Nutrition and physical activity in the prevention and treatment of sarcopenia: systematic review

Abstract

SummaryThis systematic review summarizes the effect of combined exercise and nutrition intervention on muscle mass and muscle function. A total of 37 RCTs were identified. Results indicate that physical exercise has a positive impact on muscle mass and muscle function in subjects aged 65 years and older. However, any interactive effect of dietary supplementation appears to be limited.IntroductionIn 2013, Denison et al. conducted a systematic review including 17 randomized controlled trials (RCTs) to explore the effect of combined exercise and nutrition intervention to improve muscle mass, muscle strength, or physical performance in older people. They concluded that further studies were needed to provide evidence upon which public health and clinical recommendations could be based. The purpose of the present work was to update the prior systematic review and include studies published up to October 2015.MethodsUsing the electronic databases MEDLINE and EMBASE, we identified RCTs which assessed the combined effect of exercise training and nutritional supplementation on muscle strength, muscle mass, or physical performance in subjects aged 60 years and over. Study selection and data extraction were performed by two independent reviewers.ResultsThe search strategy identified 21 additional RCTs giving a total of 37 RCTs. Studies were heterogeneous in terms of protocols for physical exercise and dietary supplementation (proteins, essential amino acids, creatine, β-hydroxy-β-methylbuthyrate, vitamin D, multi-nutrients, or other). In 79% of the studies (27/34 RCTs), muscle mass increased with exercise but an additional effect of nutrition was only found in 8 RCTs (23.5%). Muscle strength increased in 82.8% of the studies (29/35 RCTs) following exercise intervention, and dietary supplementation showed additional benefits in only a small number of studies (8/35 RCTS, 22.8%). Finally, the majority of studies showed an increase of physical performance following exercise intervention (26/28 RCTs, 92.8%) but interaction with nutrition supplementation was only found in 14.3% of these studies (4/28 RCTs).ConclusionPhysical exercise has a positive impact on muscle mass and muscle function in healthy subjects aged 60 years and older. The biggest effect of exercise intervention, of any type, has been seen on physical performance (gait speed, chair rising test, balance, SPPB test, etc.). We observed huge variations in regard to the dietary supplementation protocols. Based on the included studies, mainly performed on well-nourished subjects, the interactive effect of dietary supplementation on muscle function appears limited.

Risk of falls in chronic kidney disease

“…The optimal range remains controversial 38 . Among other consequences, low levels of vitamin D in chronic kidney disease and ESRD cause high bone turnover 39 , muscle weakness, higher risk of falls 40 and high mortality risk 41,42 . The KDOQI guidelines recommend the administration of ergocalciferol and cholecalciferol to patients with CKD stage 3 to 4 if calcidiol levels are below 30 ng/ml 43 but further investigation is needed in order to identify the optimal levels of vitamin D, the appropriate regimen, dose and route of administration 35 .…”

Efficacy of Age-Specific High-Intensity Stretch-Shortening Contractions in Reversing Dynapenia, Sarcopenia, and Loss of Skeletal Muscle Quality

“…Indeed, it has been reported that, even in individuals that are otherwise considered "healthy", skeletal muscle mass has been shown to decrease~1% per year from its peak occurrence between the ages of 20-30 years old [44]. The loss of skeletal muscle mass is multi-factorial and many factors have been identified as contributors to this event; even though this is not an exhaustive list, a few of these factors are anabolic resistance [45][46][47], apoptosis [48,49], chronic inflammatory signaling associated with long-term, low-grade inflammation [50][51][52][53], and neuromuscular alterations such as motor unit loss that leads to skeletal muscle fiber denervation [45][46][47]. This latter event may be the most consequential, given that it could be thought of in terms of an explicit functional event: loss of motor units results in denervation and loss of skeletal muscle fibers, specifically the fastest skeletal muscle fibers, and finally loss of skeletal muscle function [54].…”

Sarcopenia and Exercise “The State of the Art”

“…It is a cyclical process of death and renewal. Muscle proteins undergo degradation when developing, leading to atrophy [7]. Cells are also subject to apoptosis [1].…”

“…However, there are cell renewals after the integration of amino acids. This causes the synthesis of proteins leading to muscular hypertrophy [7]. There is also stimulation of stem cells that lead to the production of satellite cells capable of repairing damaged muscles [4].…”