不同劑量缺血預處理對蹲舉表現之影響

Abstract

目的：探討不同劑量缺血預處理 (ischemic preconditioning, IPC) 對於阻力訓練經驗者蹲舉運動表現之影響。方法：本研究共招募12名成年男性。每位受試者先進行控制處理 (CON)，接著以隨機交叉平衡次序方式，分別進行三種實驗處理，包括40分鐘 (IPC40)、20分鐘 (IPC20) 和偽處理 (SHAM)，其中IPC40為交替加壓雙側大腿220 mmHg，進行4循環5分鐘的缺血與5分鐘的再灌注，而IPC20則為2個循環，SHAM則為20 mmHg。實驗處理結束後，受試者須進行3組70%1RM的蹲舉至衰竭測驗。蹲舉過程中，計算反覆次數和訓練量，以及使用測力板和位移計蒐集相關動力學指標，並以近紅外線光譜儀檢測肌肉氧飽和度。結果：蹲舉時的反覆次數、訓練量、動力學指標和肌肉氧飽和度，在4種處理之間均無顯著差異。不過，在最大速度方面，IPC40、SHAM與CON的第二、三組均顯著低於第一組 (第一組 vs. 第二組 vs. 第三組, IPC40: 0.96 ± 0.12 vs. 0.91 ± 0.13 vs. 0.89 ± 0.11 m/s, SHAM: 0.95 ± 0.09 vs. 0.89 ± 0.10 vs. 0.86 ± 0.10 m/s, CON: 0.98 ± 0.12 vs. 0.89 ± 0.12 vs. 0.84 ± 0.12 m/s, p< .05)，而IPC20則在各組之間無顯著差異。在含氧血紅素變化率方面，IPC20與CON的第二、三組顯著高於第一組 (第一組 vs. 第二組 vs. 第三組, IPC40: -17.2 ± 7.9 vs. -14.7 ± 7.4 vs. -14.2 ± 7.7 µmol·L-1, CON: -17.5 ± 5.6 vs. -15.2 ± 5.3 vs. -14.4 ± 5.5 µmol·L-1, p < .05)，SHAM的第二組顯著高於第一組 (第一組 vs. 第二組, -15.8 ± 5.8 vs. -13.6 ± 6.7 µmol·L-1, p < .05)，而IPC40則在各組之間無顯著差異。結論：不同劑量的IPC，均無法改善蹲舉運動的反覆次數和訓練量。不過，IPC20似乎具有延緩最大速度流失的效果，而IPC40則可維持含氧血紅素的解離。Purpose: To investigate the effect of different doses of ischemic preconditioning (IPC) on squat performance in experienced resistance training participants. Methods: 12 males were required to complete a control trial (CON), and then performed 3 treatments in a randomized crossover design, including IPC40 (4-cycles × 5-min 220 mmHg bilateral thighs occlusion), IPC20 (2-cycles), and SHAM (20 mmHg). Participants performed 3 sets of squats with 70% of 1RM until concentric failure after each treatment. During the squat, the number of repetitions and training volume were measured. Dynamic variables were collected by force platform and linear displacement transducer. Changes in muscle oxygenation were monitored by near-infrared spectroscopy. Results: No significant differences were found in the number of repetitions, training volume, dynamic variables, and changes in muscle oxygenation among the 4 treatments during the squat. However, the maximum velocity at the 2nd and 3rd set in the IPC40, SHAM, and CON were significantly lower than the 1st set. (1st vs. 2nd vs. 3rd, IPC40: 0.96 ± 0.12 vs. 0.91 ± 0.13 vs. 0.89 ± 0.11 m/s, SHAM: 0.95 ± 0.09 vs. 0.89 ± 0.10 vs. 0.86 ± 0.10 m/s, CON: 0.98 ± 0.12 vs. 0.89 ± 0.12 vs. 0.84 ± 0.12 m/s, p< .05), whereas there were no significantly different among the 3 sets in the IPC20. The change in oxyhemoglobin at the 2nd and 3rd set in the IPC20 and CON were significantly higher than the 1st set (1st vs. 2nd vs. 3rd, IPC40: -17.2 ± 7.9 vs. -14.7 ± 7.4 vs. -14.2 ± 7.7 µmol·L-1, CON: -17.5 ± 5.6 vs. -15.2 ± 5.3 vs. -14.4 ± 5.5 µmol·L-1, p < .05), and the 2nd set was significantly higher than the 1st set in the SHAM (1st vs. 2nd, -15.8 ± 5.8 vs. -13.6 ± 6.7 µmol·L-1, p < .05), whereas there were no significantly different among the 3 sets in the IPC40. Conclusion: Different doses of IPC could not improve squat repetitions and volume; however, IPC20 might prevent the decline in maximal squat velocity, while IPC40 might maintain the dissociation of oxyhemoglobin.