Pedometer Indices for Weekly Physical Activity Recommendations in Postmenopausal Women

Abstract

The aim of this study was to quantify pedometer-determined steps per day associated with 50, 100, and 150% of the current public health recommendation for weekly physical activity in sedentary postmenopausal women. A sample of 111 women from the DREW (Dose Response to Exercise in Women) study provided data. We randomly assigned women into one of three exercise groups expending 4, 8, or 12 kcal(-1).kg(-1).wk(-1) (KKW). Participants exercised alternately on a treadmill and recumbent cycle ergometer for a 6-month training period. Only treadmill sessions done with zero grade, at slow to moderate speeds (48-97 m.min(-1)) were used in this analysis. We controlled intensity at a HR equivalent to 50% of VO(2peak). Participants wore pedometers at baseline and throughout the study to assess their free-living physical activity (steps.d(-1)) Baseline averages were <5400 steps.d(-1) for the 4-, 8-, and 12-KKW groups. During 6 months of exercise training, free-living step counts remained <5400 steps.d(-1) and did not significantly differ from baseline for each group. Average speeds and distances per exercise session were 2.7 +/- 0.4 mph, 1.2 +/- 0.2 miles (4 KKW), 2.6 +/- 0.4 mph, 2.2 +/- 0.4 miles (8 KKW), and 2.8 +/- 0.3 mph, 2.7 +/- 0.4 miles (12 KKW). This yielded 2771 (4 KKW), 5457 (8 KKW), and 6534 (12 KKW) steps per exercise session 3-4 d.wk(-1). Initially sedentary postmenopausal women can meet 50% (4 KKW), 100% (8 KKW), and 150% (12 KKW) of the current public health recommendation of weekly physical activity through planned moderate-intensity walking, accumulating an average of about 2800 (50%), 5500 (100%), and 6500 steps.d(-1) (150%) 3-4 d.wk(-1).