目的:本研究的目的是调查耐力超支运动员在运动过程中碳水化合物的利用是否发生改变,并研究连续血糖监测仪(CGM)检测超支状态的效用。
方法:11名耐力运动员(M:8,F:3)完成了为期5周的训练,包括1周的减量训练(PRE),3周高强度超负荷训练(POST),和1周的恢复训练(REC)。参与者在PRE完成了Lamberts和Lambert次最大循环测试(LSCT)和5km计时赛,POST,和REC时间点,摄入50g葡萄糖饮料后15分钟,每分钟通过CGM记录葡萄糖。
结果:在5km计时赛中的性能在POST时降低(Δ-7±10W,p=0.04,ηp2$${\\upeta_{\\mathrm{p}}}^2$$=0.35),并在REC处得到改进(来自PRE的Δ12±9W,p=0.01,ηp2$${\\upeta_{\\mathrm{p}}}^2$$=0.66),随着乳酸峰值的降低(Δ-3.0±2.0mmol/L,p=0.001,ηp2$${\\upeta_{\\mathrm{p}}}^2$$=0.71),峰值HR(Δ-6±3bpm,p<0.001,ηp2$${\\upeta_{\\mathrm{p}}}^2$$=0.86),和Hooper-Mackinnon幸福感得分(Δ10±5a.u.,p<0.001,ηp2$${\\upeta_{\\mathrm{p}}}^2$$=0.79),表明运动员在功能上超支。在60%期间,相对于REC,呼吸交换比在POST时受到抑制(POST:0.80±0.05,REC:0.87±0.05,p<0.001,ηp2$${\\\upeta_{\\mathrm{p}}}^2$$$=0.74),和80%(POST:0.93±0.05,REC:1.00±0.05,p=0.003,ηp2$${\\upeta_{\\mathrm{p}}}^2$$=0.68)的HR匹配次最大阶段的LSCT。在LSCT的HR匹配的次最大运动期间,CGM葡萄糖降低了(p=0.047,ηp2$${\\upeta_{\\mathrm{p}}}^2$$=0.36),但不是5公里的计时赛(p=0.07,ηp2$${\\\upeta_{\\mathrm{p}}}^2$$=0.28)。
结论:这项初步研究表明,在过度锻炼的运动员亚最大运动期间,CGM衍生的葡萄糖和碳水化合物氧化减少。在标准化营养后的次最大运动中使用CGM可以用作监测工具,以检测耐力运动员的过度伸张。
OBJECTIVE: The purpose of the study was to investigate whether carbohydrate utilization is altered during exercise in overreached endurance athletes and examine the utility of continuous glucose monitors (CGM) to detect overreaching status.
METHODS: Eleven endurance athletes (M:8, F:3) completed a 5-week training block consisting of 1 week of reduced training (PRE), 3 weeks of high-intensity overload training (POST), and 1 week of recovery training (REC). Participants completed a Lamberts and Lambert Submaximal Cycling Test (LSCT) and 5 km time-trial at PRE, POST, and REC time points, 15 min following the ingestion of a 50 g glucose beverage with glucose recorded each minute via CGM.
RESULTS: Performance in the 5 km time-trial was reduced at POST (∆-7 ± 10 W, p = 0.04, η p 2 = 0.35) and improved at REC (∆12 ± 9 W from PRE, p = 0.01, η p 2 = 0.66), with reductions in peak lactate (∆-3.0 ± 2.0 mmol/L, p = 0.001, η p 2 = 0.71), peak HR (∆-6 ± 3 bpm, p < 0.001, η p 2 = 0.86), and Hooper-Mackinnon well-being scores (∆10 ± 5 a.u., p < 0.001, η p 2 = 0.79), indicating athletes were functionally overreached. The respiratory exchange ratio was suppressed at POST relative to REC during the 60% (POST: 0.80 ± 0.05, REC: 0.87 ± 0.05, p < 0.001, η p 2 = 0.74), and 80% (POST: 0.93 ± 0.05, REC: 1.00 ± 0.05, p = 0.003, η p 2 = 0.68) of HR-matched submaximal stages of the LSCT. CGM glucose was reduced during HR-matched submaximal exercise in the LSCT at POST (p = 0.047, η p 2 = 0.36), but not the 5 km time-trial (p = 0.07, η p 2 = 0.28) in overreached athletes.
CONCLUSIONS: This preliminary investigation demonstrates a reduction in CGM-derived glucose and carbohydrate oxidation during submaximal exercise in overreached athletes. The use of CGM during submaximal exercise following standardized nutrition could be employed as a monitoring tool to detect overreaching in endurance athletes.