Frawley Kendall, Greenwald Gabrielle, Rogers Rebecca R, Petrella John K, Marshall Mallory R
Department of Kinesiology, Samford University, Birmingham, AL, USA.
Int J Exerc Sci. 2018 Jun 1;11(2):827-833. doi: 10.70252/CQMF3722. eCollection 2018.
Prior research has demonstrated that the percentage of fuel utilization contributed by CHO compared to fat rises with an increase in exercise intensity. The role of food intake prior to exercise has been well studied and fasting prior to exercise generally increases reliance on fat as fuel. However, data on the role of fasting prior to resistance exercise is limited. Therefore, the purpose of this study was to assess the effects of one bout of resistance training in a fasted state compared to ingestion of standardized meal on fat and carbohydrate utilization. Twelve female (n = 12, age = 20.1 ± 0.79 yrs, height = 67.0 ± 2.63 in, weight = 143 ± 21.8 lbs) NCAA Division 1 athletes participated in the study. Each participant completed one 10 hour fasted resistance training session and one postprandial resistance training session. The respiratory exchange ratio (RER) and METs were measured using a Cosmed K4b portable metabolic cart (Cosmed, Rome, Italy) and heart rate was measured by a Polar H1 heart rate monitor. Participants consumed the prescribed food, waited 15 minutes, and then completed three sets of five repetitions of bench press, back squat, and military press at 60% of their 1-repetition maximum. The mean fasted RER was significantly lower than postprandial for back squat (p=0.01) and military press (p=0.02), but not bench press (p=0.19). There was no difference in METs, RPE, or HR between fasted and postprandial trials for any exercise. Results suggest that fasted resistance exercise relies more heavily on fat metabolism than carbohydrate.
先前的研究表明，与脂肪相比，碳水化合物（CHO）在燃料利用中所占的百分比会随着运动强度的增加而上升。运动前食物摄入的作用已得到充分研究，运动前禁食通常会增加对脂肪作为燃料的依赖。然而，关于抗阻运动前禁食作用的数据有限。因此，本研究的目的是评估与摄入标准化餐食相比，在禁食状态下进行一轮抗阻训练对脂肪和碳水化合物利用的影响。12名美国全国大学体育协会（NCAA）一级联赛的女运动员（n = 12，年龄 = 20.1 ± 0.79岁，身高 = 67.0 ± 2.63英寸，体重 = 143 ± 21.8磅）参与了该研究。每位参与者完成了一次10小时的禁食抗阻训练课程和一次餐后抗阻训练课程。使用Cosmed K4b便携式代谢分析仪（Cosmed，罗马，意大利）测量呼吸交换率（RER）和代谢当量（METs），并通过Polar H1心率监测仪测量心率。参与者食用规定的食物，等待15分钟，然后以其一次重复最大值的60%完成三组，每组五次的卧推、深蹲和推举动作。深蹲（p = 0.01）和推举（p = 0.02）的平均禁食RER显著低于餐后，但卧推（p = 0.19）并非如此。在任何运动的禁食和餐后试验之间，METs、主观用力程度（RPE）或心率均无差异。结果表明，禁食抗阻运动比碳水化合物更依赖脂肪代谢。
