Comparison of Physical Activity Levels in Physicians and Medical Students With the General Adult Population of the United States

Abstract

Objective:

Physicians who are physically fit have a higher likelihood of counseling their patients about physical activity. We sought to determine if the amount of physical activity in physicians and medical students differs from the general adult population of the United States and if geographic differences in physical activity levels exist.

Methods:

A cross-sectional survey was distributed to physicians and medical students throughout the United States to determine their level of physical activity according to US Department of Health and Human Services (DHHS) 2008 guidelines; data were collected from participants from June 2009 through January 2010. Our data set was compared with physical activity data from the Centers for Disease Control and Prevention (CDC) and we used geographic regions defined by the US Census Bureau.

Results:

Our survey respondents contained 631 attending physicians, 159 fellow physicians, 897 resident physicians, and 262 medical students. Only 64.5% of the general US adult population meets DHHS guidelines for physical activity, but 78% of the survey participants fulfilled the guidelines. The percentage of US adults who do not engage in leisure-time physical activity is 25.4% compared with 5.8% of survey participants. Survey respondents in the southern region had the lowest physical activity levels and participants in the western region had the highest levels.

Conclusion:

Physicians and medical students engage in more physical activity than the general US adult population. Regional differences in the general population’s physical activity also persisted in physicians and medical students. Therefore, physicians who complete less physical activity may be less likely to encourage patients to engage in physical activity in geographic areas where the adult population is less active.

Introduction

Although there are limited data available on the physical activity patterns of physicians and medical students, some studies indicate that the physical activity level of physicians can be directly correlated with physician-patient counseling patterns that encourage more active behavior.^1-4 The importance of physical activity has been studied extensively, yet many physicians fail to assess physical activity in their patients.^5,6 When health care providers provide patients with physical activity counseling, they increase the likelihood that their patients will be physically active.^7,8 Efforts should be made to encourage physical activity in patients because they have a positive impact on health-related quality of life.⁹

Regular physical activity plays a role in improving the health of the adult and pediatric population. In 2008, the US Department of Health and Human Services (DHHS) released its first national guidelines for physical activity¹⁰; Healthy People 2020 identified physical activity as one of the leading health indicators to decrease the risk of chronic diseases such as type 2 diabetes mellitus, hypertension, and coronary artery disease.¹¹

The physical activity guidelines of the DHHS are reflected in the 2010 State Indicator Report on Physical Activity, which was released by the US Centers for Disease Control and Prevention (CDC). The report was created in an effort to increase physical activity levels in all Americans, as stated below:

National and state-specific information is reported in the State Indicator Report on Physical Activity, 2010, for behavioral, policy, and environmental indicators. The behavioral indicators are derived from physical activity recommendations outlined in Healthy People 2010 objectives, the nation’s initial framework for health priorities and the 2008 Physical Activity Guidelines, a science-based guide on the types and amounts of physical activity that provide substantial health benefits for Americans.^10,12

The report supports key strategies in public health, such as creating or enhancing access to places for physical activity, enhancing physical education and activity in schools and child care settings, and supporting urban design, land use, and transportation policies.¹³

In our initial study, we sought to determine the physical activity level in a representative sample of US physicians and medical students.¹⁴ Our sample of participants had a higher likelihood of being physically active than the general adult population. The purpose of our current study is to determine if the geographic differences that exist in the United States among the general adult population persist in the physician and medical student population. We hypothesize that geographic differences do persist in physicians and medical students and propose these differences might contribute to regional physical activity trends.

Materials and Methods

Participants and Data Collection

We created an online exercise survey to study a total of 2100 participants (700 attending physicians, 700 resident and fellow physicians, and 700 medical students). Participants in each group completed a 3 to 4 minute online survey that assessed their level of physical activity. Initially, we advertised the survey through the American Medical Association online newsletter in order to gather an adequate sample from each of the individual groups being studied. We also distributed fliers at the American Medical Association Annual Meeting, which was held in June 2009. The yield of completed surveys from our first effort was approximately 450.

In order to increase the sample size of the study, we gathered survey responses from additional sources. We sent individual emails to designated institutional officials for all residency and fellowship programs in the United States using the American College of Graduate Medical Education website. We also sent individual emails advertising the survey to the leaders of the Aerospace Medical Association, American Academy of Pediatrics, American College of Physicians, and the American Association of Public Health Physicians. Many individuals who received the survey forwarded the survey to their colleagues throughout the country. The period of data collection resulting from our second effort to circulate the survey was approximately 8 months (June 2009–January 2010). Because the survey was distributed through numerous sources, there was no way to formally document the number of actual survey recipients. The study was considered exempt by the institutional review board of Palmetto Health Richland Hospital and there were no incentives for participation in the study.

Survey Instrument

We developed an anonymous cross-sectional survey to obtain self-reported information from physicians and medical students about their overall health and background, medical training and specialty, practice setting, physical activity level, and confidence in providing physical activity counseling. We also used the short form of the International Physical Activity Questionnaire (IPAQ) to quantify the level of physical activity of the participants. Each survey was concise enough to allow all participants to complete the survey in approximately 3 minutes.

The IPAQ has undergone rigorous testing in numerous countries and this research indicates that it is a valid and reliable questionnaire for assessing participant physical activity and inactivity.^15-17 We chose the short form of the IPAQ to encourage participants to complete the survey in its entirety. The short version of the IPAQ asks participants to recall their physical activity for the past 7 days and has been indicated for national monitoring, whereas the long form is useful for more detailed assessments.

In addition to the short form of the IPAQ, our survey asked participants for information that included: age, gender, ethnic background, weight, height, marital status, number of children in the household, stage of training (medical student, resident physician, fellow physician, or attending physician), specialty of training, type of practice (academic, hospital based, non-clinical, private practice, retired), state (location of practice or medical school), setting (urban, rural, suburban), average number of hours worked per week, frequency of providing physical activity counseling, confidence regarding physical activity counseling, and belief in the adequacy of personal physical activity level.

Statistical Data Analysis

Survey data were collected on Survey Monkey and were downloaded into a Microsoft Excel spreadsheet; survey responses were then converted into variables for analysis using the R statistical program. The participant responses for number of hours and days per week for vigorous, moderate, and walking exercise were used to create a dichotomous variable, which indicated whether or not the DHHS guidelines were met and was the primary participant outcome for the study. Descriptive tables and graphics were also developed for the data. Some levels of categorical predictor variables were collapsed because the data collected were too sparse to analyze. Seventy-seven observations had missing values for one or more predictor variables.

We compared our data set with the CDC’s 2010 State Indicator Report on Physical Activity¹³ and sorted the survey participants by state to determine what percentage of participants fit into the 3 levels of physical activity: active, highly active, or engaged in no leisure-time physical activity. Because we obtained raw data from the CDC report,¹⁰ we were unable to validate the differences in the measures reported from the IPAQ portion of our physician survey. We grouped the state data from our surveys and the CDC report into the geographic regions defined by the US Census Bureau, which categorizes the United States into 4 official regions and 9 divisions.¹⁸ In order to increase simplicity, we defined our results according to the 4 US Census Bureau regions: Northeastern, Midwestern, Western, and Southern regions. Although it is possible to calculate sampling weights based on the known state and regional demographics for the types of medical clinicians we studied, we are not reporting such adjustments because of the non-probability nature of the sample. Physical activity indicators for the US population by region included the state weights for the proportion of adults who were highly active or active and the proportion of adults who engaged in no leisure-time physical activity. The proportions were computed using the Physical Activity Module, the 2007 Behavioral Risk Factor Surveillance System, and the 2008 Behavioral Risk Factor Surveillance System.^19,20

Results

Survey Respondent Demographics

There were a total of 1949 respondents to the survey and each of the 4 levels of medical training/practice were represented: medical student, resident physician, fellow physician, and attending physician. Of the total population surveyed, 897 (46%) participants were resident physicians, which was the largest group represented in the survey. Women responded to the survey slightly more than men; a total of 1026 (52.6%) participants were women. The sex distribution in our study is similar to the sex distribution of the CDC’s 2010 State Indicator Report on Physical Activity.¹⁰ The distribution of the respondents by the number of hours worked per week was fairly symmetrical; however, slightly more respondents reported working ≥ 60 hours per week. Survey participants who indicated that they worked between 60 and 69 hours per week numbered 453 (25.2%; Table 1). Although the study participants represented a wide ethnic variation, 1368 (70.2%) participants were Caucasian. The ages of participants ranged from 20 to 79 years; the age range represented most by participants was 20 to 29 years (37.9%; Table 1).

Table 1.

Study Participant Demographics

Study Participant Demographics
Age, years	Number	Percentagea
20–29	738	37.9%
30–39	691	35.5%
40–49	227	11.7%
50–59	202	10.4%
60–79	90	4.6%
Race	Number	Percentagea
Caucasian	1368	72.3%
Asian	283	15.0%
African American	96	5.1%
Other	145	7.7%
Hours Worked Per Week	Number	Percentagea
< 40	103	5.3%
40–49	320	16.4%
50–59	433	22.2%
60–69	453	23.2%
70–79	440	22.6%
> 80	200	10.3%
Level of Training	Number	Percentagea
Attending	631	32.4%
Fellow	159	8.2%
Med Student	262	13.4%
Resident	897	46.0%

^aValues are expressed as percentages of the entire study population.

Study participants represented a wide variety of medical subspecialties; 338 (17.3%) of respondents were internal medicine specialists, which was the largest single subspecialty group. However, other primary care subspecialties also had significant numbers of respondents, such as pediatrics and family medicine, which had 295 (15.1%) and 220 (11.3%) responses, respectively. Other subspecialties represented in the survey included 408 respondents and consisted of: aerospace medicine, allergy and immunology, colon and rectal surgery, dermatology, general preventive medicine, medical genetics, neurological surgery, neurology, nuclear medicine, occupational medicine, ophthalmology, otolaryngology, pathology, physical medicine and rehabilitation, plastic surgery, public health, radiation oncology, radiology-diagnostic, thoracic surgery, urology, and vascular surgery. There were also many combined subspecialties, such as internal medicine/pediatrics.

Survey participants were from 48 states, Washington, DC, Puerto Rico, and the Federated States of Micronesia. Areas with > 100 respondents included Michigan, South Carolina, Massachusetts, New York, Maryland, Texas, California, and Washington, DC. Participants were categorized into 1 of the 4 US regions by level of training (Figure 1).

Figure 1.

Regional Distribution of Survey Participants by Level of Medical Training.

Survey Respondents and DHHS Guidelines

Our primary aim was to establish the percentage of medical students, resident and fellow physicians, and attending physicians who meet the current DHHS guidelines by state and region. We then compared that percentage with the physical activity level of the general US adult population as determined by the CDC State Indicator Report on Physical Activity. We based our assessment of physical activity on 3 levels: highly active adults, active adults, and adults who participate in no leisure-time physical activity.

Current DHHS guidelines indicate that adults should get ≥ 150 minutes of moderate-intensity aerobic activity, ≥ 75 minutes of vigorous-intensity aerobic activity, or a combination of activity intensities (1 minute vigorous intensity = 2 minutes of moderate intensity) to experience substantial health benefits, which include lower risk for premature mortality, coronary heart disease, stroke, hypertension, type 2 diabetes mellitus, and depression. For increased and additional health benefits, such as lower risk for colon and breast cancer and prevention of unhealthy weight gain, adults should participate weekly in ≥ 300 minutes of moderate-intensity activity, ≥ 150 minutes of vigorous-intensity activity, or an equivalent combination.^10,21

Regarding the 3 physical activity levels, 64.5% of the general US adult population was physically active, whereas 78% of respondents to our survey were physically active. Highly active adults who met DHHS guidelines made up 43.5% of the general US adult population compared with the 49.3% of survey respondents who were highly active. Only 5.8% of respondents to our survey did not engage in leisure-time physical activity, whereas 25.4% of the general adult US population did not engage in leisure-time physical activity (Figure 2).

Figure 2.

Comparison of Physical Activity of US Adults Versus Survey Participants.

When we imposed regional categories upon our study participants and the general US adult population, adults in both groups who resided in the Western region of the United States had the highest likelihood of being physically active. The percentages of physically active US adult and survey respondents were 67.8% and 79.1%, respectively (Table 2). United States adults (46.5%) and survey participants (55.3%) that met DHHS guidelines for being highly physically active were also most likely to reside in the Western region of the US. The Southern region had the lowest rates of physical activity, with 26.8% of the general US adult population and 6.4% of the survey participants not engaging in any leisure-time physical activity.

Table 2.

Regional Physical Activity in US Adults Versus Survey Participants

Region	Physically Activea		Highly Activea		No Leisure-Time Physical Activitya
	US Adults	Physicians	US Adults	Physicians	US Adults	Physicians
Midwest	65.2	77.2	43.7	46.8	25.3	4.8
Northeast	65.4	78.8	44.4	48.8	24.9	5.8
South	62.4	77.6	41.7	48.6	26.8	6.4
West	67.8	79.1	46.5	55.3	22.4	5.5

^aAll values are presented in percentages. The highest value in each column is noted in boldface type.

Discussion

Our cross-sectional online survey demonstrates that physicians and medical students engage in more physical activity than the general US adult population¹⁴; the physical activity level of survey participants mirrors the physical activity trend in their geographic region. However, other studies propose that physicians are less likely to be physically active than the general population due to schedule demands associated with their careers.^1,22 Although physicians tend to support preventive measures like physical activity, factors such as lack of training, negative attitudes towards patient activity counseling, and the negative influence of the physician’s personal health behavior play a role in keeping physicians from encouraging their patients to engage in healthy activity behaviors.^6,23 In a recent study, Smith et al²⁴ indicated that < 50% of primary care providers offer diet, physical, activity, or weight control guidance to patients.

Other studies sought to ascertain environmental determinants of physical activity in adult and pediatric populations.^25-28 Wendel-Vos et al²⁵ determined that social support and having a physical activity companion were convincingly associated with the likelihood a patient would participate in physical activity. Many studies conducted about physical activity determinants in the pediatric population conclude that factors such as gender, race, socioeconomic status, and peer groups play a role in the physical activity levels of patients.^26-28 These studies may illuminate why our survey results support the notion that physicians and medical students exhibit higher levels of physical activity compared with the general US adult population.

The key findings of our study indicate that residents of the west are the most active in both the general US adult population and survey respondents (Table 2). The rate of physically active western residents is 67.8% and 79.1% for US adults and survey participants, respectively; the percentages of highly physically active Western US adults and survey respondents were 46.5% and 55.3%, respectively. Even more profound results were noted in a study conducted by Livadauis et al²⁹ on lifestyle behavior counseling for women patients of California physicians; the study assessed physician physical activity and physical activity counseling by physicians. Of the 822 survey respondents in the study, 9.9% of participants reported being sedentary, 36.0% of participants were moderately active, 27.7% of respondents were active, and 26.4% of participants reported being very active. Additionally, 56.1% of the physicians in the study reported counseling ≥ 75% of their patients about being physically active; these results support the theory that physicians residing in the western region of the United States are highly physically active and that they encourage physical activity in their patients.

Abramson et al³⁰ presented data that suggest inadequate time and knowledge are key reasons why physicians do not counsel patients about physical activity. Although our study did not investigate these criteria, factors like inadequate time and knowledge about physical activity may account for the geographic differences in physical activity that we noted. Reasons for the lack of physical activity aside, there appears to be a recent increase in the rates of physical activity counseling offered by physicians. In a recent NCHS data brief, Barnes and Schoenbern³¹ evaluated trends in the United States regarding physician and health care professional counseling regarding patient physical activity. Their results indicate that 32.4% of adults who had seen a physician or other health professional in 2010 had been advised to engage in physical activity; this was a 40% increase from 2000, in which only 22.4% of adults received physical activity counseling from a physician.

Our study had several strengths. First, our survey respondents represented a diverse demographic group in terms of age, gender, ethnicity, subspecialty, and level of training. Second, our study used the well-established IPAQ to assess physical activity levels in participants. Third, to our knowledge, this is the largest study addressing the physical activity levels of resident and fellow physicians. Fourth, no current studies address the physical activity level of our study population as it relates to existing DHHS guidelines, the CDC State Indicator Report on Physical Activity, or geographic regions of the United States.

There are several weaknesses contained in our study. First, although we obtained a diverse sample of study participants, we were unable to determine the survey response rate because we had no mechanism to monitor the number of persons who accessed the survey without completely finishing it. We also cannot be sure that this non-probability sample is representative of all US physicians. Second, some physical activity levels were likely misclassified because the survey involved self-reported data. There is also a strong likelihood that survey respondents represent a group with a higher base-line physical activity level than individuals who chose not to respond to the survey. Third, although several states had a very strong representation in the study population, many states had very low numbers of respondents. Fourth, we did not assess participant familiarity with the current DHHS recommendations for physical activity. Finally, it is difficult to determine if the IPAQ-derived survey instrument that we used to assess physical activity in respondents is similar to the CDC instrument used to evaluate the physical activity of the general US adult population.

Conclusion

Although physicians and medical students understand the positive effects of preventive measures on overall patient health, such as physical activity, the physical activity level of this population could be improved. As physicians and medical students make efforts to improve their activity levels, they will exert a positive influence on the lives of their patients. Regional differences in physical activity levels that exist in the general US adult population persist in attending physicians, resident and fellow physicians, and medical students. The physical activity levels of physicians and medical students in particular states or regions may be another factor that contributes to geographic differences in the activity levels of the general US adult population; physicians who are more physically active are more likely to encourage physical activity in their patients.