INFLUENCE OF WALKING VOLUME ON HEALTH BENEFITS IN WOMEN POSTMENOPAUSE

The health benefits of physical activity are believed to be related mo re to exercise volume than to intensity. In this 24-wk study, we exami ned the effect of walking volume on aerobic fitness, serum lipids, and body composition in women post-menopause, a population at risk for co ronary artery disease. Of 79 women randomly assigned to groups at the outset, 56 completed the study (mean age 61.3 +/- 5.8). Participants w alked at an intensity of 60% peak oxygen uptake (VO2peak) for 60 min, 3 d . wk(-1) (N = 19) or 5 d . wk(-1) (N = 17), or remained sedentary (N = 20). Walking 3 or 5 d . wk(-1) increased VO2peak (ml . kg(-1). mi n(-1)) by 12% and 14%, respectively (P < 0.01). There were no changes in serum lipids in response to either program. Percent body fat decrea sed by 1.1% and 1.3% in those walking 3 and 5 d . wk(-1), respectively ; both changes significantly different from the control group (P < 0.0 5). Walking 5 d . wk(-1) did not result in more health benefits than 3 d . wk(-1), possibly due to a greater compensatory decline in activit ies other than the walking program, or greater discrepancies between a ctual and reported activity and food intake. Longer-duration programs, or simultaneous changes in diet, may be necessary to alter serum lipi ds in nonobese, normo-lipidemic women post-menopause.