Metabolic and anthropometric changes with weight cycling in wrestlers.

Repeated cycles of weight loss and regain have come to be known as weight cycling. This phenomenon is frequently observed in athletes who must meet specific weight categories to qualify for competition. The purpose of this study was to determine the metabolic and anthropometric changes that occur with rapid weight loss/regain cycles in competitive wrestlers. Collegiate wrestlers were divided into two groups, "cyclers" (N = 8) and "noncyclers" (N = 6), based on their reported dieting history. Measurements included a 3-d diet record, resting energy expenditure (REE), skinfold and girth measures, and biochemical tests at three time points: preseason, peak season, and off-season. All anthropometric measures changed with time, and a diet group by time interaction was observed for the trunk to extremity skinfolds ratio (T/E) (P < 0.05), with greater fat loss and regain from the trunk area of the cyclers. There were no differences in REE within or between groups. Serum triiodothyronine (T3) values decreased over time (P < 0.01). Large weight losses appear to have occurred due to both dieting and short-term dehydration, and although physiological changes were observed, a training effect may have overridden any metabolic influence of weight cycling.