Reductions in total body fat and other adiposity outcomes in postmenopausal women were observed to be greater in those who exercised moderately to vigorously 300 minutes per week compared to 150 minutes per week, according to an article published online in the journal JAMA Oncology.
Participants in the study included 400 previously inactive, postmenopausal women who were disease-free, nonsmokers, and nonusers of exogenous hormones with a body mass index 22 to 40.
Two cohorts of participants were established: group one completed 30 minutes of moderate-volume activity per session and group two completed 60 minutes of high volume activity per session. Both groups participated in 5 days of aerobic exercise per week with 3 days supervised and 2 days unsupervised, and were asked to not change their usual diet.
Results showed 384 out of the 400 women provided adiposity measurements at baseline and follow-up. The high-volume group had a median adherence at full prescription of 254 women (166-290) compared to the moderate-volume group with a median adherence of 137 (11-150).
The high-volume group’s mean reduction in total body fat was significantly greater than the moderate-volume cohort (least-squares mean difference, −1.0%; 95% CI: −1.6%, −0.4%; P=0.002). Similarly, the subcutaneous abdominal fat and waist to hip ratio decreased significantly more in the high-volume group (least-squares mean difference, −10.8; 95% CI: −19.5, −2.2 cm2; P=0.01) compared to the moderate-volume group (−0.01; 95% CI: −0.02, 0.00: P=0.04).
The two groups did not have a reported difference between changes in weight and intra-abdominal fat (least-squares mean difference, −0.7, 95% CI: −1.6, 0.2 kg; P=0.11, and −1.5; 95% CI: −5.9, 2.9 cm2; P=0.50, respectively).
Body fat increases postmenopausal breast cancer risk. Physical activity may decrease risk through adiposity changes, but the optimal dose of activity is unknown. Objective To compare the effects of 300 vs 150 min/wk of moderate to vigorous aerobic exercise on body fat in postmenopausal women.