Lomax Mitch, Massey Heather C, House James R
Aerosp Med Hum Perform. 2017 Jun 1;88(6):544-549. doi: 10.3357/AMHP.4780.2017.
Hypoxic environments increase the physiological demands of exercise. Inspiratory muscle training can reduce the demands of exhaustive exercise in this environment. This study examined the impact of inspiratory muscle training on moderate intensity hypoxic cycling exercise.
There were 17 healthy adult men who undertook 4 wk of inspiratory muscle training (N = 8) or 4 wk of sham inspiratory muscle training (N = 9). Subjects completed four fixed intensity (100 W) and duration (10 min) cycle ergometry tests. Two were undertaken breathing normoxic ambient air and two breathing a hypoxic gas mixture (14.6% oxygen, balance nitrogen). One normoxic and hypoxic test occurred before, and one after, inspiratory muscle training.
Inspiratory muscle training increased maximal inspiratory mouth pressure by 21 ± 16 cmH2O. Arterial oxygen saturation and its ratio to minute ventilation also increased after inspiratory muscle training during hypoxic exercise from 83 ± 4% to 86 ± 3% (approximately 3%) and 2.95 ± 0.48 to 3.52 ± 0.54% · L · min-1(approximately 21%), respectively. In addition, minute ventilation and carbon dioxide output fell by 12-13% after inspiratory muscle training during hypoxic exercise.
Inspiratory muscle training reduced the physiological demand of moderate intensity exercise during acute hypoxic, but not normoxic, exercise. It may therefore be of benefit in adults exercising in a hypoxic environment.Lomax M, Massey HC, House JR. Inspiratory muscle training effects on cycling during acute hypoxic exposure. Aerosp Med Hum Perform. 2017; 88(6):544-549.
低氧环境会增加运动的生理需求。吸气肌训练可以降低在这种环境下进行力竭性运动的需求。本研究探讨了吸气肌训练对中等强度低氧骑行运动的影响。
17名健康成年男性，其中8人进行了4周的吸气肌训练，9人进行了4周的假吸气肌训练。受试者完成了四次固定强度（100瓦）和持续时间（10分钟）的自行车测力计测试。两次测试在呼吸常氧环境空气时进行，两次在呼吸低氧混合气体（氧气含量14.6%，其余为氮气）时进行。一次常氧和低氧测试在吸气肌训练前进行，另一次在吸气肌训练后进行。
吸气肌训练使最大吸气压增加了21±16厘米水柱。在低氧运动期间，吸气肌训练后动脉血氧饱和度及其与分钟通气量的比值也分别从83±4%增加到86±3%（约3%），从2.95±0.48增加到3.52±0.54%·升·分钟-1（约21%）。此外，在低氧运动期间，吸气肌训练后分钟通气量和二氧化碳排出量下降了12 - 13%。
吸气肌训练降低了急性低氧（而非常氧）运动期间中等强度运动的生理需求。因此，对于在低氧环境中运动的成年人可能有益。
洛马克斯M、梅西HC、豪斯JR。急性低氧暴露期间吸气肌训练对骑行的影响。航空航天医学与人类表现。2017；88(6):544 - 549。
