不同阻力運動強度對健康男性食慾之影響

Abstract

前言：生活型態的改變和高熱量的飲食，造成能量失衡和身體質量上升。食慾與能量平衡有著密不可分的關係，其影響因素有身體活動和食慾荷爾蒙。運動對於體重管理是相當重要的手段之一，亦可以降低罹患代謝、心血管、癌症等疾病的風險。過往研究多為單次有氧運動介入或單次有氧與阻力運動相互比較對食慾之影響，尚無研究觀察單次不同強度阻力運動介入後食慾之變化。目的：探討不同強度阻力運動對健康男性食慾及相關荷爾蒙的影響。方法：招募11名健康男性作為受試者，以隨機交叉設計進行控制介入、低強度介入 (45% 8RM) 和高強度介入 (85% 8RM)，共三次試驗，每次試驗間隔一週。受試者使用史密斯機執行四項阻力運動動作，包含深蹲、站姿划船、臥推與羅馬尼亞硬舉。試驗過程依照標準流程測量身體組成、食慾荷爾蒙、乳酸以及食慾視覺類比量表。所得結果以重複量數二因子變異數分析進行統計分析。結果：食慾視覺量表中飢餓感在高強度與低強度介入後30分和60分顯著上升 (高強度：介入前3.93 ± 0.35 cm、介入後30分5.53 ± 0.95 cm、介入後60分6.66 ± 0.29 cm；低強度：介入前 4.34 ± 0.41 cm、介入後30分5.75 ± 0.27 cm、介入後60分6.09 ± 0.48 cm；p< .05)。其他飽足感、滿腹感與預期進食阻力運動介入後皆未達顯著水準。高強度與低強度兩次試驗的乳酸濃度在運動介入後立即的時間點並無顯著差異，但顯著高於控制介入 (高強度：12.32 ± 1.03mmol/L, 低強度：12 ± 1.05mmol/L, 控制組：1.62 ± 0.09mmol/L; p < .05)。兩種強度的PYY濃度在介入後立即顯著上升 (高強度：介入前12.46 ± 1.4pg/ml vs 介入後立即17.42 ± 2.7pg/ml；低強度：介入前10.63 ± 1.29pg/ml vs介入後立即17.09 ± 1.8pg/ml ; p < .05)。飢餓素不同介入下及介入前後也無顯著差異 (p < .05)。高強度與低強度產生之乳酸與飢餓素呈中度負相關 (高強度: r = -0.325, 低強度: r = -0.448, p < .05)。結論：單次等訓練量不同強度阻力運動後可知訓練量是影響主觀食慾和飢餓素的主要因子，以及乳酸濃度上升可能會抑制飢餓素進而影響主觀食慾。Introduction: Changing of lifestyle and high calorie diet could lead to energy unbalance and body mass increasing. Appetite, highly related to energy balance, is mediated by physical activity and appetite hormones. Regular exercise is one of the most important weight-managing methods to lower the risk of metabolism, cardiovascular disease and cancer. Previous studies mostly focused on the effect of acute aerobic exercise on appetite, or the comparison between acute aerobic and resistance exercise. However, there is lack of research examining the change of appetite after different-intensity resistance exercise. Purpose: This study investigated the effect of resistance exercise with different intensity on appetite and appetite hormones in healthy men. Methods: Eleven healthy men were recruited to complete three trials in randomized crossover design: including low load (45% 8RM), high load (85% 8RM) resistance exercise and resting for the control condition. Participants performed four exercise, including Romanian dead lift, bench press, squat and stand row on Smith machine. Every trial was executed the same standard procedure of measuring body composition index, lactate, appetite visual scale and appetite hormones with at least seven-day interval. The obtained data were statistically proceeded by two-way repeated measures ANOVA analysis. Results: Significant increase of hunger ratings was observed at both thirty and sixty minutes after high and low intensity intervention resistance exercise trial. (High: pre 3.93 ± 0.35 cm, post30 5.53 ± 0.95 cm, post60 6.66 ± 0.29 cm; Low: pre 4.34 ± 0.41 cm, post30 5.75 ± 0.27 cm, post60 6.66 ± 0.29 cm; p< .05). There was no significant difference in other appetite rating, nor was no significant difference on lactate concentration between high and low intensity trial at immediately after exercise, but both exercise trials were significantly higher than control trial (High: 12.32 ± 1.03mmol/L, Low: 12 ± 1.05mmol/L, Con: 1.62 ± 0.09mmol/L; p < .05). PYY concentration significantly raised after both exercises in postexercise (High: pre 12.46 ± 1.4pg/ml vs post0 17.42 ± 2.7pg/ml；Low: pre 10.63 ± 1.29pg/ml vs post0 17.09 ± 1.8pg/ml ; p< .05) Ghrelin concentration was unchanged with exercise and intensity (p < .05). There was a negative and moderate significant correlation between lactate and ghrelin for high and low intensity (High: r = -0.325, Low: r = -0.448, p < .05). Conclusions: After single bout of equal-volume resistance exercise, we could conclude that volume and lactate concentration are the two main factor influencing appetite and ghrelin in healthy young men.