糖原填充对马拉松运动成绩的影响

Carbohydrate loading and marathon performance

在马拉松训练与比赛中,肌糖原的耗竭和降低,与运动性疲劳的发生有着密切关系,肌糖原在体内的有氧氧化供能是马拉松训练和竞赛中机体主要的能量来源。赛前糖原填充的方法能够提高运动能力,推迟疲劳来临的时间。对优秀运动员而言,在运动竞赛前36～48小时,通过递减运动量,摄入10～12g/kg/d的糖,以达到赛前糖原填充的要求。运动营养学指出在两次训练间隙,充足糖的摄入,能够有效促进肌糖原的恢复,运动员就可以持续不断的从事训练和得到有效恢复。有人认为机体低糖储备在训练时会产生强烈的应答反应,但事实上低糖饮食对提高马拉松运动成绩不利。有研究表明,长期的低糖饮食对运动能力是有害的,在赛前增加体内糖原的储量,对马拉松运动员来说是十分必要的。

Muscle glycogen aerobic oxidation provides a key fuel for training and racing a marathon.Muscle glycogen depletion and reduced associate with exercise-induced fatigue.Carbohydrate loading before training and competition can enhance marathon performance before fatigue.For the well trained runner,this may be achieved by tapering exercise over the final days before the marathon and ensuring carbohydrate intakes of 10g/kg/d～12 g/kg/d over the 36～48 hours prior to the race.Sports nutrition guidelines recommend that the runner consumes sufficient carbohydrate to promote restoration of muscle glycogen between training sessions.A researcher assumption that athlete training with low glycogen stores might promote greater stimulation of the training response.In fact,a low carbohydrate diet may even impair performance.It is necessary to increase muscles glycogen stores for marathon athletes before competition.