Overweight women who engage in 12 weeks of supervised aerobic exercise experience measurable decreases in waist size, total body weight, and body mass index.

Over 12 weeks, doing supervised aerobic exercise that burns 500 calories five times per week is linked to a decrease in body fat and an increase in lean body mass in women who are overweight, with an average BMI of 27.9.

In young women with a BMI between 25 and 27, participating in supervised group aerobic exercise three times a week for 12 weeks leads to measurable decreases in body weight, waist size, and body fat, along with an increase in muscle mass.

In overweight women, doing 12 weeks of supervised aerobic exercise does not lead to less movement during daily activities or more sitting, but it is linked to less total time spent sitting.

In middle-aged women, eight weeks of moderate aerobic exercise was linked to a decrease in muscle mass and fat-free mass, even though overall body weight and fat levels did not change, which may indicate limitations in how the measurements were taken or unmeasured factors like fluid balance or diet.

A 12-week supervised exercise program that burns about 10.5 megajoules per week leads to comparable decreases in body fat and fat mass in overweight and obese men and premenopausal women, with no meaningful difference between the sexes.