<P> β - hydroxy β - methylbutyrate (HMB), a metabolite of leucine which is sold as a dietary supplement, has demonstrated efficacy in preventing the loss of muscle mass in several muscle wasting conditions in humans, particularly sarcopenia . A growing body of evidence supports the efficacy of HMB as a treatment for reducing, or even reversing, the loss of muscle mass, muscle function, and muscle strength in hypercatabolic disease states such as cancer cachexia; consequently, as of June 2016 it is recommended that both the prevention and treatment of sarcopenia and muscle wasting in general include supplementation with HMB, regular resistance exercise, and consumption of a high - protein diet . Based upon a meta - analysis of seven randomized controlled trials that was published in 2015, HMB supplementation has efficacy as a treatment for preserving lean muscle mass in older adults . More research is needed to determine the precise effects of HMB on muscle strength and function in this age group . </P> <P> Since the absence of muscle - building amino acids can contribute to muscle wasting (that which is torn down must be rebuilt with like material), amino acid therapy may be helpful for regenerating damaged or atrophied muscle tissue . The branched - chain amino acids or BCAAs (leucine, isoleucine, and valine) are critical to this process, in addition to lysine and other amino acids . </P> <P> In severe cases of muscular atrophy, the use of an anabolic steroid such as methandrostenolone may be administered to patients as a potential treatment . A novel class of drugs, called SARM (selective androgen receptor modulators) are being investigated with promising results . They would have fewer side - effects, while still promoting muscle and bone tissue growth and regeneration . These claims are, however, yet to be confirmed in larger clinical trials . </P> <P> One important rehabilitation tool for muscle atrophy includes the use of functional electrical stimulation to stimulate the muscles . This has seen a large amount of success in the rehabilitation of paraplegic patients . </P>

When muscles are immobilized as in a cast they undergo a decrease in size a change called