Cardiorespiratory effects of weight reduction by exercise in middle-aged women with obesity.

The cardiorespiratory responses to weight reduction due to physical exercise were examined in fourteen women with obesity, aged 36 to 67 years (Body Mass Index, 32.4 +/- 1.5 kg/m2). The patients were instructed to exercise at approximately 60% of maximum oxygen uptake for 2 h every day for approximately 3 months. To evaluate physical strength, a graded cycling exercise test was performed both before and after the exercise period, monitoring gas exchange, ventilation, and heart rate. After the exercise period the body mass index and percentage fat both decreased by 11% and 18%, respectively (P < 0.001), although lean body mass did not change; maximum oxygen uptake and maximum heart rate did not change significantly, but peak ventilation equivalent, maximum metabolic equivalent and maximum load increased by 12%, 14% and 11%, respectively (P < 0.05, P < 0.001 and P < 0.001, respectively). Maximum oxygen uptake per unit body weight increased by 5% (P < 0.001). These results suggest that weight reduction as a result of exercise improves cardiorespiratory function in middle-aged women with obesity.