ASPETAR Qatar Orthopaedic and Sports Medicine Hospital, Research and Education Centre, Doha, Qatar.
Sports Med. 2011 Aug 1;41(8):673-94. doi: 10.2165/11590550-000000000-00000.
Short-duration sprints (<10 seconds), interspersed with brief recoveries (<60 seconds), are common during most team and racket sports. Therefore, the ability to recover and to reproduce performance in subsequent sprints is probably an important fitness requirement of athletes engaged in these disciplines, and has been termed repeated-sprint ability (RSA). This review (Part I) examines how fatigue manifests during repeated-sprint exercise (RSE), and discusses the potential underpinning muscular and neural mechanisms. A subsequent companion review to this article will explain a better understanding of the training interventions that could eventually improve RSA. Using laboratory and field-based protocols, performance analyses have consistently shown that fatigue during RSE typically manifests as a decline in maximal/mean sprint speed (i.e. running) or a decrease in peak power or total work (i.e. cycling) over sprint repetitions. A consistent result among these studies is that performance decrements (i.e. fatigue) during successive bouts are inversely correlated to initial sprint performance. To date, there is no doubt that the details of the task (e.g. changes in the nature of the work/recovery bouts) alter the time course/magnitude of fatigue development during RSE (i.e. task dependency) and potentially the contribution of the underlying mechanisms. At the muscle level, limitations in energy supply, which include energy available from phosphocreatine hydrolysis, anaerobic glycolysis and oxidative metabolism, and the intramuscular accumulation of metabolic by-products, such as hydrogen ions, emerge as key factors responsible for fatigue. Although not as extensively studied, the use of surface electromyography techniques has revealed that failure to fully activate the contracting musculature and/or changes in inter-muscle recruitment strategies (i.e. neural factors) are also associated with fatigue outcomes. Pending confirmatory research, other factors such as stiffness regulation, hypoglycaemia, muscle damage and hostile environments (e.g. heat, hypoxia) are also likely to compromise fatigue resistance during repeated-sprint protocols.
短时间的冲刺（<10 秒），穿插短暂的恢复期（<60 秒），在大多数团队和球拍运动中很常见。因此，运动员在这些项目中可能需要具备恢复和在随后的冲刺中重现表现的能力，这被称为重复冲刺能力（RSA）。这篇综述（第一部分）探讨了疲劳在重复冲刺运动（RSE）中是如何表现的，并讨论了潜在的肌肉和神经机制。本文的后续配套综述将解释对训练干预措施的更好理解，这最终可能会提高 RSA。使用实验室和现场协议，性能分析一致表明，RSE 期间的疲劳通常表现为最大/平均冲刺速度（即跑步）的下降，或在冲刺重复中峰值功率或总功（即骑自行车）的下降。这些研究的一个一致结果是，连续回合中的表现下降（即疲劳）与初始冲刺表现呈反比。迄今为止，毫无疑问，任务的细节（例如工作/恢复期的性质变化）改变了 RSE 期间疲劳发展的时间过程/幅度（即任务依赖性），并可能改变潜在机制的贡献。在肌肉水平上，能量供应的限制，包括磷酸肌酸水解、无氧糖酵解和氧化代谢提供的能量，以及代谢副产物（如氢离子）在肌肉内的积累，成为导致疲劳的关键因素。尽管没有得到广泛研究，但表面肌电图技术的使用表明，未能充分激活收缩肌肉和/或改变肌肉募集策略（即神经因素）也与疲劳结果有关。在确认性研究之前，其他因素，如刚度调节、低血糖、肌肉损伤和恶劣环境（如热、缺氧）也可能在重复冲刺方案中降低疲劳抵抗力。
