High-load resistance training and FSHD: harmful mixture or a silver bullet combination?

Facioscapulohumeral muscular dystrophy (FSHD) is a progressive neuromuscular disorder characterized by asymmetric loss of muscle mass and strength, as well as fatty infiltration, inflammation, oxidative stress, and fibrosis. Unfortunately, as the disease progresses, these features can lead to the loss of mobility and independence. High-load resistance training (RT) is a well-established therapeutic strategy for increasing muscle mass and strength, and emerging evidence suggests it may also attenuate fatty infiltration, inflammation, oxidative stress, and fibrosis in other populations. Despite this therapeutic potential, high-load RT has long been approached with caution in FSHD, and current recommendations largely discourage its use. In this review, we critically examine the historical and scientific basis for this dogma and find that it rests on a small number of poorly substantiated and largely unreplicated studies. We further show that the limited RT trials conducted in individuals with FSHD have consistently reported good tolerability and, in several cases, moderate improvements in strength and function. Critically, no study to date has implemented a true high-load RT protocol alongside validated markers of muscle damage, a design that accounts for the asymmetry of the disease, and imaging that is sensitive enough to detect disease-modifying effects (e.g., MRI). We argue that the current consensus against high-load RT in FSHD reflects an absence of evidence rather than evidence of no benefit. Thus, we hope this narrative review encourages the FSHD community to revisit fundamental questions about the safety and therapeutic potential of high-load RT, and to create practical guidelines based on rigorous studies.