吸氣肌熱身對於低氧環境中漸增負荷運動表現之影響

The Effect of Inspiratory Muscle Warm-Up on Incremental Exercise Test Performance in Hypoxic Environment

目的：探討低氧環境下吸氣肌熱身對隨後漸增負荷腳踏車運動表現的效益。方法：受試者為12名男性，年齡20.58±0.90歲並有運動習慣。實驗設計以交叉平衡次序原則，分為低氧環境＋吸氣肌熱身處理（hypoxic environment of inspiratory muscle warm-up, HEIMW）及低氧環境處理（hypoxic environment, HE），進行漸增負荷腳踏車運動，比較不同的實驗處理後肺功能、吸氣肌肌力、呼吸頻率、心跳率、血氧濃度、換氣量、運動自覺量表、呼吸困難自覺量表、血乳酸及運動表現的變化情形。結果：低氧環境＋吸氣肌熱身及低氧環境組的測驗指標，如肺功能、吸氣肌肌力、心跳率、血氧濃度、運動自覺量表、呼吸困難自覺量表、血乳酸及運動表現，兩組間皆無顯著差異（p＞.05）。而在運動時間中位數後2分鐘，HEIMW呼吸頻率及換氣量明顯較HE高（呼吸頻率 HEIMW vs. HE, 34.83±10.43 vs. 32.83±11.15次／分, p＜.05；換氣量 HEIMW vs. HE, 68.5±8.82 vs. 67.08±7.93 L/min, p＜.05），並且在耗竭前2分鐘呼吸頻率明顯高於低氧環境組（HE vs. HEIMW, 47.80±13.50 vs. 50.88±13.03次／分, p＜.05）。結論：低氧環境下進行吸氣肌熱身，會使隨後漸增負荷腳踏車測驗，在運動時間中位數後2分鐘及運動耗竭前2分鐘的呼吸頻率及換氣量上升，造成代償及呼吸急促的現象。

Purpose: To investigate the effects of hypoxic environment inspiratory muscle warm-up (HEIMW) on incremental exercise test performance. Methods: The subjects were 12 males (age, 20.58±0.90 years) with exercise habits. The experimental design is repeated measures and crossover designed study, divided into HEIMW group and hypoxic environment (HE) group, for incremental exercise test. Compare the changes in lung function, inspiratory muscle strength, breathing frequency (BF), heart rate (HR), oxyhemoglobin saturation by pulse oximetry (SPO2), ventilation volume (VE), rating of perceived exertion (RPE), rating of perceived breathlessness (RPB), blood lactate and exercise performance after different experimental treatments. Results: Test indicators of HEIMW group and HE group, such as lung function, inspiratory muscle strength, HR, SPO2, RPE, RPB, blood lactic acid and sports performance, there was no significant difference between the two groups (p > .05). However, 2 minutes after the median exercise time, the BF and VE of the HEIMW group were significantly higher than HE group (BF, HEIMW vs. HE, 32.83±11.15 vs. 34.83±10.43, p <.05；VE, HEIMW vs. HE, 67.08±7.93 vs. 68.5±8.82 L/min, p < .05). Two minutes before exercise exhaustion, the BF was significantly higher than HE group (HE vs. HEIMW, 47.80±13.50 vs. 50.88±13.03, p < .05). Conclusions: In the HEIMW group, the subsequent increasing incremental exercise test will increase BF and VE 2 minutes after the median exercise time and 2 minutes before exercise exhaustion, resulting in compensatory and shortness of breath.