Leisure and occupational physical activity in relation to body mass index in men and women

Abstract

Background: When studying physical activity in relation to health it is important to use valid methods. Objective : To test the relative validity of a short physical activity questionnaire against 3 day physical activity records, and to describe leisure and occupational physical activity in men and women by body mass index(BMI).Design: The validation study included 133 men and 139 women, and the cross-sectional study 1380 men and 2281 women. All subjects were aged 37-60 years, with a BMI of 17.6-59.2 kg m-2. Results: Mean estimated physical activity level (PAL) from the 3 day activity records differed by reported grade of occupational physical activity from the short activity questionnaire (p<0.01 in both genders).Among men PAL values increased with increasing activity grade. The same pattern, although weaker, was seen for women. Estimated PAL values did not differ significantly by reported grade of leisure-time physical activity. Gender differences were noted in the 3 day activity records. Men recorded more sitting than women, whereas women were more engaged in walking and light activities. In the cross-sectional analysis physical activity, both in leisure time and at work, decreased with increasing degree of overweight and obesity among both men and women. Conclusions: Mean PAL values increased with increasing grade of occupational physical activity reported in a short physical activity questionnaire. Although PAL values were not related to reported leisure-time physical activity, high BMI was associated with less physical activity both during leisure time and at work in a large group of men and women with varying BMI. Keywords: activity record; gender difference; obesity; PAL; questionnaire