Abstract
Walking cadence (steps/min) is associated with intensity of ambulatory behavior. This analysis provides normative values for peak 30-min cadence, an indicator of “natural best effort” during free-living behavior. A sample of 1,196 older adults (60–85+ years) with accelerometer data from the National Health and Nutrition Examination Survey 2005–2006 was used. Peak 30-min cadence was calculated for each individual. Quintile-defined values were computed, stratified by sex and age groups. Smoothed sex-specific centile curves across the age-span were fitted using the LMS method. Peak 30-min cadence generally trended lower as age increased. The uppermost quintile value was >85 steps/min (men 60–64 years), the lowermost was <22 steps/min (women 85+ years). The highest 95th centile value was 103 steps/min (men 64–70 years), the lowest 5th centile value was 15 steps/min (women 85+ years). These normative values may be useful for evaluating older adults’ “natural best effort” during free-living ambulatory behavior.
Keywords: accelerometer, walking, steps per min, wearable
There is growing interest in measuring ambulatory physical activity, reported as steps/day, with the recent 2018 Physical Activity Guidelines Advisory Committee Scientific Report (2018 Physical Activity Guidelines Advisory Committee, 2018) noting the advantages of step-based physical activity recommendations. A step is an intuitive unit of human behavior that is captured by the vast majority of contemporary wearable technologies, including both research- and consumer-grade devices. In addition, step-based measures of physical activity are commonly understood by researchers, clinicians, and the general public.
Previous studies have reported normative (reference) values for steps/day in children (Barreira et al., 2015), adults (Tudor-Locke, Johnson, & Katzmarzyk, 2009), and older adults (Tudor-Locke et al., 2013) using the NHANES 2005–2006 Physical Activity Monitoring (PAM) data, a United States population representative sample. While steps/day is a useful indicator of the volume of ambulatory physical activity performed, it does not capture the intensity of enacted ambulatory (stepping) behavior, an important tenet of physical activity guidelines (U.S. Department of Health and Human Services, 2008). Walking cadence (steps/min), a temporal parameter of gait, has been associated with intensity of walking behavior, whereby higher cadences elicit greater intensities (Tudor-Locke & Rowe, 2012). Accelerometers provide access to time-stamped data at higher resolutions, allowing for detailed analysis of free-living ambulatory physical activity over smaller time-frames, e.g., cadence (steps accumulated in 1 min; steps/min). Peak 30-min cadence, a step-based physical activity index (i.e., indicator, signpost, guide) that represents the “natural best effort” for cadence across a day (Tudor-Locke, Brashear, Katzmarzyk, & Johnson, 2012), has emerged as a method of describing free-living ambulatory physical activity data. Peak 30-min cadence is defined as the average steps/min recorded for the 30 highest cadence values (not necessarily consecutive) in a day, averaged over the monitoring time frame. It is shaped by both the intensity and persistence of stepping behavior within a day, as well as its consistency (regularity) across a week. As such, it represents the “natural best effort” in terms of free-living ambulatory (stepping) behavior.
Peak cadence indices have been employed to describe the natural best effort for free-living ambulatory behavior for children (Barreira, Katzmarzyk, Johnson, & Tudor-Locke, 2012, 2013; Barreira et al., 2015) and adults (Tudor-Locke, Brashear, et al., 2012) using the NHANES 2005–2006 PAM data. However, peak-30 min cadence values representing the full spectrum of behavior (i.e., lowest to highest observed values) in older adults (≥60 years of age) have not been reported. Therefore, the purpose of this analysis was to provide centile values for peak 30-min cadence in older adults, stratified by sex and age groups, from the nationally representative NHANES 2005–2006 PAM data. This tabulation of peak 30-min cadence extends beyond a single central tendency measure of peak 30-min cadence, and as such will be useful as normative (reference) data for interpreting accelerometer-determined physical activity data in older adults.
Methods
NHANES Physical Activity Monitoring
The protocols used in the NHANES 2005–2006 PAM component are available from the following website - http://www.cdc.gov/nchs/data/nhanes/nhanes_05_06/BM.pdf. A catalog of data treatment rules, variables and definitions for the NHANES 2005–2006 PAM data used by researchers is also available elsewhere (Tudor-Locke, Camhi, & Troiano, 2012). Briefly, the survey deployed the ActiGraph 7164 (ActiGraph, Pensacola, FL) accelerometer to assess free-living physical activity, including stepping behavior. Participants were asked to wear the device for 7 days, during all waking hours, with allowances to remove the device during water-based activities (e.g., showering, swimming) and while sleeping. Notably, although subsequent rounds of the NHANES have been conducted, the PAM 2005–2006 survey remains the preeminent source of nationally representative and objectively monitored step-based physical activity data in the United States. The NHANES 2005–2006 PAM protocols were approved by the National Center for Health Statistics ethics review board, and all participants provided informed consent.
Data Treatment
Similar to the majority of studies that have used the NHANES 2005–2006 PAM data (Tudor-Locke, Camhi, et al., 2012), the National Cancer Institute’s SAS macro http://riskfactor.cancer.gov/tools/nhanes_pam/) was applied to the ActiGraph 7164 data. A valid day was defined as ≥10 monitored h/day, with non-wear time defined as ≥60 minutes of consecutive zero activity counts/min, allowing for minimal interruptions (up to 2 min of counts between 0 and 100) (Troiano et al., 2008). All individuals with at least one valid day of data were retained in the analysis (Tudor-Locke et al., 2009).
Statistical Analysis
Analytic Sample
The analytic sample consisted of 1196 older adults, representing 88% of the originally eligible sample from the NHANES 2005–2006 PAM dataset (n=1359). Participant data excluded from this analysis comprised: NHANES-designated unreliable PAM data (n=54); accelerometers shown to be out of calibration upon return (n=61), or no valid days (≥10 h/day) of accelerometer wear-time (n=48).
Descriptive Characteristics
Descriptive characteristics (mean and standard error) included: age (years), height (cm), body mass (kg), body mass index (BMI; kg/m2); and proportions classified in race/ethnicity categories (non-Hispanic white, non-Hispanic black, Mexican American, other Hispanic, other race [including multi-racial]) and BMI categories (underweight <18.5, normal weight 18.5–24.9, overweight 25.0–29.9, and obese ≥30.0 kg/m2). In addition, NHANES Examination Data and Laboratory Data were used to provide a general indication of the cardiometabolic health status of the sample (e.g., blood pressure, glycated hemoglobin [HbA1C], waist circumference, and self-reported diabetes prevalence [type unspecified]). Sample characteristics are stratified by sex in 5-year age groups (60–64, 65–69, 70–74, 75–79, 80–84, and 85+ years of age). Descriptive characteristics were calculated using R (RStudio: Integrated Development for R. RStudio, Inc., Boston, MA). Where appropriate, the R package ‘survey’ was used to account for the complex, multi-stage probability design of the NHANES.
Peak 30-min Cadence (Steps/min)
Peak 30-min cadence was determined following the method established in previous analyses conducted with data from children (Barreira et al., 2012; Barreira et al., 2015) and adults (Tudor-Locke, Brashear, et al., 2012). For each participant, accelerometer-determined steps (stored in 1-min epochs) were first rank ordered within each day. Next, we calculated the average steps/min for the highest 30 (not necessarily consecutive) minutes for each day, and then calculated the mean of this value across all valid days.
Normative values – Quintiles
Quintile-defined categories for peak 30-min cadence (lowest [<20th centile], below average [20th to <40th centile], average [40th to <60th centile], above average [60th to <80th centile], and highest [≥80th centile]) were calculated for the whole sample and also by sex and age groups (60–64, 65–69, 70–74, 75–79, 80–84, and 85+ years).
Normative values - LMS Curves
LMS ChartMakerPro (v 2.54; The Institute of Child Health, London, United Kingdom) was used to produce smoothed centile curves for peak 30-min cadence (5th to 95th centile in 5 percent increments) using the LMS method (Cole & Green, 1992). Briefly, LMS smoothing is a standard analytical technique used to manage the naturally erratic distribution of data as it changes according to a covariate (e.g., across the age spectrum) (Kuczmarski et al., 2002). The resulting smoothed reference centile curves are more useful for clinical applications, such as child growth charts for anthropometric characteristics including height, weight, circumferences, and body composition (Cole, 1990; Cole & Green, 1992). This method has previously been used to produce normative centile values and curves for steps/day and peak cadence in children (Barreira et al., 2015) and for steps/day in older adults (Tudor-Locke et al., 2013) using the NHANES 2005–2006 PAM data. A detailed description of the LMS method employed herein can be found in the aforementioned manuscripts. LMS centile and quintile values for peak 30-minute cadence were rounded the nearest whole number for pragmatic reasons, i.e., to aid with clinical evaluation and comparison.
Results
Descriptive Characteristics
Descriptive characteristics of the analytic sample (n=1196) are reported in Table 1. Across sex and age groups, the sample was mostly non-Hispanic white (75.0–95.0%,) with smaller representations of non-Hispanic black (1.4–11.6%), Mexican Americans (1.7–5.2%), other Hispanic (0.0–4.5%) and other race/ethnicities (0.0–6.8%). The sample could be generally classified as being at risk for cardiometabolic disease based on various risk factors (cut-offs and references below). Specifically, the sample had (on average): an overweight BMI (≥ 25 kg/m2; National Institutes of Health, 1998), a large waist circumference (women: ≥ 80 cm, men: ≥ 102 cm; Alberti et al., 2009), elevated systolic blood pressure values generally consistent with stage 1 hypertension (130–139 mm Hg; Whelton et al., 2018), and elevated glycated hemoglobin (HbA1C) values consistent with prediabetes (≥ 6.5%; American Diabetes, 2018). In addition, based on self-report data, 20.1% of the sample indicated they had diabetes (type unspecified), 2.8% were borderline, 77% were free from diabetes, and 0.1% did not know their status. Accelerometer wear time (mean ± standard error) was 13.9 ± 0.1 h/day (95% CI: 13.6–14.1) over 5.8 ± 0.1 valid days. Men accrued ~16 min/day more wear time than women (p = 0.02).
Table 1.
Demographic characteristics of the sample, stratified by sex and age groups: NHANES 2005–2006
| 60–64 y | 65–69 y | 70–74 y | 75–79 y | 80–84 y | 85+ y | |||||||
|---|---|---|---|---|---|---|---|---|---|---|---|---|
| M | F | M | F | M | F | M | F | M | F | M | F | |
| N | 147 | 161 | 127 | 124 | 116 | 105 | 88 | 64 | 92 | 76 | 41 | 55 |
| Age (y) | 62.2 (0.1) | 61.9 (0.2) | 66.8 (0.2) | 66.8 (0.2) | 71.9 (0.1) | 71.9 (0.1) | 77.1 (0.1) | 76.8 (0.2) | 81.8 (0.2) | 81.9 (0.1) | 85.0+ a | 85.0+ a |
| Height (cm) | 175.3 (0.6) | 162.1 (0.6) | 173.8 (0.8) | 160.8 (0.7) | 174.2 (1.0) | 160.5 (0.7) | 173.0 (0.8) | 159.0 (0.7) | 171.4 (0.5) | 157.3 (1.0) | 172.2 (1.0) | 154.7 (1.0) |
| Body mass (kg) | 89.4 (1.6) | 78.4 (2.0) | 88.4 (1.9) | 77.3 (2.1) | 87.7 (1.8) | 72.3 (2.9) | 85.1 (1.5) | 66.0 (2.5) | 77.6 (0.8) | 67.9 (1.8) | 75.8 (1.7) | 61.7 (1.6) |
| BMI (kg/m2) | 29.1 (0.6) | 29.8 (0.7) | 29.1 (0.5) | 29.7 (0.7) | 28.9 (0.4) | 28.1 (1.1) | 28.4 (0.5) | 26.2 (1.0) | 26.4 (0.3) | 27.5 (0.6) | 25.8 (0.6) | 25.8 (0.6) |
| Waist circumference (cm) | 105.5 (1.6) | 99.0 (1.7) | 106.9 (1.4) | 99.6 (0.9) | 106.9 (1.4) | 95.2 (2.6) | 107.0 (1.4) | 92.0 (2.0) | 100.3 (0.8) | 96.5 (1.7) | 100.5 (1.6) | 91.7 (1.8) |
| Systolic blood pressure (mmHg) | 131.7 (2.2) | 131.0 (2.5) | 131.6 (1.2) | 133.9 (1.8) | 130.7 (1.4) | 138.9 (2.0) | 129.1 (2.0) | 138.3 (2.5) | 136.7 (1.8) | 150.0 (3.0) | 136.6 (3.3) | 145.9 (3.4) |
| Diastolic blood pressure (mmHg) | 72.3 (1.1) | 69.5 (1.5) | 68.8 (1.6) | 71.1 (1.0) | 65.9 (1.4) | 63.8 (1.7) | 64.9 (1.7) | 61.2 (2.5) | 64.8 (1.5) | 57.8 (2.8) | 57.8 (4.1) | 60.6 (2.9) |
| HbA1C (%) | 5.9 (0.2) | 5.8 (0.1) | 5.9 (0.1) | 5.7 (0.0) | 5.8 (0.1) | 5.7 (0.0) | 5.8 (0.1) | 5.8 (0.1) | 5.7 (0.1) | 5.8 (0.1) | 5.6 (0.0) | 5.6 (0.1) |
| BMI category | ||||||||||||
| Underweight (%) | 1.7 (1.3) | 0.0 (0.0) | 0.3 (0.3) | 2.1 (1.5) | 1.3 (1.0) | 2.8 (1.7) | 0.0 (0.0) | 7.1 (3.7) | 1.9 (1.4) | 1.3 (1.3) | 3.0 (2.6) | 0.0 (0.0) |
| Normal weight (%) | 17.2 (4.6) | 28.1 (3.4) | 21.8 (4.7) | 25.9 (6.1) | 18.5 (2.4) | 36.7 (4.5) | 26.8 (5.1) | 39.2 (9.2) | 39.4 (4.3) | 34.8 (6.1) | 37.1 (10.7) | 52.2 (7.8) |
| Overweight (%) | 45.1 (4.9) | 31.5 (4.5) | 40.7 (6.5) | 34.0 (5.6) | 47.7 (4.8) | 28.9 (5.4) | 38.6 (7.8) | 30.5 (4.4) | 41.8 (7.2) | 32.8 (3.7) | 47.7 (9.4) | 32.1 (6.9) |
| Obese (%) | 36.0 (5.3) | 40.5 (4.6) | 37.2 (5.4) | 38.0 (4.9) | 32.6 (4.1) | 31.6 (7.0) | 34.6 (5.1) | 23.2 (6.7) | 16.9 (4.6) | 31.1 (5.0) | 12.3 (5.8) | 15.6 (4.3) |
| Ethnicity/race | ||||||||||||
| Mexican-American (%) | 4.1 (1.1) | 5.2 (1.1) | 4.0 (1.2) | 2.9 (0.8) | 5.2 (0.9) | 4.3 (1.6) | 1.9 (0.8) | 2.9 (0.9) | 3.6 (1.5) | 1.7 (1.0) | 2.0 (1.5) | 4.9 (2.3) |
| Other Hispanic (%) | 1.0 (1.0) | 0.0 (0.0) | 4.5 (2.2) | 4.2 (2.1) | 2.0 (1.3) | 0.0 (0.0) | 0.6 (0.6) | 1.4 (1.4) | 1.6 (1.4) | 0.9 (0.9) | 0.0 (0.0) | 0.0 (0.0) |
| Non-Hispanic white (%) | 82.8 (4.0) | 77.8 (4.4) | 75.0 (5.1) | 80.0 (4.2) | 83.3 (3.5) | 85.0 (4.2) | 87.5 (2.7) | 85.8 (3.9) | 90.4 (3.0) | 89.3 (3.8) | 95.0 (2.8) | 84.0 (5.2) |
| Non-Hispanic black (%) | 7.4 (1.8) | 11.6 (3.0) | 9.7 (2.2) | 8.2 (2.0) | 8.9 (2.5) | 10.7 (3.6) | 8.7 (2.7) | 6.2 (1.9) | 3.7 (1.6) | 5.6 (2.2) | 1.4 (1.4) | 7.2 (3.1) |
| Other race, including multi-racial (%) | 4.6 (2.6) | 5.4 (2.3) | 6.8 (3.0) | 4.7 (3.2) | 0.5 (0.5) | 0.0 (0.0) | 1.3 (1.3) | 3.7 (2.8) | 0.7 (0.7) | 2.6 (1.8) | 1.5 (1.5) | 3.9 (2.9) |
Note. BMI = body mass index; F = Female, M = Men, NHANES = National Health and Nutrition Examination Survey, y = years. Values presented as Mean (SE).
No SD values are provided since the ages of each participant in this subgroup are designated as 85+ in the original NHANES dataset.
Normative (reference) values for peak 30-min cadence
Quintile categories
Table 2 displays peak 30-min cadence values for the respective quintile categories (lowest, below average, average, above average and highest), stratified by sex and age. The uppermost quintile value observed for men (>85 steps/min) was for 60–64 year olds, and the lowermost value (<31 steps/min) was for 85+ year olds. For women, the uppermost quintile value (>81 steps/min) was for 60–64 year olds, and the lowermost quintile (<22 steps/min) was for 85+ year olds. In general, peak 30-min cadence tended to decrease within each quintile category as age advanced, however there were some exceptions to this trend. For example, peak 30-min cadence for the above average quintile was marginally higher (but practically similar) for men aged 80–84 years (57–66 steps/min) and 75–79 years (55–66 steps/min). Furthermore, the highest quintile for men aged 80–84 years was slightly greater (>66 steps/min) in comparison to 75–79 year olds (>65 steps/min). For women, peak 30-min cadence values for the average (54–63 vs 51–63 steps/min) and above average (64–80 vs 64–78 steps/min) quintiles were marginally higher (but again practically similar) for 70–74 and 66–69 year olds, respectively. In addition, the highest quintile for women aged 70–74 years was slightly greater (>80 steps/min) than that for 65–69 year olds (>78 steps/min).
Table 2.
Quintile-defined normative (reference) categories for peak 30-min cadence (steps/min) for older adults (60–85+ years) stratified by sex and age groups: NHANES 2005–2006
| Peak 30-min cadence (steps/min) |
|||||
|---|---|---|---|---|---|
| Age group | Lowest | Below Average | Average | Above Average | Highest |
| All (years) | |||||
| 60–64 | <51 | 51–62 | 63–73 | 74–84 | >84 |
| 65–69 | <44 | 44–55 | 56–66 | 67–80 | >80 |
| 70–74 | <39 | 39–53 | 54–65 | 66–80 | >80 |
| 75–79 | <34 | 34–46 | 47–54 | 55–64 | >64 |
| 80–84 | <28 | 28–40 | 41–50 | 51–63 | >63 |
| 85+ | <23 | 23–29 | 30–38 | 39–52 | >52 |
| Men (years) | |||||
| 60–64 | <53 | 53–65 | 66–75 | 76–85 | >85 |
| 65–69 | <48 | 48–60 | 61–71 | 72–84 | >84 |
| 70–74 | <47 | 47–58 | 59–69 | 70–79 | >79 |
| 75–79 | <36 | 36–50 | 51–54 | 55–65 | >65 |
| 80–84 | <32 | 32–48 | 49–56 | 57–66 | >66 |
| 85+ | <31 | 31–38 | 39–45 | 46–56 | >56 |
| Women (years) | |||||
| 60–64 | <44 | 44–57 | 58–68 | 69–81 | >81 |
| 65–69 | <43 | 43–50 | 51–63 | 64–78 | >78 |
| 70–74 | <37 | 37–51 | 52–63 | 64–80 | >80 |
| 75–79 | <33 | 33–43 | 44–50 | 51–64 | >64 |
| 80–84 | <27 | 27–37 | 38–45 | 46–57 | >57 |
| 85+ | <22 | 22–26 | 27–31 | 32–49 | >49 |
Note. Quintile-defined categories for peak 30-min cadence: lowest (<20th centile), below average (20th to <40th centile), average (40th to <60th centile), above average (60th to <80th centile), and highest (≥80th centile)
LMS Curves
Sex-and-age specific peak 30-min cadence values corresponding to the 5th to 95th centiles are displayed in Tables 3 (men) and 4 (women). Across all ages, mean (± SD) peak 30-min cadence values corresponding to the 5th, 25th, 50th, 75th, and 95th centiles were 29 ± 8, 47 ± 9, 60 ± 9, 74 ± 9, and 95 ± 8 steps/min for men and 24 ± 4, 39 ± 8, 52 ± 10, 67 ± 11, and 92 ± 10 steps/min for women. The LMS curves (Figure 1) displayed two general trends for both men and women, either decreasing steadily with age or remaining relatively stable from ~60–70 years of age and decreasing steadily thereafter. The highest value of peak 30-min cadence for men was observed among 64–70 year olds (all presenting 103 steps/min), and the lowest value (18 steps/min) was for 84 and 85+ year olds. For women, the highest values were observed among 69–71 year olds (all presenting 102 steps/min), and the lowest value (15 steps/min) was for 85+ year olds.
Table 3.
Normative (reference) centile values (LMS method) for peak 30-min cadence (steps/min) for men stratified by age (60–85+ years): NHANES 2005–2006
| Centiles |
||||||||||||||||||||
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Age (y) | n | 5 | 10 | 15 | 20 | 25 | 30 | 35 | 40 | 45 | 50 | 55 | 60 | 65 | 70 | 75 | 80 | 85 | 90 | 95 |
| 60 | 28 | 43 | 49 | 53 | 56 | 59 | 62 | 64 | 66 | 68 | 71 | 73 | 75 | 77 | 79 | 82 | 85 | 88 | 92 | 99 |
| 61 | 28 | 42 | 48 | 52 | 56 | 59 | 61 | 64 | 66 | 68 | 70 | 73 | 75 | 77 | 80 | 82 | 85 | 89 | 93 | 100 |
| 62 | 35 | 41 | 47 | 51 | 55 | 58 | 61 | 63 | 66 | 68 | 70 | 72 | 75 | 77 | 80 | 83 | 86 | 89 | 94 | 101 |
| 63 | 26 | 40 | 46 | 51 | 54 | 57 | 60 | 63 | 65 | 68 | 70 | 72 | 75 | 77 | 80 | 83 | 86 | 90 | 95 | 102 |
| 64 | 30 | 38 | 45 | 50 | 53 | 57 | 59 | 62 | 65 | 67 | 70 | 72 | 75 | 77 | 80 | 83 | 86 | 90 | 95 | 103 |
| 65 | 33 | 37 | 44 | 49 | 52 | 56 | 59 | 61 | 64 | 66 | 69 | 72 | 74 | 77 | 80 | 83 | 86 | 90 | 95 | 103 |
| 66 | 32 | 36 | 43 | 47 | 51 | 55 | 58 | 60 | 63 | 66 | 68 | 71 | 74 | 76 | 79 | 82 | 86 | 90 | 95 | 103 |
| 67 | 22 | 34 | 42 | 46 | 50 | 54 | 57 | 60 | 62 | 65 | 68 | 70 | 73 | 76 | 79 | 82 | 86 | 90 | 95 | 103 |
| 68 | 15 | 33 | 41 | 45 | 49 | 53 | 56 | 59 | 62 | 64 | 67 | 70 | 72 | 75 | 78 | 82 | 85 | 90 | 95 | 103 |
| 69 | 25 | 32 | 40 | 44 | 48 | 52 | 55 | 58 | 61 | 64 | 66 | 69 | 72 | 75 | 78 | 81 | 85 | 89 | 95 | 103 |
| 70 | 25 | 31 | 38 | 43 | 47 | 51 | 54 | 57 | 60 | 62 | 65 | 68 | 71 | 74 | 77 | 80 | 84 | 89 | 94 | 103 |
| 71 | 30 | 30 | 37 | 42 | 46 | 50 | 53 | 56 | 58 | 61 | 64 | 67 | 70 | 73 | 76 | 79 | 83 | 87 | 93 | 102 |
| 72 | 20 | 29 | 36 | 41 | 45 | 48 | 51 | 54 | 57 | 60 | 63 | 66 | 68 | 71 | 74 | 78 | 82 | 86 | 92 | 101 |
| 73 | 24 | 28 | 35 | 40 | 44 | 47 | 50 | 53 | 56 | 59 | 61 | 64 | 67 | 70 | 73 | 76 | 80 | 85 | 91 | 99 |
| 74 | 17 | 27 | 33 | 38 | 42 | 45 | 48 | 51 | 54 | 57 | 59 | 62 | 65 | 68 | 71 | 74 | 78 | 83 | 89 | 97 |
| 75 | 18 | 25 | 32 | 36 | 40 | 43 | 46 | 49 | 52 | 55 | 57 | 60 | 63 | 66 | 69 | 72 | 76 | 80 | 86 | 95 |
| 76 | 18 | 24 | 30 | 35 | 38 | 41 | 44 | 47 | 50 | 52 | 55 | 58 | 60 | 63 | 66 | 70 | 73 | 78 | 83 | 92 |
| 77 | 15 | 23 | 29 | 33 | 37 | 40 | 43 | 45 | 48 | 51 | 53 | 56 | 58 | 61 | 64 | 67 | 71 | 75 | 81 | 89 |
| 78 | 23 | 22 | 28 | 32 | 36 | 39 | 41 | 44 | 47 | 49 | 52 | 54 | 57 | 60 | 63 | 66 | 69 | 74 | 79 | 88 |
| 79 | 14 | 21 | 27 | 31 | 35 | 38 | 41 | 43 | 46 | 48 | 51 | 53 | 56 | 59 | 62 | 65 | 69 | 73 | 78 | 87 |
| 80 | 18 | 21 | 27 | 31 | 34 | 37 | 40 | 43 | 45 | 48 | 50 | 53 | 55 | 58 | 61 | 64 | 68 | 72 | 78 | 87 |
| 81 | 23 | 20 | 26 | 30 | 34 | 37 | 39 | 42 | 45 | 47 | 50 | 52 | 55 | 58 | 61 | 64 | 68 | 72 | 78 | 86 |
| 82 | 23 | 20 | 25 | 29 | 33 | 36 | 39 | 41 | 44 | 46 | 49 | 51 | 54 | 57 | 60 | 63 | 67 | 71 | 77 | 86 |
| 83 | 13 | 19 | 25 | 29 | 32 | 35 | 38 | 40 | 43 | 45 | 48 | 50 | 53 | 56 | 59 | 62 | 66 | 70 | 76 | 84 |
| 84 | 15 | 18 | 24 | 28 | 31 | 34 | 37 | 39 | 42 | 44 | 47 | 49 | 52 | 54 | 57 | 61 | 64 | 69 | 74 | 83 |
| 85+ | 41 | 18 | 23 | 27 | 30 | 33 | 35 | 38 | 40 | 43 | 45 | 48 | 50 | 53 | 56 | 59 | 63 | 67 | 72 | 81 |
Figure 1.
LMS curves for peak 30-min cadence (steps per min) across the age span (60–85+ years) stratified by sex: NHANES 2005–2006.
Discussion
The normative (reference) values for peak 30-min cadence provided herein are indicators of the “natural best effort” during free-living ambulatory (stepping) behavior among older adults. A broad spectrum of behavior was observed across the sex-and-age specific quintiles and centiles, with lower peak 30-min cadence values associated with advancing age for both sexes. We deliberately avoided providing a summary mean peak 30-min cadence point value inclusive of all ages and both sexes in an effort to not overly-simplify the naturally wide variability in physical function and fitness of older adults (i.e., there is no such thing as an “average” older adult across the age span assessed herein). These normative values will be useful for researchers and clinicians interested in comparing older adult step-based accelerometer data against a nationally representative older sample. For example, these normative data may be useful for comparison and interpretation purposes during screening, surveillance and evaluation of older adults’ ambulatory physical activity. Although it is expected that peak 30-min cadence values should decline with advancing age, a more direct comparison against these normative data may inform decisions as to whether the decline is in line with expectations, or more pronounced, such as a shift between quintile categories or centile values as individuals age. Furthermore, benchmarking individuals against normative data provides a point of reference for which an intervention can be used to target a change in behavior and improvement in free-living cadence.
The peak 30-min cadence values presented herein are consistent with the range of values observed in other smaller and non-representative samples of ostensibly healthy older adults. Schuna et al. (2013), reported a mean peak 30-min cadence of 64.4 ± 22.7 steps/min for men, and 63.3 ± 25.5 steps/min among women (n = 143, mean age 71.9 ± 7.9 years, range 58–92 years). Gardner et al. (2007), reported a peak-30 min cadence of 61.6 ± 14.8 steps/min (n = 129, mean age 64 ± 12 years, range 50–90 years; no sex specific data presented). Finally, Gonzales et al. (2015), reported a mean peak 30-min cadence of 76.8 ± 25.0 steps/min for men, and 77.2 ± 29.5 steps/min for women (n = 43, mean age 67.3 ± 5.3 years, range 60–78 years). In comparison to the results from the current analysis, the values presented by Schuna et al. (2013) and Gardner et al. (2007) are comparable to the 50th centile (60 ± 9 steps/min; Table 3 - mean value across all ranges) for men, and between the 50th (52 ± 10 steps/min) and 75th centile (67 ± 11 steps/min) for women (Table 4), whereas the values reported by Gonzales et al. (2015) are closer to the 75th centile for men (78 ± 6 steps/min; Table 3 - mean value for 60–78 year olds) for men, and between the 75th (73 ± 5 steps/min) and 85th centile (82 ± 4 steps/min) for women (Table 4). Differences between studies might be explained by demographic, anthropometric, functional and fitness related characteristics of the underlying samples.
Table 4.
Normative (reference) centile values (LMS method) for peak 30-min cadence (steps/min) for women stratified by age (60–85+ years): NHANES 2005–2006
| Centiles |
||||||||||||||||||||
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Age (y) | n | 5 | 10 | 15 | 20 | 25 | 30 | 35 | 40 | 45 | 50 | 55 | 60 | 65 | 70 | 75 | 80 | 85 | 90 | 95 |
| 60 | 38 | 32 | 39 | 44 | 47 | 51 | 54 | 57 | 59 | 62 | 64 | 67 | 69 | 72 | 75 | 78 | 81 | 85 | 90 | 97 |
| 61 | 34 | 31 | 38 | 43 | 46 | 50 | 53 | 56 | 58 | 61 | 63 | 66 | 69 | 71 | 74 | 77 | 81 | 85 | 90 | 97 |
| 62 | 32 | 30 | 37 | 41 | 45 | 49 | 52 | 55 | 57 | 60 | 62 | 65 | 68 | 70 | 73 | 76 | 80 | 84 | 89 | 97 |
| 63 | 31 | 29 | 36 | 40 | 44 | 48 | 51 | 53 | 56 | 59 | 61 | 64 | 67 | 70 | 73 | 76 | 79 | 84 | 89 | 97 |
| 64 | 26 | 28 | 35 | 39 | 43 | 47 | 50 | 53 | 55 | 58 | 61 | 63 | 66 | 69 | 72 | 75 | 79 | 83 | 89 | 97 |
| 65 | 23 | 27 | 34 | 39 | 42 | 46 | 49 | 52 | 54 | 57 | 60 | 63 | 65 | 68 | 71 | 75 | 79 | 83 | 89 | 97 |
| 66 | 28 | 27 | 33 | 38 | 42 | 45 | 48 | 51 | 54 | 57 | 59 | 62 | 65 | 68 | 71 | 75 | 79 | 83 | 89 | 98 |
| 67 | 34 | 27 | 33 | 38 | 42 | 45 | 48 | 51 | 54 | 57 | 59 | 62 | 65 | 68 | 71 | 75 | 79 | 84 | 90 | 99 |
| 68 | 12 | 26 | 33 | 37 | 41 | 45 | 48 | 51 | 54 | 56 | 59 | 62 | 65 | 68 | 72 | 75 | 79 | 84 | 91 | 101 |
| 69 | 27 | 26 | 32 | 37 | 41 | 44 | 47 | 50 | 53 | 56 | 59 | 62 | 65 | 68 | 72 | 75 | 80 | 85 | 92 | 102 |
| 70 | 25 | 26 | 32 | 37 | 40 | 44 | 47 | 50 | 53 | 56 | 59 | 62 | 65 | 68 | 71 | 75 | 80 | 85 | 92 | 102 |
| 71 | 21 | 25 | 31 | 36 | 40 | 43 | 46 | 49 | 52 | 55 | 58 | 61 | 64 | 67 | 71 | 75 | 79 | 84 | 91 | 102 |
| 72 | 14 | 25 | 31 | 35 | 39 | 42 | 45 | 48 | 51 | 54 | 56 | 59 | 63 | 66 | 69 | 73 | 78 | 83 | 90 | 101 |
| 73 | 21 | 24 | 30 | 34 | 38 | 41 | 44 | 47 | 49 | 52 | 55 | 58 | 61 | 64 | 68 | 72 | 76 | 82 | 89 | 100 |
| 74 | 24 | 24 | 29 | 33 | 37 | 40 | 43 | 45 | 48 | 51 | 54 | 56 | 59 | 63 | 66 | 70 | 75 | 80 | 87 | 98 |
| 75 | 13 | 23 | 28 | 32 | 35 | 38 | 41 | 44 | 46 | 49 | 52 | 55 | 58 | 61 | 64 | 68 | 72 | 78 | 85 | 96 |
| 76 | 17 | 22 | 27 | 31 | 34 | 37 | 40 | 42 | 45 | 47 | 50 | 53 | 55 | 59 | 62 | 66 | 70 | 75 | 82 | 94 |
| 77 | 9 | 22 | 26 | 30 | 33 | 36 | 38 | 41 | 43 | 45 | 48 | 51 | 53 | 56 | 60 | 63 | 68 | 73 | 80 | 91 |
| 78 | 15 | 21 | 26 | 29 | 32 | 34 | 37 | 39 | 41 | 44 | 46 | 49 | 51 | 54 | 57 | 61 | 65 | 70 | 77 | 88 |
| 79 | 10 | 21 | 25 | 28 | 31 | 33 | 35 | 38 | 40 | 42 | 45 | 47 | 50 | 52 | 56 | 59 | 63 | 68 | 75 | 86 |
| 80 | 14 | 20 | 24 | 27 | 30 | 32 | 34 | 36 | 39 | 41 | 43 | 46 | 48 | 51 | 54 | 57 | 61 | 66 | 73 | 84 |
| 81 | 23 | 20 | 23 | 26 | 29 | 31 | 33 | 35 | 37 | 39 | 42 | 44 | 46 | 49 | 52 | 55 | 59 | 64 | 71 | 82 |
| 82 | 12 | 19 | 23 | 25 | 27 | 30 | 32 | 34 | 36 | 38 | 40 | 42 | 44 | 47 | 50 | 53 | 57 | 62 | 68 | 79 |
| 83 | 14 | 18 | 21 | 24 | 26 | 28 | 30 | 32 | 34 | 35 | 37 | 40 | 42 | 44 | 47 | 50 | 54 | 58 | 65 | 75 |
| 84 | 13 | 17 | 20 | 22 | 24 | 26 | 28 | 29 | 31 | 33 | 35 | 37 | 39 | 41 | 43 | 46 | 50 | 54 | 60 | 70 |
| 85+ | 55 | 15 | 18 | 20 | 22 | 24 | 25 | 27 | 28 | 30 | 31 | 33 | 35 | 37 | 40 | 42 | 45 | 49 | 55 | 65 |
Previous studies have reported that peak 30-min cadence is inversely-associated with BMI (Tudor-Locke, Brashear, et al., 2012), independent of the effects of age (Schuna et al., 2013). Given the prevalence of overweight and obese BMI’s in this nationally representative U.S. sample (Table 1), it is important to consider the effect of BMI on the peak 30-min cadence values provided herein. Notably, we observed a downward trend for peak 30-min cadence across age groups occurring simultaneously with a decrease in BMI. As such, the peak 30-min cadence values provided herein appear to be more strongly associated with advancing age.
Limitations
There are some limitations to this study that require mention. First, the rank-based quintile and centile values presented herein are subject to the unique characteristics of the sample and study procedures. As such, comparisons with other data sets should be made with some caution. Second, it is important to note that step measurement accuracy varies between physical activity monitors (Crouter, Schneider, Karabulut, & Bassett, 2003; Kooiman et al., 2015), consequently, data generated using alternative devices might yield varied results. Third, although previous studies have also examined peak 1-min cadence, defined as the single highest steps/min value recorded in a day (or average of monitored days) (Tudor-Locke, Brashear, et al., 2012), we chose to focus here only on peak 30-min cadence, as this metric reflects the persistence of behavior across a day, rather than a single spuriously high value. A 30-minute time frame also resonates with public health physical activity guidelines, which recommend that individuals accumulate at least 150 minutes of physical activity per week, which equates to approximately 30 minutes on most days of the week (Garber et al., 2011; World Health Organization, 2010). Finally, peak 30-min cadence is an indicator of “natural best effort” of ambulatory physical activity, and as such does not fully encompass all modalities and expressions of physical activity.
Conclusion
In summary, this analysis of the NHANES 2005–2006 PAM data provides normative (reference) values for peak-30 min cadence in older adults, an indicator of “natural best effort” for free-living ambulatory behavior. Given that walking is the primary exercise choice globally among adults (Hulteen et al., 2017) and a fundamental component of activities of daily living, these normative values represent an important contribution to the literature, serving as a point for comparison for accelerometer-determined free-living ambulatory behavior for older adults.
Acknowledgments
Funding
PTK, STB and WDJ are supported, in part, by 1U54 GM104940 from the National Institute of General Medical Sciences of the National Institutes of Health, which funds the Louisiana Clinical and Translational Science Center. EJA, JMS, TVB, EFM and CTL received no dedicated external funding support for this work.
Footnotes
Conflict of Interest
The authors have no conflicts of interest to declare.
References
- 2018 Physical Activity Guidelines Advisory Committee. (2018). 2018 Physical Activity Guidelines Advisory Committee scientific report. Retrieved from Washington, DC: [Google Scholar]
- Alberti KG, Eckel RH, Grundy SM, Zimmet PZ, Cleeman JI, Donato KA, … International Association for the Study of, O. (2009). Harmonizing the metabolic syndrome: a joint interim statement of the International Diabetes Federation Task Force on Epidemiology and Prevention; National Heart, Lung, and Blood Institute; American Heart Association; World Heart Federation; International Atherosclerosis Society; and International Association for the Study of Obesity. Circulation, 120(16), 1640–1645. doi: 10.1161/CIRCULATIONAHA.109.192644 [DOI] [PubMed] [Google Scholar]
- American Diabetes, A. (2018). 2. Classification and Diagnosis of Diabetes: Standards of Medical Care in Diabetes-2018. Diabetes Care, 41(Suppl 1), S13–S27. doi: 10.2337/dc18-S002 [DOI] [PubMed] [Google Scholar]
- Barreira TV, Katzmarzyk PT, Johnson WD, & Tudor-Locke C (2012). Cadence patterns and peak cadence in US children and adolescents: NHANES, 2005–2006. Medicine and Science in Sports and Exercise, 44(9), 1721–1727. doi: 10.1249/MSS.0b013e318254f2a3 [DOI] [PubMed] [Google Scholar]
- Barreira TV, Katzmarzyk PT, Johnson WD, & Tudor-Locke C (2013). Walking cadence and cardiovascular risk in children and adolescents: NHANES, 2005–2006. American Journal of Preventive Medicine, 45(6), e27–34. doi: 10.1016/j.amepre.2013.08.005 [DOI] [PubMed] [Google Scholar]
- Barreira TV, Schuna JM, Mire EF, Broyles ST, Katzmarzyk PT, Johnson WD, & Tudor-Locke C (2015). Normative steps/day and peak cadence values for United States children and adolescents: National Health and Nutrition Examination Survey 2005–2006. Journal of Pediatrics, 166(1), 139–143. doi: 10.1016/j.jpeds.2014.09.014 [DOI] [PubMed] [Google Scholar]
- Cole TJ (1990). The LMS method for constructing normalized growth standards. European Journal of Clinical Nutrition, 44(1), 45–60. [PubMed] [Google Scholar]
- Cole TJ, & Green PJ (1992). Smoothing reference centile curves: the LMS method and penalized likelihood. Statistics in Medicine, 11(10), 1305–1319. [DOI] [PubMed] [Google Scholar]
- Crouter SE, Schneider PL, Karabulut M, & Bassett DRJ (2003). Validity of 10 electronic pedometers for measuring steps, distance, and energy cost. Medicine and Science in Sports and Exercise, 35(8), 1455–1460. doi: 10.1249/01.MSS.0000078932.61440.A2 [DOI] [PubMed] [Google Scholar]
- Garber CE, Blissmer B, Deschenes MR, Franklin BA, Lamonte MJ, Lee IM, … Swain DP (2011). Quantity and quality of exercise for developing and maintaining cardiorespiratory, musculoskeletal, and neuromotor fitness in apparently healthy adults: Guidance for prescribing exercise. Medicine and Science in Sports and Exercise, 43(7), 1334–1359. doi: 10.1249/MSS.0b013e318213fefb [DOI] [PubMed] [Google Scholar]
- Gardner AW, Montgomery PS, Scott KJ, Afaq A, & Blevins SM (2007). Patterns of ambulatory activity in subjects with and without intermittent claudication. Journal of vascular surgery, 46(6), 1208–1214. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Gonzales JU, Shephard J, & Dubey N (2015). Steps per day, daily peak stepping cadence, and walking performance in older adults. Journal of Aging and Physical Activity, 23(3), 395–400. doi: 10.1123/japa.2014-0049 [DOI] [PubMed] [Google Scholar]
- Hulteen RM, Smith JJ, Morgan PJ, Barnett LM, Hallal PC, Colyvas K, & Lubans DR (2017). Global participation in sport and leisure-time physical activities: A systematic review and meta-analysis. Preventive Medicine, 95, 14–25. doi: 10.1016/j.ypmed.2016.11.027 [DOI] [PubMed] [Google Scholar]
- Kooiman TJM, Dontje ML, Sprenger SR, Krijnen WP, van der Schans CP, & de Groot M (2015). Reliability and validity of ten consumer activity trackers. BMC Sports Science, Medicine and Rehabilitation, 7(1), 1–11. doi: 10.1186/s13102-015-0018-5 [DOI] [PMC free article] [PubMed] [Google Scholar]
- Kuczmarski RJ, Ogden CL, Guo SS, Grummer-Strawn LM, Flegal KM, Mei Z, … Johnson CL (2002). 2000 CDC growth charts for the United States: methods and development. Vital Health Stat 11(246), 1–190. [PubMed] [Google Scholar]
- National Institutes of Health. (1998). Clinical Guidelines on the Identification, Evaluation, and Treatment of Overweight and Obesity in Adults--The Evidence Report. National Institutes of Health. Obesity Research, 6 Suppl 2, 51S–209S. [PubMed] [Google Scholar]
- Schuna JM Jr., Brouillette RM, Foil HC, Fontenot SL, Keller JN, & Tudor-Locke C (2013). Steps per day, peak cadence, body mass index, and age in community-dwelling older adults. Medicine and Science in Sports and Exercise, 45(5), 914–919. doi: 10.1249/MSS.0b013e31827e47ac [DOI] [PubMed] [Google Scholar]
- Troiano RP, Berrigan D, Dodd KW, Masse LC, Tilert T, & Mcdowell M (2008). Physical activity in the United States measured by accelerometer. Medicine and Science in Sports and Exercise, 40(1), 181–188. doi: 10.1249/mss.0b013e31815a51b3 [DOI] [PubMed] [Google Scholar]
- Tudor-Locke C, Brashear MM, Katzmarzyk PT, & Johnson WD (2012). Peak stepping cadence in free-living adults: 2005–2006 NHANES. Journal of Physical Activity and Health, 9(8), 1125–1129. [DOI] [PubMed] [Google Scholar]
- Tudor-Locke C, Camhi SM, & Troiano RP (2012). A catalog of rules, variables, and definitions applied to accelerometer data in the National Health and Nutrition Examination Survey, 2003–2006. Preventing Chronic Disease, 9, E113. doi: 10.5888/pcd9.110332 [DOI] [PMC free article] [PubMed] [Google Scholar]
- Tudor-Locke C, Johnson WD, & Katzmarzyk PT (2009). Accelerometer-determined steps per day in US adults. Medicine and Science in Sports and Exercise, 41(7), 1384–1391. doi: 10.1249/MSS.0b013e318199885c [DOI] [PubMed] [Google Scholar]
- Tudor-Locke C, & Rowe DA (2012). Using cadence to study free-living ambulatory behaviour. Sports Medicine, 42(5), 381–398. doi: 10.2165/11599170-000000000-00000 [DOI] [PubMed] [Google Scholar]
- Tudor-Locke C, Schuna JM Jr., Barreira TV, Mire EF, Broyles ST, Katzmarzyk PT, & Johnson WD (2013). Normative steps/day values for older adults: NHANES 2005–2006. The journals of gerontology. Series A, Biological sciences and medical sciences, 68(11), 1426–1432. doi: 10.1093/gerona/glt116 [DOI] [PubMed] [Google Scholar]
- U.S. Department of Health and Human Services. (2008). 2008 physical activity guidelines for Americans: Be active, healthy, and happy! Retrieved from www.health.gov/paguidelines
- Whelton PK, Carey RM, Aronow WS, Casey DE Jr., Collins KJ, Dennison Himmelfarb C, … Wright JT Jr. (2018). 2017 ACC/AHA/AAPA/ABC/ACPM/AGS/APhA/ASH/ASPC/NMA/PCNA Guideline for the Prevention, Detection, Evaluation, and Management of High Blood Pressure in Adults: A Report of the American College of Cardiology/American Heart Association Task Force on Clinical Practice Guidelines. J Am Coll Cardiol, 71(19), e127–e248. doi: 10.1016/j.jacc.2017.11.006 [DOI] [PubMed] [Google Scholar]
- World Health Organization. (2010). Global recommendations on physical activity for health. Retrieved from http://www.who.int/dietphysicalactivity/publications/9789241599979/en/ [PubMed]