The effect of increasing physical activity on health benefits in sedentary women
The purpose of this study was to evaluate whether the current CDC/ACSM physical activity recommendation, ("30 minutes or more of accumulated moderate-intensity activity, most if not all, days of the week") would improve women's health through a reduction ofcoronary heart disease (CHD) risk factors. Twenty-one sedentary females (ages 49 ± 7 yrs.) with one or more CHD risk factors underwent baseline laboratory including: resting heart rate and blood pressure, resting electrocardiogram, body mass index, bioelectrical impedance, skinfold measures, waist-to-hip, blood lipid profile, and V02max. The VO2 was determined by an exercise treadmill test using the Ball State University Ramp protocol. The subjects were instructed on the CDC/ACSM recommendation, the physical activity survey, and given examples of moderate-intensity activity. The survey data was collected bimonthly over the six month period. The subjects reported participating in >_ 30 min. of moderate-intensity activity an average of 4 f 1 days/week with an average duration of 54 ± 26 min. On the remaining days, the subjects reported doing an average of 14 ± 6 minutes per day. Also, 90% of the women reported doing the activity in continuous bouts. Following the six month study period, the women were retested in the laboratory. Sixteen subjects completed the post-testing. The results of the sixteen women showed a significant improvements in HDL-cholesterol (51 ± 15 vs.56 ± 15 mmHg; p=<.05) and TC/HDL ratio (4.5 ± 1 vs.4.25 ± 1.3; p=<.05). There were no significant changes in the other risk factor variables examined or their V02,„.. It was concluded that the majority of previously sedentary, middle aged women can not meet the CDC/ACSM recommendations for daily activity and total energy expenditure. Additionally, it appears that when given the choice, these women choose to do activity in continuous time blocks versus breaking the daily activities into shorter time periods.