Effects of rapid weight loss and wrestling on muscle glycogen concentration
Deutscher übersetzter Titel: | Auswirkungen von akutem Gewichtsverlust im Ringen auf die Muskelglykogenkonzentration |
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Autor: | Tarnopolsky, M.A.; Cipriano, N.; Woodcroft, C.; Pulkkinen, W.J.; Robinson, D.C.; Henderson, J.M.; MacDougall, J.D. |
Erschienen in: | Clinical journal of sport medicine |
Veröffentlicht: | 6 (1996), 2, S. 78-84, Lit. |
Format: | Literatur (SPOLIT) |
Publikationstyp: | Zeitschriftenartikel |
Medienart: | Gedruckte Ressource |
Sprache: | Englisch |
ISSN: | 1050-642X, 1536-3724 |
Schlagworte: | |
Online Zugang: | |
Erfassungsnummer: | PU199704203873 |
Quelle: | BISp |
Abstract des Autors
Objective: To examine the effect of energy restriction and wrestling on muscle glycogen content in highly-trained male wrestlers. Design: Randomized, unblinded intervention trial. Setting: McMaster University Nutrition and Metabolism Research Laboratory. Participants: Twelve highly trained male wrestlers volunteered as subjects and were randomly assigned to one of two groups (Group A, n=6; Group B, n=6) as defined below. Assessment of risk factors: All subjects were free of medical conditions that would preclude participation in the study and all had performed rapid weight loss at least three times/year with no medical complications. Interventions: Group A: simulated wrestling tournament, four 5-min wrestling bouts (>7 h) following a 5% body weight loss and 17 h repletion period; Group B: 5% weight loss through energy restriction (1,141 kcal/day), exercise, fluid restriction, and dehydration methods (sauna) >72 h. Main outcome measures: Group A: muscle glycogen content before and after wrestling tournament and plasma lactate after each bout; Group B: muscle glycogen before and after weight loss. Results: Group A: no significant effect on muscle glycogen concentration, yet large increases were observed in blood lactate concentrations (up to 14.7 mmol/L); Group B: weight loss resulted in a 54% (p<0.018) reduction in muscle glycogen concentration. Conclusions: The weight loss methods commonly performed by wrestlers resulted in large decreases in muscle glycogen concentration that were largely reversed during the 17-h repletion period between weigh-in and the start of the competition; participation in a wrestling tournament did not have a significant impact upon biceps brachii glycogen concentration when ad libitum feeding is alowed between matches. Verf.-Referat