The INVEST in Bone Health Trial reveals critical insights into the interplay between weight loss and musculoskeletal health, particularly through the lens of resistance training (RT) and weighted vest use. In this secondary analysis, 150 participants aged approximately 66 years were randomized into three groups: weight loss (WL), WL plus resistance training (WL + RT), and WL plus weighted vest (WL + VEST). The study utilized computed tomography (CT) and dual-energy x-ray absorptiometry (DXA) to assess changes in muscle area, density, and body composition over 12 months.

Significantly, all groups achieved comparable weight loss of around 10%. However, the WL + RT group exhibited notable improvements in mid-thigh muscle cross-sectional area (CSA) by 0.5% and muscle density by 3.7%-5.9% (p < .03), alongside reductions in intermuscular adipose tissue (IMAT) by 20%-22% and fat mass by 22%-26.8%. In contrast, the WL + VEST group showed only a trend toward muscle preservation and density improvement (4.2%, p = 0.08) without significant differences in other measures. The analysis also revealed a negative correlation between weight loss and muscle CSA, indicating that while weight loss improves muscle quality, it may also lead to reductions in muscle quantity.

These findings emphasize the need to integrate progressive resistance training as a critical component in weight management strategies aimed at preserving musculoskeletal health. The results suggest that while weight loss is beneficial, the concurrent application of RT can mitigate muscle loss, thereby enhancing the therapeutic potential of weight management interventions in older adults. This study shifts the focus toward optimizing resistance training protocols in clinical settings, potentially influencing future guidelines for weight loss programs targeting aging populations.

Source: academic.oup.com