer comments were submitted as an attachment file, they will be attached to this email and accessible via the submission site. Please log into your account, locate the manuscript record, and check for the action link "View Attachments". If this link does not appear, there are no attachment files.]

While revising your submission, please upload your figure files to the Preflight Analysis and Conversion Engine (PACE) digital diagnostic tool, https://pacev2.apexcovantage.com/. PACE helps ensure that figures meet PLOS requirements. To use PACE, you must first register as a user. Registration is free. Then, login and navigate to the UPLOAD tab, where you will find detailed instructions on how to use the tool. If you encounter any issues or have any questions when using PACE, please email PLOS at figures@plos.org. Please note that Supporting Information files do not need this step.

PLoS One. 2021 Feb 12;16(2):e0246300. doi: 10.1371/journal.pone.0246300.r004

Author response to Decision Letter 1


30 Sep 2020

Reviewer #1: Thank you for your revised paper and replies to my comments.

Response: We would like to thank Reviewer 1 for taking the time to review the revised manuscript. We addressed all specific comments below.

A few points:

Line 10, 152, 205. Student´s t test

Response: Paired t-tests were changed to Student’s t-tests on lines 10, 153, 166, 206, 213.

L13, 284. Sentences should never start with a number in numerical format.

Response: The sentence structure was adjusted on lines 13 and 284.

L52, 165, 191, 206, 377 Something wrong with the text- part of it seems to be cut off Response: We apologize that the text was cut off for the uploaded version, we are unsure what happened as we checked to make sure everything looked in order on the submission. There does not appear to be any truncated text on this modification, we apologize again for the error.

L56 moulding?

Response: We revised “molding” to “influencing” to enhance clarity.

L73, 88, 89, 116 etc RRI´s (you left out the apostrophe) Response: All instances of “RRIs” have been fixed to “RRI’s”

L130-131, 132, 196-198, 301 “participants residing in all countries”, “through June”, “about participants’ perceived impact the pandemic had on”, “participants that” are ungrammatical Response: We edited each sentence to be grammatically correct.

L155 as compared to

Response: We added “as” to the sentence on line 155.

L178 “put into in the model” needs to be corrected Response: We adjusted this to now read “and put into the model” on line 179.

Table 1 units incomplete (e.g. non for pace)

Response: We added in all units now in Table 1.

I think you should explicitly state that injury was not defined in the survey Response: We added this information on line 117.

Thank you.

Reviewer #2: Thank you for your thorough revision of the manuscript and your honest and clear responses. Although the study protocol and collected data did not allow all concerns to be fully remediated, the authors have listed these as a study limitation and revised the manuscript and conclusions accordingly whenever possible. I think the editor is now best suited to evaluate the manuscript. If the manuscript still fits the scope and policy of Plos One, I could consent with accepting this manuscript for publication.

Response: We would like to thank Reviewer 2 for taking the time to review the revised manuscript, and for your feedback and comments throughout this process.

Attachment

Submitted filename: R2_Response_to_Reviewers.docx

Decision Letter 2

Daniel Boullosa

18 Jan 2021

Running behaviors, motivations, and injury risk during the COVID-19 pandemic: A survey of 1147 runners

PONE-D-20-18783R2

Dear Dr. DeJong,

We’re pleased to inform you that your manuscript has been judged scientifically suitable for publication and will be formally accepted for publication once it meets all outstanding technical requirements.

Within one week, you’ll receive an e-mail detailing the required amendments. When these have been addressed, you’ll receive a formal acceptance letter and your manuscript will be scheduled for publication.

An invoice for payment will follow shortly after the formal acceptance. To ensure an efficient process, please log into Editorial Manager at http://www.editorialmanager.com/pone/, click the 'Update My Information' link at the top of the page, and double check that your user information is up-to-date. If you have any billing related questions, please contact our Author Billing department directly at authorbilling@plos.org.

If your institution or institutions have a press office, please notify them about your upcoming paper to help maximize its impact. If they’ll be preparing press materials, please inform our press team as soon as possible -- no later than 48 hours after receiving the formal acceptance. Your manuscript will remain under strict press embargo until 2 pm Eastern Time on the date of publication. For more information, please contact onepress@plos.org.

Kind regards,

Daniel Boullosa

Academic Editor

PLOS ONE

Additional Editor Comments (optional):

Reviewers' comments:

Reviewer's Responses to Questions

Comments to the Author

1. If the authors have adequately addressed your comments raised in a previous round of review and you feel that this manuscript is now acceptable for publication, you may indicate that here to bypass the “Comments to the Author” section, enter your conflict of interest statement in the “Confidential to Editor” section, and submit your "Accept" recommendation.

Reviewer #1: All comments have been addressed

Reviewer #2: All comments have been addressed

**********

2. Is the manuscript technically sound, and do the data support the conclusions?

The manuscript must describe a technically sound piece of scientific research with data that supports the conclusions. Experiments must have been conducted rigorously, with appropriate controls, replication, and sample sizes. The conclusions must be drawn appropriately based on the data presented.

Reviewer #1: Partly

Reviewer #2: Partly

**********

3. Has the statistical analysis been performed appropriately and rigorously?

Reviewer #1: Yes

Reviewer #2: Yes

**********

4. Have the authors made all data underlying the findings in their manuscript fully available?

The PLOS Data policy requires authors to make all data underlying the findings described in their manuscript fully available without restriction, with rare exception (please refer to the Data Availability Statement in the manuscript PDF file). The data should be provided as part of the manuscript or its supporting information, or deposited to a public repository. For example, in addition to summary statistics, the data points behind means, medians and variance measures should be available. If there are restrictions on publicly sharing data—e.g. participant privacy or use of data from a third party—those must be specified.

Reviewer #1: Yes

Reviewer #2: Yes

**********

5. Is the manuscript presented in an intelligible fashion and written in standard English?

PLOS ONE does not copyedit accepted manuscripts, so the language in submitted articles must be clear, correct, and unambiguous. Any typographical or grammatical errors should be corrected at revision, so please note any specific errors here.

Reviewer #1: Yes

Reviewer #2: Yes

**********

6. Review Comments to the Author

Please use the space provided to explain your answers to the questions above. You may also include additional comments for the author, including concerns about dual publication, research ethics, or publication ethics. (Please upload your review as an attachment if it exceeds 20,000 characters)

Reviewer #1: (No Response)

Reviewer #2: (No Response)

**********

7. PLOS authors have the option to publish the peer review history of their article (what does this mean?). If published, this will include your full peer review and any attached files.

If you choose “no”, your identity will remain anonymous but your review may still be made public.

Do you want your identity to be public for this peer review? For information about this choice, including consent withdrawal, please see our Privacy Policy.

Reviewer #1: No

Reviewer #2: No

Acceptance letter

Daniel Boullosa

25 Jan 2021

PONE-D-20-18783R2

Running behaviors, motivations, and injury risk during the COVID-19 pandemic: A survey of 1147 runners

Dear Dr. DeJong:

I'm pleased to inform you that your manuscript has been deemed suitable for publication in PLOS ONE. Congratulations! Your manuscript is now with our production department.

If your institution or institutions have a press office, please let them know about your upcoming paper now to help maximize its impact. If they'll be preparing press materials, please inform our press team within the next 48 hours. Your manuscript will remain under strict press embargo until 2 pm Eastern Time on the date of publication. For more information please contact onepress@plos.org.

If we can help with anything else, please email us at plosone@plos.org.

Thank you for submitting your work to PLOS ONE and supporting open access.

Kind regards,

PLOS ONE Editorial Office Staff

on behalf of

Dr. Daniel Boullosa

Academic Editor

PLOS ONE

Associated Data

    This section collects any data citations, data availability statements, or supplementary materials included in this article.

    Supplementary Materials

    S1 Fig. (A) Percentage of respondents by state within the United States, (B) percentage of respondents by country, (C) responses by state: change in number of sustained runs, (D) responses by country: change in number of sustained runs, (E) responses by state: change in number of running workouts, (F) responses by country: change in number of running workouts.

    Abbreviations: Avg, Average; Diff, Difference; N, number.

    (TIF)

    S1 File. Running behaviors before and during the COVID-19 pandemic survey.

    List of questions and response options included in the survey. Question logic was used to skip irrelevant questions and displayed within the document.

    (DOCX)

    S1 Table. Open coding short response items.

    The words or phrases that most frequently occurred in short responses were grouped into like categories and displayed in the table, along with number of instances noted throughout the short responses.

    (DOCX)

    Attachment

    Submitted filename: PLOSONE_Response_to_Reviewers_R1.docx

    Attachment

    Submitted filename: R2_Response_to_Reviewers.docx

    Data Availability Statement

    Due to ethical restrictions, the data underlying this study may not be shared publicly. Data are available from the University of Virginia Ethics Committee (contact via Jeffrey Monroe, mjm6ny@virginia.edu) for researchers who meet the criteria for access to confidential data.


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