Weimann, Edda. Gender-related differences in elite gymnasts: the female athlete triad. J Appl Physiol 92: 2146-2152, 2002; 10.1152/japplphysiol.00572.2001.-High-intensity training can alter the normal pattern of pubertal development in elite gymnasts. We investigated sex hormones, the ob gene product leptin, body composition, nutrition, and eating habits in female and male elite gymnasts from national cadres to elucidate gender-related differences. Serum leptin levels were decreased, particularly in pubertal girls, and did not show the normal developmental pattern. After leptin levels were transformed into standard deviation scores, mainly pubertal female gymnasts had significantly lower values than normal controls of the same gender, pubertal stage, and body mass index. The percentage of body fat was reduced compared with a normal age-matched population in both genders but to a higher degree in female gymnasts. When leptin standard deviation scores were based on percent body fat instead of body mass index, mean values were still significantly decreased compared with those of normal controls: Ϫ1.05 in girls (P Ͻ 0.001) and Ϫ0.60 in boys (P ϭ 0.025). In both genders, total energy consumption and nutritional intake were insufficient, although to a lesser extent in male gymnasts. Pubertal development is influenced to a different degree in female and male elite gymnasts. In contrast to their male counterparts, high-intensity training takes place during the sensitive phase of pubertal maturation in female gymnasts. Whereas the girls displayed low estrogen levels, hypoleptinemia, reduced body fat mass, insufficient caloric intake, and retarded menarche, the pubertal development of male gymnasts remained almost unaltered. puberty; gymnastics; leptin; body composition HIGH-INTENSITY TRAINING DISPLAYS gender-related differences in athletes. In addition, the influence of endurance training on pubertal and physical development varies greatly, depending on the nature of sports. Mild hyperandrogenism can occur in female world-class swimmers (47), whereas highly trained female longdistance runners tend to develop cycle abnormalities (8). In male long-distance runners, testosterone levels, libido, and reproductive function are decreased (13,29). When growth development of female gymnasts and swimmers is compared, gymnasts present lower growth velocity and a marked stunting of leg-length growth, and they fail to reach full familial height (43).Even metabolism differs between female and male top athletes. Because of higher estrogen concentrations, the oxidation of amino acids and carbohydrate is lower during endurance training in girls, whereas there is a higher proportion of lipid oxidation (41). In ultra-endurance exercise, such as the Ironman triathlon, estradiol (EE) was 58% increased and testosterone was 58% decreased in men postrace, whereas no significant changes were noted for these hormones in women (20).Practitioners of sport disciplines in which a thin body is required for better performance are at risk for developin...