缺血預處理對蹲舉運動表現之影響

Abstract

目的：本研究旨在探討缺血預處理 (ischemic preconditioning, IPC) 對於具規律阻力訓練經驗者的平行蹲舉 (parallel squat) 運動表現之影響。方法：本研究共招募12名成年男性 (年齡，23 ± 2歲；身高，176 ± 7公分；體重，76 ± 15公斤；蹲舉最大肌力，125 ± 42公斤)。每位受試者需先進行2次控制處理 (CON)，然後，再依隨機交叉之方式接受LIPC處理 (local IPC，加壓220 mmHg) 與SHAM處理 (加壓20 mmHg)，其中LIPC與SHAM包含進行4個循環的5分鐘缺血與5分鐘再灌流。實驗處理結束後，受試者需在測力板上進行4組平行蹲舉測驗，負荷設定為60% 1 RM (repetition maximum, RM)，並於第4組蹲舉測驗中，要求受試者盡可能多地實施蹲舉運動至衰竭。結果：LIPC在蹲舉測驗時的反覆次數 (LIPC vs. SHAM vs. CON, 23 ± 5 vs. 20 ± 4 vs. 19 ± 4下, p = .001) 及運動量 (LIPC vs. SHAM vs. CON, 1627.2 ± 527.3 vs. 1456.7 ± 488.2 vs. 1341.3 ± 428.2公斤, p = .001)，均明顯高於其他實驗處理。在平均力量輸出、最大發力率與瞬時發力率方面，LIPC皆明顯高於CON (p< .05)。此外，在蹲舉測驗過程中的肌肉氧飽和度、血乳酸與運動強度自覺分數，在各實驗處理之間均無顯著差異。結論：LIPC能促進具有阻力訓練經驗者的蹲舉運動表現，然而，LIPC不會改變衰竭性蹲舉運動時的運動肌群血流量與氧飽和度。

Purpose: This study investigated the effect of ischemic preconditioning (IPC) on parallel squat performance in individuals with regular resistance training experiences. Methods: Twelve males were recruited [age, 23 ± 2 years; height, 176 ± 7 cm; body mass, 76 ± 15 kg; squat 1RM (repetition maximum), 125 ± 42 kg] in this study. All participants were required to conduct 2 control (CON) treatments, and then performed LIPC (local IPC, 220 mmHg) and SHAM (20 mmHg) treatments in randomized crossover design. The LIPC and SHAM included 4 cycles of 5-min ischemia and 5-min reperfusion. During the squat test, participants performed 4 sets of parallel squat at 60% 1RM on the force platform. At the fourth set, participants were asked to perform as many repetitions as possible until exhaustion. Results: The number of repetitions (LIPC vs. SHAM vs. CON, 23 ± 5 vs. 20 ± 4 vs. 19 ± 4 reps, p = .001) and exercise volume (LIPC vs. SHAM vs. CON, 1627 ± 527 vs. 1457 ± 488 vs. 1341 ± 428 kg, p = .001) in LIPC were significantly greater than the others. The average force, maximal and instantaneous rate of force development in LIPC were significantly higher than those in CON (p< .05). There were no significant differences in tissue saturation index, blood lactate concentration, and rating of perceived exertion during squat test among treatments. Conclusion: LIPC might improve the squat performance in resistance-trained individuals, however, LIPC would not change the blood flow and muscular oxygenation during exhaustive squat exercise.