Sweeting Alice J, Billaut François, Varley Matthew C, Rodriguez Ramón F, Hopkins William G, Aughey Robert J
Institute of Sport, Exercise and Active Living, Victoria University Melbourne, VIC, Australia.
Institute of Sport, Exercise and Active Living, Victoria UniversityMelbourne, VIC, Australia; Département de Kinesiology, Université LavalQuébec, QC, Canada.
Front Physiol. 2017 Feb 10;8:80. doi: 10.3389/fphys.2017.00080. eCollection 2017.
To quantify the effect of acute hypoxia on muscle oxygenation and power during simulated team-sport running. Seven individuals performed repeated and single sprint efforts, embedded in a simulated team-sport running protocol, on a non-motorized treadmill in normoxia (sea-level), and acute normobaric hypoxia (simulated altitudes of 2,000 and 3,000 m). Mean and peak power was quantified during all sprints and repeated sprints. Mean total work, heart rate, blood oxygen saturation, and quadriceps muscle deoxyhaemoglobin concentration (assessed via near-infrared spectroscopy) were measured over the entire protocol. A linear mixed model was used to estimate performance and physiological effects across each half of the protocol. Changes were expressed in standardized units for assessment of magnitude. Uncertainty in the changes was expressed as a 90% confidence interval and interpreted via non-clinical magnitude-based inference. Mean total work was reduced at 2,000 m (-10%, 90% confidence limits ±6%) and 3,000 m (-15%, ±5%) compared with sea-level. Mean heart rate was reduced at 3,000 m compared with 2,000 m (-3, ±3 min) and sea-level (-3, ±3 min). Blood oxygen saturation was lower at 2,000 m (-8, ±3%) and 3,000 m (-15, ±2%) compared with sea-level. Sprint mean power across the entire protocol was reduced at 3,000 m compared with 2,000 m (-12%, ±3%) and sea-level (-14%, ±4%). In the second half of the protocol, sprint mean power was reduced at 3,000 m compared to 2,000 m (-6%, ±4%). Sprint mean peak power across the entire protocol was lowered at 2,000 m (-10%, ±6%) and 3,000 m (-16%, ±6%) compared with sea-level. During repeated sprints, mean peak power was lower at 2,000 m (-8%, ±7%) and 3,000 m (-8%, ±7%) compared with sea-level. In the second half of the protocol, repeated sprint mean power was reduced at 3,000 m compared to 2,000 m (-7%, ±5%) and sea-level (-9%, ±5%). Quadriceps muscle deoxyhaemoglobin concentration was lowered at 3,000 m compared to 2,000 m (-10, ±12%) and sea-level (-11, ±12%). Simulated team-sport running is impaired at 3,000 m compared to 2,000 m and sea-level, likely due to a higher muscle deoxygenation.
为了量化急性低氧对模拟团队运动跑步过程中肌肉氧合和功率的影响。七名受试者在常氧（海平面）和急性常压低氧（模拟海拔2000米和3000米）条件下，于非电动跑步机上按照模拟团队运动跑步方案进行重复和单次冲刺运动。在所有冲刺和重复冲刺过程中对平均功率和峰值功率进行量化。在整个方案过程中测量平均总功、心率、血氧饱和度以及股四头肌脱氧血红蛋白浓度（通过近红外光谱法评估）。使用线性混合模型估计方案各半程的运动表现和生理效应。变化以标准化单位表示以评估幅度。变化的不确定性以90%置信区间表示，并通过基于非临床幅度的推断进行解释。与海平面相比，在2000米（-10%，90%置信限±6%）和3000米（-15%，±5%）时平均总功降低。与2000米（-3，±3次/分钟）和海平面（-3，±3次/分钟）相比，在3000米时平均心率降低。与海平面相比，在2000米（-8，±3%）和3000米（-15，±2%）时血氧饱和度较低。与2000米（-12%，±3%）和海平面（-14%，±4%）相比，在3000米时整个方案的冲刺平均功率降低。在方案的后半程，与2000米相比，3000米时冲刺平均功率降低（-6%，±4%）。与海平面相比，在2000米（-10%，±6%）和3000米（-16%，±6%）时整个方案的冲刺平均峰值功率降低。在重复冲刺过程中，与海平面相比，在2000米（-8%，±7%）和3000米（-8%，±7%）时平均峰值功率较低。在方案的后半程，与2000米（-7%，±5%）和海平面（-9%，±5%）相比，3000米时重复冲刺平均功率降低。与2000米（-10，±12%）和海平面（-11，±12%）相比，在3000米时股四头肌脱氧血红蛋白浓度降低。与2000米和海平面相比，在3000米时模拟团队运动跑步受到损害，可能是由于更高的肌肉脱氧作用。
