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 allowed between matches.
RCT Entities:
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 allowed between matches.
Authors: Paula Sammarone Turocy; Bernard F DePalma; Craig A Horswill; Kathleen M Laquale; Thomas J Martin; Arlette C Perry; Marla J Somova; Alan C Utter Journal: J Athl Train Date: 2011 May-Jun Impact factor: 2.860
Authors: A Aloui; H Chtourou; W Briki; M Tabben; A Chaouachi; N Souissi; R J Shephard; K Chamari Journal: Biol Sport Date: 2016-11-10 Impact factor: 2.806
Authors: J G Pallarés; A Martínez-Abellán; J M López-Gullón; R Morán-Navarro; E De la Cruz-Sánchez; R Mora-Rodríguez Journal: J Int Soc Sports Nutr Date: 2016-03-08 Impact factor: 5.150