單次不同休息配置阻力運動對心臟自主神經調控與動脈硬度之影響

Abstract

目的：心血管疾病為全球重要死亡風險因子，自主神經系統異常和動脈硬度上升與心血管疾病風險上升有關，過去研究發現高強度急性阻力運動會產生動脈硬度上升的副作用，本次研究欲透過不同休息配置阻力運動，探討是否能夠改善阻力運動所造成的不良影響，同時觀察不同休息配置阻力運動心臟自主神經調控與動脈硬度的差異。方法：招募29位40-65歲健康受試者(19位女性10位男性，年齡50.4±7.9歲)，實驗使用交叉實驗設計，進行兩種不同休息配置的阻力運動，分別為：傳統配置與群組配置，傳統配置進行4組8下組間休息5分鐘，群組配置進行16組2下組間休息1分鐘，動作訓練強度為80% 1RM，訓練動作包含槓鈴胸推(chest press)、肱二頭肌彎舉(biceps curl)、膝伸展(knee extension)三個項目，不同實驗配置間隔至少72小時。所有受試者皆於運動前、運動後立即與運動後30分鐘量測心血管指標，包含：血乳酸濃度、血流動力學檢測、感壓敏感度、心跳變異性。實驗數據將進行ANOVA分析與t檢定，比較運動前後兩種配置之間是否有顯著差異，相關性測試透過Spearman相關性測試。結果：中老年族群在經過單次阻力運動，肱-踝脈波傳導速率(brachial-ankle pulse wave velocity, baPWV)上升並不顯著(傳統配置：1279.88±192.3上升為1295.73±225.39 m/s；群組配置：1314.55±248.23上升為1318.11±207.79 m/s)，其中群組訓練對於血乳酸濃度、血管硬度、血壓的上升較不顯著，同時群組訓練對自主神經的刺激較小，副交感神經指標RMSSD、HF衰退較少(p < .05)。結果發現休息狀態baPWV與心臟自主神經調控具有顯著負相關(r= -0.67, p < .05)，副交感神經活性越低的受試者動脈硬度越高。結論：透過80% 1 RM 組間休息1分鐘的群組配置不會造成急性阻力運動的負面效果，可能更適合作為中老年人建議阻力運動之處方。

Purpose: Cardiovascular disease is an important global risk factor for death, and autonomic nervous system abnormalities or arterial stiffness are associated with an increased risk of cardiovascular disease. Studies have found that high-intensity resistance exercise causes side effects of increased arterial stiffness. This study intends to adopt different rest intervals of resistance exercises to explore which sets can attendant the adverse effects of resistance exercise via cardiac autonomic regulation and arterial stiffness. Methods: Twenty-nine healthy participants (19 females and 10 males, aged: 50.4 ± 7.9yrs) were recruited, and the experiment used a cross-over experimental design to perform resistance exercise of two different rest intervals sets (traditional set vs. cluster set); Traditional set was performed with 4 sets of 8 reps with 5 minutes of rest between sets, whereas cluster set was performed with 16 sets of 2 reps with 1 minute of rest between sets. The intensity is set at 80% 1RM, using barbell chest press, biceps curl, and knee extension exercises. The experiment intervention of different configurations was separated for at least 72 hours. All cardiovascular indicators were measured before, immediately, and 30 minutes after exercise, including blood lactate concentration, hemodynamic monitoring, baroreflex sensitivity(BRS), and heart rate variability(HRV). Repeated measure 2-way ANOVA analysis and t-test were used to compare the difference between the two rest intervals on measured variables. The Spearman correlation test was also performed. Results: After a single bout of resistance exercise on the middle-aged and older adults, the increase in vascular stiffness is not significant (Traditional sets: 1279.88±192.3 increased to 1295.73±225.39 m/s; Cluster sets: 1314.55±248.23 increased to 1318.11±207.79 m/s). The cluster set protocol did not significantly increase blood lactic acid, vascular stiffness, and blood pressure among the two configurations. Moreover, the cluster set elicited lower sympathetic and parasympathetic activity such that RMSSD and HF declined less than traditional sets (p < .05). The correlation test indicated that baPWV was significantly negatively correlated with cardiac autonomic regulation (r= -0.67, p < .05). Participant with lower parasympathetic tone would have higher arterial stiffness. Conclusion: The 80% 1RM with 1 minute of rest between sets appears to introduce less negative effect following an acute bout of resistance exercise, and such configurations may be more suitable for the middle-aged and older population.