ABSTRACT
There exists considerable controversy regarding the impact of different modes of exercise training on total daily energy expenditure (TEE). To examine this question, young, nonobese women were randomly assigned to a supervised 6-month program of endurance training, resistance training, or control condition. TEE was measured before and 10 d after a 6-month exercise program was completed with doubly labeled water. Body composition was determined from dual energy x-ray absorptiometry, maximum aerobic capacity from a treadmill test to exhaustion, and muscular strength from one-repetition maximum tests. Results showed that body composition did not change in endurance-trained women, but maximum aerobic capacity increased by 18%. Resistance-trained women increased muscular strength and fat-free mass (1.3 kg). TEE did not significantly change when measured subsequent to the endurance or resistance training programs. Absolute resting metabolic rate increased in resistance-trained women but not when adjusted for fat-free mass. No change in physical activity energy expenditure was found in any of the groups. These results suggest that endurance and resistance training does not chronically alter TEE in free-living young women. Thus, the energy-enhancing benefits of exercise training are primarily derived from the direct energy cost of exercise and not from a chronic elevation in daily energy expenditure in young, nonobese women.
