| 摘要: | 目的：探討短期吸氣肌訓練對急性高地暴露後心血管反應與調控之影響。方法：15名男子大專公開組徑賽選手 (年齡為21.3 ± 2.15歲、身高為177.9 ± 6.19公分、體重為64.3 ± 8.49公斤) 自願參與本實驗，每位受試者於前測時進行生理檢測獲取安靜心跳率、血壓、脈波傳導速度、心率變異性以及心肌膜下活力率等數據，並進行最大吸氣壓力檢測 (maximal inspiratory pressure, PImax) 作為吸氣肌訓練的依據，以及最大運動測驗測得個體最大攝氧量。而後，受試者隨機分配至實驗組與控制組並分別以75 % PImax及15 % PImax進行4週吸氣肌訓練。吸氣肌訓練後進行7日高地環境暴露，並於回到海平面3日內完成後測。結果：實驗組與控制組兩組間安靜心跳率、血壓、脈波傳導速度、心率變異性、心肌膜下活力率以及最大攝氧量於各時間點並無顯著差異，然而，實驗組PImax海平面後測值顯著高於控制組 (180.8 ± 6.96 vs. 138.5 ± 7.35 cm H2O, p <.05)，實驗組最大攝氧量海平面後測值顯著高於前測值 (55.9 ± 1.35 vs. 48.7 ± 2.02 ml/kg/min , p <.05)。結論：短期海平面吸氣肌訓練無法改善高地環境時的最大攝氧量以及心血管反應與調控。但短期吸氣肌訓練後進行高地環境暴露，返回海平面後可提升PImax及最大攝氧量。
Purpose: To investigate the effects of short-term inspiratory muscle training on the cardiovascular response and modulation after acute high altitude exposure. Methods: Fifteen male college track and field athletes (age: 21.3 ± 2.15 years, height: 177.9 ± 6.19 cm, weight: 64.3 ± 8.49 kg) volunteered to participate in this study. Each subject underwent a pre-test to obtain data on resting heart rate, blood pressure, pulse wave velocity, heart rate variability, subendocardial viability ratio, and performed maximal inspiratory pressure (PImax) test for inspiratory muscle training, and maximal exercise test to measure maximal oxygen uptake. Subjects were then randomly assigned to experimental and control groups and underwent 4 weeks of inspiratory muscle training at 75 % PImax and 15 % PImax, respectively. Inspiratory muscle training was followed by 7 days of exposure to the high altitude environment and post-testing was completed within 3 days of return to sea level. Results: There were no significant differences in resting heart rate, blood pressure, pulse wave velocity, heart rate variability, subendocardial viability ratio and maximal oxygen uptake between the experimental and control groups at all time points; however, PImax in the experimental groups were significantly higher than those in the control groups at post-sea level (180.8 ± 6.96 vs. 138.5 ± 7.35 cm H2O, p < .05), maximal oxygen uptake in the experimental group was significantly higher at post-sea level than at pre-sea level (55.9 ± 1.35 vs. 48.7 ± 2.02 ml/kg/min , p <.05). Conclusion: Short-term sea-level inspiratory muscle training did not improve maximal oxygen uptake and cardiovascular responses and regulation in high altitude environment. However, short-term inspiratory muscle training followed by exposure to a high altitude environment improved PImax and maximal oxygen uptake after returning to sea-level. |
