緒論：發展可模擬高地訓練時的訓練模式對教練、運動員以及相關運科人員未來在訓練課表擬定上將有更多的選擇參考。本研究目的為探討短期低氧訓練面罩介入對鐵人三項選手呼吸肌肌力及自行車運動表現的影響。方法：13位鐵人三項運動員，以身高、體重及最大攝氧量(maximal oxygen consumption, VO_2max)之數值進行配對，分為控制組(168.3 ± 2.2公分、63.2 ± 2.7公斤、51.2 ± 4.0 ml/kg/min, n=5)及面罩組(169.0 ± 2.6公分、63.4 ± 2.5公斤、52.2 ± 3.3 ml/kg/min, n=8)。以單盲方式穿戴低氧訓練面罩，並合併四週的自行車訓練，訓練前後均接受身體組成、最大呼吸壓力、功率閾值 (functional threshold power, FTP)、VO_2max測量，並於訓練期間填寫三日身體活動量表及運動自覺量表 (RPE)。結果：運動訓練明顯提高兩組之最大攝氧量。低氧訓練面罩介入合併自行車訓練後，面罩組顯著增加最大呼氣壓力，但兩組之FTP則無明顯差異。此外，面罩組在四週介入後，在降低脂肪率及增加肌肉量明顯優於控制組。結論：四週自行車訓練明顯提高鐵人三項運動員之最大攝氧量，而合併低氧訓練面罩介入可進一步產生增加最大呼氣壓力與改善身體組成之效果。

Introduction: Developing a practical training model that mimics altitude training will provide more information for coaches, athletes and sport sciences team in designing a more effective training schedule. This study was conducted to explore the short-term wearing a hypoxic training mask effect on respiratory muscle strength and cycling performance in triathletes. Methods: A total of 13 triathletes were recruited. The matched pair grouping method was adopted to divide the triathletes by their height, body weight and maximal oxygen consumption (VO_2max) into a control group (168.3 ± 2.2 cm, 63.2 ± 2.7 kg, 51.2 ± 4.0 ml/kg/min, n=5) and training mask group (169.0 ± 2.6 cm, 63.4 ± 2.5 kg, 52.2 ± 3.3 ml/kg/min, n=8). A single-blind method was employed to administer a 4-week intervention, in which the triathletes were asked to wear a training mask while training. The triathlete's body composition, maximal respiratory muscle pressure, functional threshold power (FTP), and VO_2max were measured before and after the intervention. In addition, athletes were asked to fill out a three-day physical activity log and perceived exertion rating log during the intervention. Results: After the intervention, the VO_2max was significantly enhanced in both groups. The training mask group showed significantly higher post-training maximal expiratory pressure (PEmax) than pre-training after 4-week intervention. However, the FTP of the training mask and control groups were not different. The percent changes in fat mass and muscle mass for the training mask group were more favorable than those for the control group, attaining significant between-group differences (p = .039 and .014, respectively). Conclusion: Our study demonstrates that the four weeks exercise training significantly enhanced maximal oxygen consumption in these young triathletes. In addition, exercise training combined with the hypoxic training mask could further generate improvement in maximal expiratory pressure and body composition.