Resistance Training in Hypoxia as a New Therapeutic Modality for Sarcopenia—A Narrative Review

Abstract

Hypoxic training is believed to be generally useful for improving exercise performance in various athletes. Nowadays, exercise intervention in hypoxia is recognized as a new therapeutic modality for health promotion and disease prevention or treatment based on the lower mortality and prevalence of people living in high-altitude environments than those living in low-altitude environments. Recently, resistance training in hypoxia (RTH), a new therapeutic modality combining hypoxia and resistance exercise, has been attempted to improve muscle hypertrophy and muscle function. RTH is known to induce greater muscle size, lean mass, increased muscle strength and endurance, bodily function, and angiogenesis of skeletal muscles than traditional resistance exercise. Therefore, we examined previous studies to understand the clinical and physiological aspects of sarcopenia and RTH for muscular function and hypertrophy. However, few investigations have examined the combined effects of hypoxic stress and resistance exercise, and as such, it is difficult to make recommendations for implementing universal RTH programs for sarcopenia based on current understanding. It should also be acknowledged that a number of mechanisms proposed to facilitate the augmented response to RTH remain poorly understood, particularly the role of metabolic, hormonal, and intracellular signaling pathways. Further RTH intervention studies considering various exercise parameters (e.g., load, recovery time between sets, hypoxic dose, and intervention period) are strongly recommended to reinforce knowledge about the adaptational processes and the effects of this type of resistance training for sarcopenia in older people.

Blood Flow Restriction Enhances Rehabilitation and Return to Sport: The Paradox of Proximal Performance

“…[43][44][45] These responses have been observed to facilitate postexercise increases in anabolic signaling (centrally and locally) as well as significantly influence metabolic adaptations to exercise training. [46][47][48] In addition to the production of metabolites such as lactate and CO 2 into circulation during strenuous exercise, skeletal muscle has also been observed to release a host of myokines that have the capacity to act in an autocrine, paracrine, and endocrine manner. [49][50][51] Cumulatively, it is hypothesized that immediately following the occlusive stimulus, the release of these effectors into circulation may stimulate anabolism (for muscle, bone, and connective tissue) locally as well as systemically.…”

“…60 Previous observations also suggest that the response of bone to chronic exercise is potentially interlinked with skeletal muscle with regards to mechanical, systemic, and local signaling factors. [44][45][46] Relatedly, myokines secreted from muscle during exercise in an intensity/stress dependent manner are known to act on bone metabolism in either proformation or resorption capacities. 51,[61][62][63][64] In addition, both systemic and muscle-derived IGFs and fibroblast growth factors are also known to act directly at the muscleebone interface.…”

Effect of hypoxic conditioning on functional fitness, balance and fear of falling in healthy older adults: a randomized controlled trial

“…Additionally, in CON group which did not perform any type of strength training, an increase in fat mass and a decrease in lean body mass were observed. Sarcopenia and loss of muscle strength during aging cause a decrease in physical fitness, functional capability, and balance ability [15]. Strength training has been consistently shown as an effective measure to mitigate muscle weakness, physical frailty, and functional capacity [7,32].…”

Scoping review protocol on nonpharmacological interventions for possible sarcopenia or sarcopenia in community-dwelling older adults

“…Among them, the first two approaches in independent or joint intervention are usual. The modalities of physical activity described in the literature are numerous [30][31][32][33][34] and different types of exercise can stimulate variable, but specific, responses in muscle functions [35]. However, there were discrepancies in the selection and combination of exercise modes, exercise intensity, total repetitions, rest periods, training dose, regularity and progression among different studies.…”