有無力竭之阻力運動對於健康年輕男性的食慾及食物偏好影響

Abstract

背景：過去研究顯示，運動結合適當的飲食有助於預防肥胖及體重控制。運動除了可以達到能量消耗的效果外，還可能通過暫時性的食慾抑制作用，進而減少能量攝入。過往研究多著重於有氧運動或高強度間歇運動所產生的食慾調節反應，且發現當有氧運動達到一定強度與足夠持續時間會產生暫時性食慾抑制的效果。然而，目前阻力運動對於食慾調控的文獻甚少，且因阻力運動處方設計的多樣性，導致結果較不一致。目的：本研究欲探討在相同負荷強度及組間休息下，進行自主力竭與固定次數的阻力運動對健康年輕男性食慾及食物偏好的影響。方法：18位年輕健康男性 (年齡20-30歲)，進行三次隨機交叉試驗：(1) 力竭 (Repetition to Failure, F)；(2) 無力竭 (Non-Repetition to Failure, NF)； (3) 控制試驗 (Control condition, C)。阻力運動以自由重量 (free weight) 執行，執行動作次序為：槓鈴深蹲 (barbell squat)、槓鈴臥推 (bench press) 與六角槓硬舉 (hex bar deadlift)。運動強度為70% 1 RM (one-repetition maximum)，每項動作各執行三組，F試驗每組執行至力竭；NF試驗每組執行七下；C試驗靜坐休息。並於介入前、後立即、後30分鐘、後60分鐘與後90分鐘等五時間點測量受試者之主觀食慾、乳酸及飢餓素。隨後午餐提供隨意進食 (ad libitum)，以評估能量攝取。使用里茲食物偏好問卷評估運動後30分鐘與午餐進食前後之食物偏好。紀錄實驗前一天、實驗當天和實驗後一天的能量攝取量。所得數據將以混合線性模型 (linear-mixed model) 進行分析。結果：主觀食慾感受於運動後立即，F顯著低於NF及CON (p< 0.001)，且NF也顯著低於CON (p = 0.031)。飢餓素於運動後立即至運動後90分鐘，F顯著低於NF及CON (p < 0.05)。乳酸於運動後立即、運動後30分鐘、60分鐘，F顯著高於NF及CON (p < 0.001)，且NF於運動後立即及運動後30分鐘顯著高於CON (p < 0.05)。 F對高脂肪食物偏好顯著低於NF及CON (p < 0.05)。F對甜味食物偏好顯著高於CON (p < 0.05)。能量攝取在三組間則無顯著差異 (p > 0.05)。結論：本研究發現阻力運動會暫時性地抑制整體主觀食慾，並降低飢餓素水平。此效應因力竭而更加顯著，並與較高的血乳酸濃度和總訓練量相關。在食物偏好的影響上，力竭性阻力運動顯著減少對於高脂肪食物的偏好，且增加對甜味的偏好。然而，阻力運動並不會對能量攝取產生影響。未來還需進一步探討這種阻力運動處方對於食慾、食物偏好和能量攝取間的潛在機制以及長期影響。Introduction: Combining exercise with an appropriate diet helps prevent obesity and aids in weight control. Exercise not only promotes energy expenditure but also has the potential to temporarily suppress appetite, leading to a reduction in energy intake. Previous studies mainly focused on appetite regulation in aerobic or high- intensity interval exercise, suggesting that the sufficient duration and intensity of exercise result in temporary appetite suppression. However,little is known about the impact of resistance exercise on appetite control. Furthermore, the inconsistency of results can be attributed to the varied prescription designs of resistance training. Purpose: This study aimed to investigate the effects of resistance exercise, with and without failure, under equal loads and rest intervals on appetite and food preferences in healthy young men. Methods: Eighteen healthy young men (aged 20-30) completed three randomized crossover trials (F: repetition to failure; NF: non-repetition to failure; CON: control condition). Participants performed resistance exercise in the following order: barbell squat, bench press, hex bar deadlift. Each exercise was performed 3 sets with 70% 1RM (F: each set to failure; NF: 7 repetitions for each set). The control condition involved a quite resting. Subjective appetite perceptions, acylated ghrelin, and lactate were measured at pre-exercise, immediately, 30 minutes, 60 minutes, and 90 minutes post-exercise. An ad libitum meal was provided after lunch to assess energy intake. Food preferences were measured at 30 minutes, 90 minutes post-exercise, and after ad libitum meal using Leeds food preference questionnaire. Energy intake was recorded on the day before, during, and after the experiment. Data were analyzed using linear-mixed model. Results: Subjective appetite perceptions in the F were significantly lower immediately post-exercise compared to both the NF and CON (p< 0.001), and the NF also showed significantly lower subjective appetite perceptions immediately post-exercise the CON (p = 0.031). Acylated ghrelin concentration reduced in the F at immediately, 30 minutes, 60 minutes and 90 minutes post-exercise compared to both the NF and CON (p < 0.05). Lactate concentration increased in the F at immediately, 30 minutes, and 60 minutes post-exercise compared to both the NF and CON (p < 0.001), and higher lactate concentration was observed in the NF at immediately and 30 minutes post-exercise compared to the CON (p< 0.05). F showed a significantly lower preference for high fat food compared to both NF and CON (p < 0.05). Higher preference in sweet food was observed in the F compared to the CON (p < 0.05). However, there were no significant differences in energy intake among the three trials (p > 0.05). Conclusion: This study demonstrated that resistance exercise transiently suppresses overall subjective appetite and reduces ghrelin concentration. The effect is more significant with repetitions to failureand correlates with higher blood lactate concentrations and total training volume. Additionally, resistance exercise with repetitions to failure significantly reduces the preference for high-fat foods and increases the preference for sweet foods. However, resistance exercise doesn’t have an impact on energy intake. Further research is needed to explore the underlying mechanisms and long-term effects of resistance exercise prescription on appetite, food preferences, and energy intake.