Cruz Rogério Santos de Oliveira, de Aguiar Rafael Alves, Turnes Tiago, Salvador Amadeo Félix, Caputo Fabrizio
Human Performance Research Group, Center for Health and Sport Science, Santa Catarina State University (CEFID/UDESC), Florianópolis, Santa Catarina, CEP, 88080-350, Brazil.
Appl Physiol Nutr Metab. 2016 Aug;41(8):825-31. doi: 10.1139/apnm-2015-0646. Epub 2016 Mar 30.
It has been demonstrated that ischemic preconditioning (IPC) improves endurance performance. However, the potential benefits during anaerobic events and the mechanism(s) underlying these benefits remain unclear. Fifteen recreational cyclists were assessed to evaluate the effects of IPC of the upper thighs on anaerobic performance, skeletal muscle activation, and metabolic responses during a 60-s sprint performance. After an incremental test and a familiarization visit, subjects were randomly submitted in visits 3 and 4 to a performance protocol preceded by intermittent bilateral cuff inflation (4 × (5 min of blood flow restriction + 5 min reperfusion)) at either 220 mm Hg (IPC) or 20 mm Hg (control). To increase data reliability, each intervention was replicated, which was also in a random manner. In addition to the mean power output, the pulmonary oxygen uptake, blood lactate kinetics, and quadriceps electromyograms (EMGs) were analyzed during performance and throughout 45 min of passive recovery. After IPC, performance was improved by 2.1% compared with control (95% confidence intervals of 0.8% to 3.3%, P = 0.001), followed by increases in (i) the accumulated oxygen deficit, (ii) the amplitude of blood lactate kinetics, (iii) the total amount of oxygen consumed during recovery, and (iv) the overall EMG amplitude (P < 0.05). In addition, the ratio between EMG and power output was higher during the final third of performance after IPC (P < 0.05). These results suggest an increased skeletal muscle activation and a higher anaerobic contribution as the ultimate responses of IPC on short-term exercise performance.
已有研究表明，缺血预处理（IPC）可提高耐力表现。然而，在无氧运动期间的潜在益处以及这些益处背后的机制仍不明确。对15名休闲自行车运动员进行评估，以评价大腿上部IPC对60秒冲刺表现期间的无氧运动表现、骨骼肌激活及代谢反应的影响。在进行递增测试和熟悉训练后，受试者在第3次和第4次测试中被随机分为两组，分别在220毫米汞柱（IPC组）或20毫米汞柱（对照组）下进行间歇性双侧袖带充气（4×（5分钟血流限制+5分钟再灌注）），随后进行运动表现测试。为提高数据可靠性，每种干预措施均以随机方式重复进行。除平均功率输出外，还在运动期间及45分钟被动恢复过程中分析了肺摄氧量、血乳酸动力学及股四头肌肌电图（EMG）。与对照组相比，IPC后运动表现提高了2.1%（95%置信区间为0.8%至3.3%，P = 0.001），随后出现以下增加情况：（i）累积氧亏；（ii）血乳酸动力学幅度；（iii）恢复期间消耗的总氧量；（iv）整体EMG幅度（P < 0.05）。此外，IPC后运动最后三分之一时间内EMG与功率输出的比值更高（P < 0.05）。这些结果表明，骨骼肌激活增加和更高的无氧贡献是IPC对短期运动表现的最终反应。
