不同時段從事單次有氧運動對中年婦女二十四小時動態血壓之影響

Time-of-day effect of acute aerobic exercise on 24 hours ambulatory blood pressure in middle-aged women

緒論：臨床上，運動是降低血壓和心血管疾病危險因子的非藥理學治療方法，運動時宜 (exercise timing) 則可能有助於讓運動後產出更有效的降血壓結果。本研究主要目的在比較不同時段從事單次有氧運動對中年婦女24小時動態血壓 (ambulatory blood pressure, ABP) 之差異情形。方法：招募15名中年婦女 (45.40 ± 5.40歲) 各接受三次實驗處理，分別是以60% 儲備心跳率 (heart rate reserve) 之運動強度在不同的時間 (早上06:30和下午16:30) 從事30分鐘的有氧運動，以及靜坐30分鐘不運動的模擬控制處理，各個實驗處理之順序採隨機方式實施，且於每個實驗處理後配戴24小時ABP監測儀，監測其24小時ABP和心跳率之變異情形。以重複量數變異數分析 (repeated measure analysis of variance)，考驗不同時段從事單次有氧運動後24小時ABP和心跳率之變異情形。本研究顯著水準訂為α = .05。結果：下午時段從事單次有氧運動後的平均24小時收縮壓 (systolic blood pressure, SBP: 108.87 ± 10.76, p < .05)、舒張壓 (diabolic blood pressure, DBP: 70.73 ± 8.36, p < .05)、平均動脈壓 (mean arterial pressure, MAP: 84.53 ± 8.74, p < .05)、白天的DBP (72.33 ± 8.73, p < .05) 和 MAP (84.67 ± 10.77, p < .05) 均顯著低於早上從事單次有氧運動 (SBP: 113.07 ± 12.61, DBP: 75.33 ± 10.29, MAP: 87.33 ± 10.24) 及不運動的模擬控制條件 (SBP: 113.47 ± 13.50, DBP: 73.33 ± 8.76, MAP: 87.53 ± 10.01)；且下午從事單次有氧運動後，SBP 可持續降低2小時。然而，若將潛在高血壓受試者剔除，趨勢即不顯著。三種不同實驗處理後的24小時心跳變異情形則無顯著差異。結論：下午時段從事單次有氧運動可以顯著的降低24小時ABP和晨間血壓的上升，這可能有助於減少腦血管和心血管事件的發生機率。因此，對於血壓的管理，除了考量運動處方的要素之外，運動時間的選擇亦是一項相當重要的要素。

Introduction: Clinically, exercise is a nonpharmacological treatment for lowering blood pressure and reducing the risk of cardiovascular disease; however, the timing of exercise may contribute to more effective results following the exercise bout. The purpose of this study was to compare the effect of acute aerobic exercise varies with time of day on 24-h ambulatory blood pressure (ABP) in middle-aged women. Methods: fifteen middle-aged women (45.40 ± 5.40 years) volunteered for the study. Participants completed three randomly assigned conditions: a nonexercise control trail, and 30 min of aerobic exercise at different time of day (06:30 a.m. vs. 16:30 p.m.), with the mean exercise intensity at 60% of heart rate reserve. After all three sessions, participants underwent 24-h ABP and heart rate monitoring with an automated ABP device. A repeated measure analysis of variance (ANOVA) was be used to assess the effect of acute aerobic exercise varies with time of day on 24-h ABP and heart rate. Statistical significance was delimited at α = .05. Results: significantly lower post-exercise reduction were evident at 16:30 p.m. for 24-h systolic blood pressure (SBP: 108.87 ± 10.76, p < .05), 24-h diabolic blood pressure (DBP: 70.73 ± 8.36, p < .05), 24-h mean arterial pressure (MAP: 84.53 ± 8.74, p < .05), daytime DBP (72.33 ± 8.73, p < .05) and MAP (84.67 ± 10.77, p < .05) compared to after 06:30 a.m. exercise (SBP: 113.07 ± 12.61, DBP: 75.33 ± 10.29, MAP: 87.33 ± 10.24) and nonexercise control condition (SBP: 113.47 ± 13.50, DBP: 73.33 ± 8.76, MAP: 87.53 ± 10.01). SBP reduced for 2 hours after acute aerobic exercise in the afternoon. However, if the prehypertension subjects excluded, the trend that is no significant. There was no significant difference in the heart rate variability among three conditions. Conclusions: we conclude that acute aerobic exercise in the afternoon can significantly reduces 24-h ABP and morning surge in blood pressure, which can decrease the incidence of cerebrovascular and cardiovascular events. In addition to exercise prescription components, the scheduling of exercise is also important in the management of blood pressure.