Osteosarcopenia is characterized by a progressive decline in muscle function and bone strength and associated with muscle fat accumulation. This study aimed to determine the effect of long-term high intensity resistance training (HIRT) on thigh muscle fat infiltration in older men with osteosarcopenia. Forty-three community-dwelling men (72 years and older) were randomly assigned to either an exercise group (EG, n = 21) or an inactive control group (CG, n = 22). EG participants performed a supervised single-set exercise training with high effort two times per week. Participants of both groups were individually provided with dietary protein to reach a cumulative intake of 1.5–1.6 g/kg/day or 1.2–1.3 g/kg/day (EG/CG), respectively, and Up to 10,000 IE/week of Vitamin-D were supplemented in participants with 25 OH Vitamin-D 3 levels below 100 nmol/l. Magnetic resonance (MR) imaging was performed to determine muscle and adipose tissue volume and fat fraction of the thigh. At baseline, there were no significant differences between the two groups. After 16 month,, there were significant training effects of 15% (p = 0.004) on intermuscular adipose tissue (IMAT) volume, which increased in the CG (p = 0.012) and was stable in the EG. In parallel, fat fraction within the deep fascia of the thigh (Baseline, EG: 18.2 vs CG: 15.5, p = 0.16) significantly differed between the groups (Changes, EG: 0.77% vs. CG: 7.7%, p = 0.009). The study confirms the role of fat infiltration of the muscles as an advanced imaging marker in osteosarcopenia and the favorable effects of HIRT on adipose tissue volume of the thigh, in men with osteosarcopenia.

骨肌减少症的特点是肌肉功能和骨强度逐渐下降，并与肌肉脂肪堆积有关。本研究旨在确定长期高强度阻力训练 (HIRT) 对患有骨肌减少症的老年男性大腿肌肉脂肪浸润的影响。43 名社区居住男性（72 岁及以上）被随机分配到运动组（EG，n  = 21）或不运动对照组（CG，n  = 22）。EG 参与者每周进行两次高强度监督单组运动训练。两组参与者均单独摄入膳食蛋白质，分别达到 1.5–1.6 g/kg/天或 1.2–1.3 g/kg/天 (EG/CG) 的累积摄入量，以及高达 10,000 IE/周的维生素参与者补充的 25 OH 维生素 D 3 水平低于 100 nmol/l。进行磁共振（MR）成像以确定大腿的肌肉和脂肪组织体积以及脂肪分数。基线时，两组之间没有显着差异。16 个月后，肌间脂肪组织 (IMAT) 体积显着增加 15% ( p  = 0.004)，在 CG 中增加 ( p  = 0.012)，在 EG 中保持稳定。与此同时，大腿深筋膜内的脂肪分数（基线，EG：18.2 vs. CG：15.5，p  = 0.16）在各组之间存在显着差异（变化，EG：0.77% vs. CG：7.7%，p  = 0.009） 。该研究证实了肌肉脂肪浸润作为骨肌减少症高级成像标志物的作用，以及 HIRT 对骨肌减少症男性大腿脂肪组织体积的有利影响。