Meeting Current Recommendations for Physical Activity ... cal activity (LTPA) in a national sample of ... meeting these new guidelines, with observed.
RESEARCH AND PRACTICE
Sociodemographic and Geographic Correlates of Meeting Current Recommendations for Physical Activity in Middle-Aged French Adults: the Supplémentation en Vitamines et Minéraux Antioxydants (SUVIMAX) Study | Sandrine Bertrais, PhD, Paul Preziosi, MD, Louise Mennen, PhD, Pilar Galan, MD, PhD, Serge Hercberg, MD, PhD, and Jean-Michel Oppert, MD, PhD
A low level of physical activity is recognized as a major risk factor for the development of several chronic diseases, including coronary heart disease, hypertension, obesity, type 2 diabetes, osteoporosis, and certain forms of cancer, as well as some mental health problems.1,2 Given the numerous benefits for health and well-being of regular physical activity, specific recommendations for the general population have been issued by US1–3 and European4,5 public health authorities and scientific expert panels. The 1990 American College of Sports Medicine (ACSM) guidelines, which focused on cardiorespiratory and muscular fitness, recommended vigorous exercise for at least 20 minutes performed 3 or more days per week.3 Recognition that moderate amounts of physical activity also confer substantial health benefits, especially for inactive or irregularly active subjects, led the Centers for Disease Control and Prevention (CDC) and the ACSM,2 as well as the US Surgeon General,1 to publish new recommendations focused on health-related physical activity. According to the 1995 CDC/ACSM guidelines, all adults should accumulate 30 minutes or more of moderate physical activity on most, and preferably all, days of the week.2 At present, a limited number of studies from the United States,6–8 Australia,9 and England10 have assessed the proportion of adults meeting these new guidelines, with observed rates varying from 25% to 50%. To our knowledge, no such studies have been conducted in populations from other European countries. Identifying the correlates (personal, social, and environmental) of participation in physical activity is a first step that may help to target at-risk populations and guide the development of preventive programs. Among the
Objective. We evaluated the characteristics of French subjects meeting current public health recommendations for physical activity. Methods. We assessed leisure-time physical activity cross-sectionally in 7404 adults aged 45 to 68 years with applied logistic regression models. Results. Meeting the recommended physical activity levels was more likely in subjects aged 60 years and older and in women with higher education levels or living in rural areas and was less likely in smokers. No association was found with time spent watching television. The contribution of vigorous activity to total time spent being active was approximately 2 times higher in subjects meeting recommendations. Conclusions. Participation in some vigorous activity may be viewed as a “facilitator” to attain physical activity recommendations. Relationships with physical environment variables in Europe need further investigation. (Am J Public Health. 2004;94:1560–1566)
many factors related to overall physical activity levels, associations with sociodemographic variables—such as age, gender, education, and income levels—are well documented.1,11,12 The most recent studies have focused on environmental factors, taking a broader “ecological” approach to understand the correlates of physical activity.12 The influence of the physical environment, which provides cues and opportunities for physical activity, is in particular a subject of growing interest.12,13 Urban/ rural status is 1 of the physical environment variables that can be easily obtained. Some studies have shown that rural US adults are less likely to meet the recommended levels of physical activity than their urban counterparts.14,15 However, other studies from the United States16,17 and England10 do not support these findings. Compared with the United States and other European countries, there are very few data regarding the habitual level of physical activity/inactivity in France.5 Therefore, the aims of the present study were to investigate individual and environmental factors, including the degree of urbanization of the place
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of residence, in relation to leisure-time physical activity (LTPA) in a national sample of middle-aged French adults and to compare physical activity patterns between the subjects who did and the subjects who did not meet the current public health recommendations (PHR).
METHODS Study Population Subjects were participants of the Supplémentation en Vitamines et Minéraux Antioxydants (SUVIMAX) study, an ongoing, randomized, double-blind, placebo-controlled, primary prevention trial designed to evaluate the impact of a daily antioxidant supplementation at nutritional doses on the incidence of ischemic heart disease and cancer.18 A total of 12 735 subjects (men, aged 45–60 years; women, aged 35–60 years), from all over France, were included in 1994–1995, with a planned follow-up of 8 years. All subjects gave their informed written consent to the study, which was approved by the ad hoc ethical committees (i.e., The Comité Consultatif
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de Protection des Personnes dans la Recherche Biomédicale and the Commission Nationale de l’Informatique et des Libertés). Details on recruitment, study design, and baseline characteristics of the subjects have been reported previously.18 For the present study, only those subjects with available data on LTPA in 1998, the year during which a detailed physical activity questionnaire was sent to the entire cohort, were included. So that a similar age range would be considered in both genders, the sample was further restricted to subjects aged 45 years or older in 1998. We also excluded subjects who had been confined to bed for more than 1 month during the period covered by the physical activity questionnaire. Analyses in the present report were thus based on data from 3404 men and 4000 women.
Assessment of Leisure-Time Physical Activity and Television Watching Physical activity and sedentary behavior were assessed using a French, self-administered version of the Modifiable Activity Questionnaire (MAQ).19 The MAQ was developed by Kriska et al.20 to investigate the relationships between physical activity and diabetes. The questionnaire assesses physical activity during both leisure time and work for the previous 12 months and uses time spent daily watching television as an indicator of sedentary behavior. The original version of the MAQ has been validated against energy expenditure measurements using the double-labeled water technique, and its test–retest properties have been demonstrated.21 The MAQ was initially designed to be interviewer-administered. Therefore, before the current study, we translated and adapted the questionnaire to fit selfadministration and French physical activity behavior. This self-administered French version of the MAQ was then compared with administration by trained interviewers in a subsample of the SUVIMAX cohort. The agreement between the 2 modes of administration was high, with intraclass correlation coefficients of more than 0.80.19 The questionnaire has been described in detail elsewhere.19,21 Briefly, for LTPA, subjects were asked to report all activities performed at least 10 times for 10 minutes per session during leisure time over the past 12
months. Then, detailed information was collected about the frequency and duration of each activity reported. Hours per week for all activities performed during the past year were summed to obtain an indicator expressed in hours per week of leisure activity. An energy expenditure indicator also was calculated by multiplying the number of hours per week of each leisure activity by its estimated metabolic cost. This score was expressed in metabolic equivalent task (MET)hours per week of leisure activity. A MET is the ratio of the working metabolic rate of an activity divided by the resting metabolic rate.22 One MET represents the metabolic rate of an individual at rest (sitting quietly) and is set at 3.5 mL of oxygen consumed per kilogram body mass per minute, or approximately 1 kcal/kg/h. A 10-MET activity would require 10 times the resting metabolic rate. METs for each activity were drawn from compendiums published by Ainsworth et al.22,23 Television watching was measured using a single question: “In general, how many hours per day do you spend watching television?” (hours/day). Based on the 1990 ACSM3 and the 1995 CDC/ACSM2 PHR for physical activity, we defined 4 groups of LTPA: (1) inactivity (no LTPA reported), (2) irregular activity (some LTPA but below level 3), (3) moderate activity (≥ 150 min/wk of LTPA > 3 METs but below level 4), and (4) vigorous activity (≥60 min/wk of LTPA >6 METs during ≥20 minutes per session). Subjects in groups 3 and 4 were considered to meet the current PHR. Four groups of television watching also were defined on the basis of the distribution of the time spent watching television in our sample (median, 2 h/d): less than 1 h/d, 1 to 2 h/d, 2 to 3 h/d, and ≥3 h/d.
Sociodemographic Variables, Smoking Status, and Geographic Data Level of education was obtained from a questionnaire at baseline and was coded in 3 categories according to the highest certification obtained (primary school, high school, and university or equivalent). Data on smoking status (current smokers, previous smokers, and nonsmokers) were collected through
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a specific questionnaire sent to the entire cohort in September 1998. The characteristics of the place of residence were based on the zip code of each subject as of January 1998. Four categories were defined according to the definition of the French National Institute of Statistics and Economic Studies (Institut National de la Statistique et des Etudes Economiques, Paris, France) on the basis of the economic activity of the area corresponding to each subject’s zip code, as follows24: (1) urban poles (urban units [1 or more municipalities] that offer at least 5000 jobs), (2) periurban zones (municipalities surrounding an urban pole), (3) multipolarized areas (municipalities located outside an urban unit, in which at least 40% of the resident population works in an urban area), and (4) rural municipalities (all other zip codes or municipalities).
Data Analyses Continuous variables are reported as means ± SD or medians (first quartile [Q1] and third quartile [Q3]). Cochran-MantelHaenszel statistics were used to examine the age-adjusted association between groups of LTPA and categories of television viewing. Logistic regression models were applied to assess factors related to meeting the physical activity recommendations. Multivariate models included age, educational level, smoking status, type of residential location, and group of television watching. Crude and multivariateadjusted odds ratios (with 95% confidence intervals) are reported. Analyses were stratified by gender. Data were compiled on an AlphaVMS system, and all statistical analyses were performed using SAS software version 6.12.25
RESULTS The mean age was 55.4 ±4.7 years in men and 53.2 ±5.3 years in women. In men and women, respectively, the mean LTPA duration was 4.8 ±5.6 h/wk and 3.8 ±4.4 h/wk, and the median LTPA score was 15.5 MET-h/wk (Q1=5.9 and Q3=31.4) and 11.0 MET-h/wk (Q1 = 3.7 and Q3 = 23.3). Recommended levels of physical activity were achieved by 62% of men and 52% of women, whereas 10% of men and 12% of women reported no physical
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TABLE 1—Characteristics of the SUVIMAX Study Population (n = 3404 Men and 4000 Women)
Age group, y 45–49 50–54 55–59 ≥ 60 Educational level Missing data Primary school High school University or equivalent Type of resident location Missing data Urban poles Periurban zones Multipolarized areas Rural municipalities Smoking status Missing data Nonsmoker Previous smoker Current smoker Time spent watching TV, h/d Missing data
