The effects of long-term, moderate intensity, intermittent exercise on aerobic capacity, body composition, blood lipids, insulin and glucose in overweight females

Objective: To test the hypotheses that the accumulation of 30 min of moderate intensity, intermittent exercise, 5 d/week^-1, for 32 weeks, will increase aerobic capacity, alter body composition and improve blood lipids, insulin and glucose. Secondly, to identify individuals who may respond to moderate intensity, intermittent exercise. Subjects: Thirteen sedentary, moderately obese females, aged 43 ± 11 (y), body mass index (BMI) 32.7 ± 7.7 (kg/M²), body fat 40.6 ± 8.8 (%), VO₂max 24.0 ± 4.6 (ml/kg^-1/min^-1). Measurements: Aerobic capacity, body composition, blood lipids, fasting insulin and glucose, energy intake. Results: Group data showed no significant changes for aerobic capacity, body composition, blood lipids, insulin or glucose. However, 7 of the 13 subjects increased aerobic capacity, lost fat weight and improved insulin. Adherence to the exercise regimen was excellent with 82.6 ± 10.0% of the prescribed exercise completed. Conclusions: Moderate intensity, intermittent exercise for a total of 30 min, 5 d/week^-1, for 32 weeks duration, was not a sufficient stimulus to significantly increase aerobic capacity, alter weight, body composition or improve blood lipids, insulin or glucose for the entire group. However, those subjects who increased aerobic capacity and decreased fat weight were significantly older, had lower maximal aerobic capacity and greater body fat at baseline compared to the six subjects who did not increase aerobic capacity and decrease fat weight. For both groups, moderate intensity, intermittent exercise showed excellent adherence and this may be a useful model for future research studies.