【作者】 郭浙斌；

【导师】 黄玉山；

【作者基本信息】 华南师范大学 ， 运动人体科学， 2007， 硕士

【摘要】 低氧训练作为现代竞技运动中模拟高原训练的有效手段已引起广泛的关注，它通过低氧和运动的双重刺激，提高心肺功能，改善氧运输和骨骼肌利用氧的能力，使运动员的运动能力得以提高。运动中脱水作为引发机体疲劳的重要诱因，在低氧训练中往往被忽略，从而影响训练效果。本文通过观察低氧和常氧环境下一次性力竭运动中补液或不补液使机体裸体体重、血清渗透压、尿比重、血清离子浓度、血压、血乳酸、运动时间、心率及自主体力感觉（RPE）等相关指标所发生的变化，探讨了补液对低氧和常氧环境下机体体液平衡和运动能力的影响，以期为低氧训练过程中的合理补液提供实验依据，并在训练中对脱水加以预防和监控，以达到更好的训练效果。实验以体育学院7名男生为研究对象，在人工低氧运动训练棚内（低氧和常氧环境），利用功率自行车以70％最大摄氧量(VO_2max)的强度进行一次性力竭运动。根据环境氧浓度的不同和运动过程中是否补液分为常氧不补液运动组（NC：常氧对照组）、常氧补液运动组（NF）、低氧不补液运动组（HE）和低氧补液运动组（HF），并分别对其运动前后的相关指标进行测试，数据以SPSS统计软件进行处理。结果与提示：（1） HE组和NC组运动后体重下降，血清渗透压升高，说明机体已处于脱水状态，机体的水代谢失衡。但HE组和NC组运动前后体重的变化率和血清渗透压的升高率并未出现显著性差异，提示低氧环境下持续时间不长的运动对机体水平衡的影响与常氧环境相似。HF组运动前后的体重变化率和运动后即刻的血清渗透压变化率明显低于HE组，提示低氧环境中补液可有效地改善由运动引发的机体水代谢失衡。（2） HE组运动后血清中Na⁺和Cl^-的浓度均未发生显著性变化，而在HF组中，在运动后血清Na⁺和Cl^-的浓度有下降的趋势，提示饮料中Na⁺和Cl^-的浓度会对血清离子浓度造成影响，在补液中应对Na⁺和Cl^-的浓度加以控制。HE组和HF组中，血清K⁺浓度均显著升高，在运动后30分钟，HF组血清中K⁺浓度较即刻显著下降，而HE组中K⁺浓度没有变化，具体生理学机制有待研究。（3） HE组运动至力竭的时间要明显短于NC组，RPE-时间曲线左移；而当补液时，HF组运动至力竭的时间较HE组得到明显提高，RPE-时间曲线右移。提示，机体采用与常氧环境下同等强度的负荷在低氧环境下进行运动时，所产生的相对生理负荷更大。（4）在相同负荷下，HE组与时间相对应的心率变化曲线较NC组左移，HF组与时间相对应的心率变化曲线较HE组右移。NF和HF组较NC和HE组的血压下降幅度减小，说明补液对于维持心率和血压的稳定有重要的作用。（5） HE组运动后血乳酸值较NC组显著性增加，说明低氧下乳酸积聚的速度加快；而HF组运动后血乳酸值较HE组显著性降低。提示补液对于代谢产物的形成和消除有一定的作用。运动后HE组的血糖浓度明显高于NC组，这可能是由于运动与急性缺氧的双重刺激，使机体交感-肾上腺系统一直处于较高的应激水平，加速了肝糖原的分解。而HF组在运动后血糖水平升高幅度较HE组更高，说明外源性糖的摄入对维持血糖水平有一定帮助，从而可达到节省糖原的目的。更多还原

【Abstract】 Hypoxic training, which has been shown to increase cardiopulmonary function,maximum oxygen uptake and skeletal muscle capillary, as effective approach forstudies aimed at evaluating altitude exercise has attracted attention of researchers onsports. Despite important role of dehydration in exercise, researchers generallyneglected it in hypoxic condition. The purpose of this study was to explore the effectof carbohydrate-electrolyte solution（CE） ingestion on body fluid balance and exerciseability in different O₂ concentration environments, and supply more experimental datafor rational CE ingestion in hypoxic training by measured relative indexes duringhypoxic or normoxic single bout of exhaustive exercise with or without rehydrationsolution, such as nude weight, serum osmolality, urine specific gravity, serum ionsconcentration, blood pressure, body temperature, blood lactate, exercise duration,heart rate and rating of perceived exertion（RPE）. Therefore, we can guide athleticstraining by preventing and observing dehydration.Seven male students in college of physical education taked single bout ofexhaustive exercise on bicycle ergometer at 70%VO_2max in an artifical hypoxicroom（normobaric hypoxic environment and normobaric normoxic environment）. Thesubjects were separated to 4 groups based on different oxygen concentration and thecondition of rehydration solution during exercise: normoxic control（NC）; hypoxicexercise（HE）; normoxic fluid（NF）; hypoxic fluid（HF）. The data after trainingcompared with that before exercise and analyzed by SPSS.ConclusionWeight-lost and raise of serum osmolality were observed in both 4 groups,specially in HE and NC groups and the serum osmolality recuperated within30minutes after training, which showed that dehydration in normoxic and hypoxicexercises and the rate of back to body fluid balance could be improved by CEingestion. The sweat exhausting rate during exercise of NF group was lower than thatof NC, while the contrary result showed in the compare between HF group and HEgroup. One possibility may be due to changes of subjects’ sweat exhaustingmachanism under hypoxic exposure. It is suggested that rehydration was needed to improve the state of body hydration during hypoxic and normxic exercises. However,hypoxic rehydration differed from normoxia according to changes of physiologymechanism （especiall body fluid balance mechanism） caused by hypoxia.There was appreciable increase of serum [Na⁺] and [Cl^-] in NC and HE afterexercise; while decrease observed in NF and HF, and then decreased significantlywithin 30 minutes after exercise. It is speculated that this related to the lowconcentration of Na⁺ and Cl^- in supplementary. Increase of serum [K⁺] was present inall groups and was positive correlated with duration, especially significant in HE andHF, while sharp decrease of [Na⁺] was shown in HF at 30 minutes after training.The physiological mechanism is not clear, and further studies would be necessary toclarify the issue.With same exercise workload, HR-time curve of HE turned to move rightcompared with that of NC; there was deep degree of decrease of pressure afterexercise. Therefore, exercise workload same as under normoxia was relativelyenlarged under hypoxic exposure.HR-time curve of HF and NF turned to move right compared with those of HEand NC, there was small scope of blood pressure, there is a special function ofmaintain HR and BP by CE ingestion.Significant increase of blood lactate was observed in HE compared to NC, whichsuggested speed of lactate gather was faster in hypoxia; there were significantdecreases of blood lactate both in HF and NF compare to HE and NC. These resultsshowed that CE ingestion has certain action on appearance and clearance ofmetabolite. The blood sugar concentration in HE was higher than that in NC, perhapsdue to double stimulations of exercise and hypoxia which maintained excitation ofsympathetic-adrenal-system and accelerated Glycogenolysis. There was significantlyhigher increase of blood sugar in HF, which suggested that blood sugar concentrationcould be kept and hepatin could be saved by glucose uptake.更多还原