Sedentary behaviors, physical activity, and metabolic syndrome in middle-aged French subjects

To study the relationships of time spent in sedentary occupations with the National Cholesterol Education Program-defined metabolic syndrome (MS), taking into account the habitual level of physical activity (PA).

This was a cross-sectional analysis in 1902 men and 1932 women 50 to 69 years of age participating in the French Supplementation with Antioxidant Vitamins and Minerals study. We assessed past-year PA, television watching or computer use, and reading during leisure with the Modifiable Activity Questionnaire. Subjects who performed at least 150 min/wk of moderate-intensity PA (3 to 6 metabolic equivalent tasks) or 60 min/wk of vigorous PA (>6 metabolic equivalent tasks) were considered as meeting recommended levels.

The frequency of most MS components increased with time spent in front of a screen and decreased with increasing PA levels. The likelihood to have MS, adjusted for age, education, and smoking, was decreased by one-third in subjects meeting moderate PA guidelines and by two-thirds in subjects meeting vigorous PA recommendations [odds ratio (95% CI), 0.34 (0.17 to 0.66) in women, 0.44 (0.28 to 0.68) in men] compared with those with insufficient PA. Independently of PA levels, time spent in front of a screen was positively associated with the likelihood to have the MS in women [odds ratio (95% CI), 3.30 (2.04 to 5.34)], whereas in both sexes, no association was found with time spent reading.

The relationship of the MS with a sedentary lifestyle differs according to sex and type of sedentary occupation. These results suggest the need to assess selected indicators of sedentary behavior in preventive programs.