Effects of Rapid Weight Reduction on Protein Metabolism in Boxing Players / 体力科学

The purpose of the present study is to investigate protein metabolism during rapid weight reduction. Six male boxing players put on a restricted diet of their own accord for two weeks. Body weight changes were observed and a biochemical analysis was made of their urine and blood. The initial body weight of 66.1±3.0kg (mean±SE) decreased to 63.6±3.2 kg after two weeks (P<0.01) . The changes in lean body mass (LBM) by weight reduction were not significant, but the LBM tended to decrease after two weeks. The mean caloric intake was 2, 791±728 kcal before the study and 1, 643±548 kcal after two weeks. The reduction of carbohydrate consumption is much more than that of fat and protein consumption. The 3-Me/Cr in urine increased significantly after two weeks (348.1 ± 37.0 μol/g to 508.1 f 45.6 μmol/g, P<0.01) and the increase of Urea-N/Cr in urine (8.4±0.5mg/mg creatinine to 13.7±1.3mg/mg creatinine, P<0.01) was also significant after two weeks. Urine volume decreased significantly after two weeks (P<0.01) . There was no significant difference in the blood components during the weight reduction period. These results might suggest that rapid weight reduction and massive decrease of carbohydrate intake accelerate protein catabolism.

Effects of rapid weight reduction on the body water and nitrogen balance in wrestlers / 体力科学

Six wrestlers, whose body weights should be reduced 4-11% in relatively short period of time to be acknowledged for intercollegeate 62 kg class competition, were selected and their daily food intakes in regulation, reduction through recovery period of body weights were estimated. Simultaneously, the weights of whole urine and feces were estimated, and some urine components were analysed.<BR>Nutrients intake except calsium and iron were maintained allowance level in regulation period, and reduced through reduction period. On third day of recovery period, the body weights were recovered to their own level, but through the period, only the intake of energy, water, sodium and vitamin A were recovered to the level of regulation period. Personal deviations in their intakes of vitamin B complex and C were distinkt, and the iron intake was under level through all period.<BR>The average body water contents was 68%, estimated by D<SUB>2</SUB>0 method. Negative water and nitrogen balance through regulation and reduction period turned to positive in recovery period, but not completely recovered to their nomal level.