Department of Biomedical Sciences, University of Sassari, Viale S. Pietro 43/b, 07100, Sassari, Italy.
Unit of Endocrinology, Nutritional and Metabolic Disorders, AOU Sassari, Sassari, Italy.
Eur J Appl Physiol. 2022 Jan;122(1):29-70. doi: 10.1007/s00421-021-04802-5. Epub 2021 Sep 22.
To explore sex-based differences in energy substrate utilization during moderate-intensity aerobic exercise; to identify the underpinning candidate physiological mechanisms.
Three databases were searched from inception to August 2020. Pertinent studies quantifying the utilization of substrates during moderate aerobic exercise in healthy men and reproductive-age women were considered. Studies conducted on sedentary/recreationally active and athletic populations were included and analyzed separately.
Thirty-five studies entered the meta-analysis (21 in sedentary/recreationally active, 14 in athletic populations). Compared to women, the respiratory exchange ratio was significantly higher both in sedentary (mean difference, MD: + 0.03; p < 0.00001) and athletic men (MD: + 0.02; p < 0.0001). Greater carbohydrate oxidation was observed both in sedentary (standardized MD, SMD: 0.53; p = 0.006) and athletic men (SMD: 1.24; p < 0.00001). Regarding lipid substrates, sedentary men oxidized less fat than women (SMD: - 0.77; p = 0.0002), while no sex-based differences in fat oxidation were observed in athletes (SMD: 0.06; p = 0.77). Paucity of data prevented robust meta-analyses for protein sources. Sex hormones and different adrenergic activation were the most cited mechanisms to discuss sex-based differences.
Meta-analyses confirmed that men display greater reliance on carbohydrates while women rely more on lipids to sustain moderate aerobic exercise. The latter finding was not confirmed in athletes, a novel aspect of the present study. Mechanistically driven research is needed to further dissect the physiological underpinnings of sex differences in substrate utilization during aerobic exercise, especially for proteins, which are still less investigated than other substrates.
探讨中等强度有氧运动中能量底物利用的性别差异；确定潜在的候选生理机制。
从创建到 2020 年 8 月，对三个数据库进行了搜索。考虑了定量测量健康男性和生殖年龄女性在中等有氧运动中利用底物的相关研究。纳入并分析了久坐/休闲活跃和竞技人群的研究。
35 项研究纳入荟萃分析（21 项在久坐/休闲活跃人群中，14 项在竞技人群中）。与女性相比，久坐男性（平均差异，MD：+0.03；p<0.00001）和竞技男性（MD：+0.02；p<0.0001）的呼吸交换率显著更高。久坐（标准化 MD，SMD：0.53；p=0.006）和竞技男性（SMD：1.24；p<0.00001）中观察到更多的碳水化合物氧化。关于脂质底物，久坐男性比女性氧化的脂肪更少（SMD：-0.77；p=0.0002），而运动员中没有观察到性别对脂肪氧化的差异（SMD：0.06；p=0.77）。数据匮乏，无法进行稳健的荟萃分析来研究蛋白质来源。性激素和不同的肾上腺素能激活是讨论性别差异的最常被引用的机制。
荟萃分析证实，男性在维持中等有氧运动时更依赖碳水化合物，而女性则更多地依赖脂肪。这一发现在运动员中没有得到证实，这是本研究的一个新方面。需要进行机制驱动的研究，以进一步剖析有氧运动中性别差异在底物利用方面的生理基础，特别是对于蛋白质，其研究仍不如其他底物广泛。
