EFFECTS OF REPEATED SPRINT TRAINING ON ISOCAPNIC BUFFERING PHASE IN VOLLEYBALL PLAYERS

ABSTRACT Introduction: The region between the ventilatory threshold (VT) and respiratory compensation point (RCP) is defined as the isocapnic buffering (ICB) phase and represents a phase of compensation for exercise-induced metabolic acidosis. There is sparse literature examining the effects of physical training on ICB phase in athletes. Objectives: The purpose of this study was to examine the effects of a repeated sprint training program on the ICB phase of college volleyball players. Methods: Eighteen male volleyball players were randomly assigned to either an experimental group (n=9) or a control group (n=9) and followed a traditional volleyball training program three times per week for six weeks. The experimental group additionally performed a repeated sprint training protocol immediately before each volleyball training session. Before and after the 6-week training period, all participants performed an incremental treadmill test to determine VT, RCP, and maximal oxygen uptake (VO2max). The ICB phases were calculated as VO2 (ml/kg/min) and sprint speed (km/h). Results: The experimental group showed significant improvements in ICB phase, RCP, VO2max and maximal sprint speed after training (p<0.01). There were no significant changes in VT after training in the experimental group (p>0.05). None of these variables changed significantly in the control group (p>0.05). Conclusions: These findings indicate that repeated sprint training can enhance the ICB phase of volleyball players, which may be attributable to an improvement in buffering capacity leading to a shift in RCP towards higher intensities without any change in VT. The increase in the ICB phase may an important factor in terms of improvement in the high-intensity exercise tolerance of athletes. Level of Evidence II; Therapeutic studies - Investigating the results of treatment.

摘要
引言：通气阈（ventilatory threshold, VT）与呼吸补偿点（respiratory compensation point, RCP）之间的区域被定义为等碳酸缓冲（isocapnic buffering, ICB）期，该时期代表了对运动诱导代谢性酸中毒的代偿阶段。目前针对运动员等碳酸缓冲期受身体训练影响的相关研究较为匮乏。
研究目的：本研究旨在探讨重复冲刺训练方案对大学排球运动员等碳酸缓冲期的影响。
方法：将18名男子排球运动员随机分为实验组（n=9）与对照组（n=9），两组均每周进行3次传统排球训练，持续6周。实验组在每次排球训练前额外完成一套重复冲刺训练方案。在6周训练周期前后，所有受试者均完成递增负荷跑台试验，以测定通气阈、呼吸补偿点及最大摄氧量（maximal oxygen uptake, VO2max）。等碳酸缓冲期以摄氧量（单位：ml/kg/min）与冲刺速度（单位：km/h）进行计算。
结果：训练后，实验组的等碳酸缓冲期、呼吸补偿点、最大摄氧量及最大冲刺速度均出现显著提升（p<0.01）。实验组的通气阈在训练后无显著变化（p>0.05）。对照组的上述各项指标均未出现显著变化（p>0.05）。
结论：本研究结果表明，重复冲刺训练可提升排球运动员的等碳酸缓冲期，这可能归因于缓冲能力的改善，使得呼吸补偿点向更高强度偏移，而通气阈未发生改变。等碳酸缓冲期的延长可能是提升运动员高强度运动耐受力的重要因素。
证据等级：Ⅱ级；治疗性研究——探究治疗效果的研究。