Hiroyuki Sagayama1, Emi Kondo2, Yoko Tanabe3, Takahiro Ohnishi2, Yosuke Yamada4, Hideyuki Takahashi2. 1. Faculty of Health and Sport Sciences, University of Tsukuba, Ibaraki, Japan. Electronic address: sagayama.hiroyuki.ka@u.tsukuba.ac.jp. 2. Japan Institute of Sports Sciences, Tokyo, Japan. 3. Faculty of Health and Sport Sciences, University of Tsukuba, Ibaraki, Japan. 4. National Institute of Health and Nutrition, Tokyo, Japan.
Abstract
BACKGROUND: Weight-bearing physical activity and intense mechanical stimuli affect the bone through the endocrine system; hence, bone-loading sports affect bone mineral density. We hypothesized that weight-classified athletes, such as those practicing wrestling and judo, have relatively high bone mineral density because these activities have a higher impact on the entire body during daily training compared to low- or non-impact activities. We aimed to investigate the bone mineral density of weight-classified athletes (participating in wrestling and judo) to compare the parameters with those of endurance-athletes and non-athletes. METHODS: Thirty-three college athletes (aged 18-22 years) were divided into three groups, wrestlers, judoka, and endurance-athletes, according to their sports history. Eight non-athletes participated as controls. Bone mineral density was determined by whole-body dual-energy X-ray absorptiometry. RESULTS: Mean whole-body bone mineral density of wrestlers and judoka was higher than that of endurance-athletes and non-athletes (P < 0.01). The bone mineral density of athletes competing in wrestling and judo was higher than that of non-athletes when adjusted for body mass. CONCLUSIONS: The present study demonstrated that weight-classified athletes have significantly higher bone mineral density compared to endurance- and non-athletes, despite rapid weight loss before competitions.
BACKGROUND: Weight-bearing physical activity and intense mechanical stimuli affect the bone through the endocrine system; hence, bone-loading sports affect bone mineral density. We hypothesized that weight-classified athletes, such as those practicing wrestling and judo, have relatively high bone mineral density because these activities have a higher impact on the entire body during daily training compared to low- or non-impact activities. We aimed to investigate the bone mineral density of weight-classified athletes (participating in wrestling and judo) to compare the parameters with those of endurance-athletes and non-athletes. METHODS: Thirty-three college athletes (aged 18-22 years) were divided into three groups, wrestlers, judoka, and endurance-athletes, according to their sports history. Eight non-athletes participated as controls. Bone mineral density was determined by whole-body dual-energy X-ray absorptiometry. RESULTS: Mean whole-body bone mineral density of wrestlers and judoka was higher than that of endurance-athletes and non-athletes (P < 0.01). The bone mineral density of athletes competing in wrestling and judo was higher than that of non-athletes when adjusted for body mass. CONCLUSIONS: The present study demonstrated that weight-classified athletes have significantly higher bone mineral density compared to endurance- and non-athletes, despite rapid weight loss before competitions.