The present study aimed to investigate the effect of a 24-week aerobic + resistance training programs at moderate versus vigorous intensity on body composition, and the persistence of the changes after a 10-month free-living period, in young untrained adults. This report is based on a secondary analysis from the activating brown adipose tissue through exercise (ACTIBATE) single-center unblinded randomized controlled trial. A total of 144 young adults (65.6% women) aged 18-25 years were randomly allocated to three different groups: (a) aerobic + resistance exercise training program based on the international physical activity recommendations at vigorous intensity (Ex-Vigorous group), (b) at moderate intensity (Ex-Moderate group), and (c) control group (no exercise). Body composition outcomes were determined by a dual-energy X-ray absorptiometry scanner. Both Ex-Vigorous and Ex-Moderate decreased body weight, fat mass, and visceral adipose tissue mass in a similar manner (all p < .04). After a 10-month free-living period, these parameters returned to baseline levels in both exercise groups (all ps < .03). No differences between the exercise groups and the control group were noted in lean mass changes (all ps > .1). A 24-week aerobic + resistance training intervention based on the international physical activity recommendations was enough to improve body weight, fat mass, and visceral adipose tissue mass in untrained young adults, independently of the exercise intensity (moderate vs. vigorous).

中文翻译：

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中等与剧烈运动强度对未经训练的年轻人身体成分的影响：通过运动激活棕色脂肪组织 (ACTIBATE) 随机对照试验。

本研究旨在调查未受过训练的年轻人，为期 24 周的中等强度和高强度有氧 + 阻力训练计划对身体成分的影响，以及 10 个月的自由生活期后变化的持续性。本报告基于通过运动激活棕色脂肪组织（ACTIBATE）单中心非盲随机对照试验的二次分析。共有 144 名 18-25 岁的年轻人（65.6% 女性）被随机分配到三个不同的组：（a）基于国际体力活动建议的高强度有氧 + 阻力运动训练计划（Ex-Vigorous 组）， (b) 中等强度（前中等组），和 (c) 对照组（无运动）。身体成分结果由双能 X 射线吸收测量扫描仪确定。Ex-Vigorous 和 Ex-Moderate 均以类似的方式降低体重、脂肪量和内脏脂肪组织量（所有 p < .04）。经过 10 个月的自由生活期后，两个运动组的这些参数均恢复到基线水平（所有 ps < .03）。运动组和对照组之间的瘦体重变化没有差异（所有 ps > .1）。根据国际身体活动建议进行的 24 周有氧 + 阻力训练干预足以改善未经训练的年轻人的体重、脂肪量和内脏脂肪组织量，而与运动强度（中等与剧烈）无关。