Long-term Effect Of Two Different Weight Loss Interventions On Changes In Body Composition And Performance.

During weight reduction, athletes are recommended a gradual weight loss of 0.5-1 kg·week-1 through moderate energy restriction. However, the effect of weight loss rate on long-term changes in body composition and performance has not been investigated in elite athletes. PURPOSE: To compare the loss of fat mass, LBM and performance 6 and 12 months after two different weight loss interventions promoting loss of 0.7% versus 1.4% of body weight per week in elite athletes. METHODS: 30 elite athletes from different sports were randomized to "slow reduction" (SR) or "fast reduction" (FR). 23 athletes completed 6 and 12 months posttest (SR, n=14, 23.5±3.3 yrs, 72.2±12.2 kg and FR, n=9, 21.4±4.0 y, 71.6±12.0kg) (mean±SD). The athletes had individualized diet plans promoting the predetermined weekly weight loss during intervention. Time in intervention was determined by the final weight goal. Four weekly resistance training sessions were added to the athlete's sport-specific training. All athletes were offered one nutritional counseling session within the month post intervention. BW, body composition (DEXA), 1RM tests, 40m sprint and vertical jump-tests were tested pre, post, 6 and 12 months post intervention. RESULTS: BW and fat mass decreased in both SR and FR (5.8±0.7% vs. 5.7±0.9% and 31±2.9 vs. 23±4.4%) during intervention. LBM increased by 2.0±1.3% in SR, but was not changed in FR (0.8±1.1%, p=0.2). Upper-body strength increased more in SR than in FR (12±2 vs. 6±2%, p<0.05), while the increase in squat strength was not significantly different between groups. Twelve months after intervention, BW had increased by 4.6±2.8% and 2.9±1.8%, and fat mass by 25±3.8 and 15.3±9.3%, in SR and FR respectively. LBM had decreased by 2.0±0.9% and 0.6±1.3% in SR and FR respectively, 12 months after intervention. There were no significant differences between groups after 12 months in body composition or performance. CONCLUSION: Although LBM increased in SR during intervention, there were no significant differences between groups after 12 months, suggesting that weight loss rate is not the most important factor for maintenance of body composition and performance after weight loss intervention. Hence, strength training and nutritional follow-up may be more important factors.