Prescription of resistance training for sarcopenic older adults: Does it require specific attention?

Faecal microbiota transplantation from young rats attenuates age-related sarcopenia revealed by multiomics analysis

BACKGROUND

Gut microbiota plays a key role in the development of sarcopenia via the 'gut-muscle' axis, and probiotics-based therapy might be a strategy for sarcopenia. Fecal microbiota transplantation from young donors (yFMT) has attracted much attention because of its probiotic function. However, whether or not yFMT is effective for sarcopenia in old recipients is largely unknown. Thus, we aimed to investigate the effect and mechanism of yFMT on age-related sarcopenia.

METHODS

The fecal microbiota of either young (12 weeks) or old (88 weeks) donor rats was transplanted into aged recipient rats for 8 weeks. Then, muscle mass, muscle strength, muscle function, muscle atrophy, and muscle regeneration capacity were measured. Analysis of fecal 16 s rRNA, serum non-targeted metabolomic, gut barrier integrity, and muscle transcriptome was conducted to elucidate the interaction between gut microbiota and skeletal muscles.

RESULTS

As evaluated by magnetic resonance imaging examination, grip strength test (P < 0.01), rotarod test (P < 0.05), and exhaustive running test (P < 0.05), we found that yFMT mitigated muscle mass loss, muscle strength weakness, and muscle function impairment in aged rats. yFMT also countered age-related atrophy and poor regeneration capacity in fast- and slow-switch muscles, which were manifested by the decrease in slow-switch myofibres (both P < 0.01) and muscle interstitial fibrosis (both P < 0.05) and the increase in the cross-section area of myofibres (both P < 0.001), fast-switch myofibres (both P < 0.01), and muscle satellite cells (both P < 0.001). In addition, yFMT ameliorated age-related dysbiosis of gut microbiota and metabolites by promoting the production of beneficial bacteria and metabolites-Akkermansia, Lactococcus, Lactobacillus, γ-glutamyltyrosine, 3R-hydroxy-butanoic acid, and methoxyacetic acid and inhibiting the production of deleterious bacteria and metabolites-Family_XIII_AD3011_group, Collinsella, indoxyl sulfate, indole-3-carboxilic acid-O-sulphate, and trimethylamine N-oxide. Also, yFMT prevented age-related destruction of gut barrier integrity by increasing the density of goblet cells (P < 0.0001) and the expression levels of mucin-2 (P < 0.0001) and tight junctional proteins (all P < 0.05). Meanwhile, yFMT attenuated age-related impairment of mitochondrial biogenesis and function in fast- and slow-switch muscles. Correlation analysis revealed that yFMT-induced alterations of gut microbiota and metabolites might be closely related to mitochondria-related genes and sarcopenia-related phenotypes.

CONCLUSIONS

yFMT could reshape the dysbiosis of gut microbiota and metabolites, maintain gut barrier integrity, and improve muscle mitochondrial dysfunction, eventually alleviating sarcopenia in aged rats. yFMT might be a new therapeutic strategy for age-related sarcopenia.

Engagement in Aerobic Exercise Is Associated with a Reduced Prevalence of Sarcopenia and Severe Sarcopenia in Italian Older Adults

The present study was conducted to test the association between adherence to specific exercise modalities and sarcopenia severity in Italian older adults. Data were collected as part of the ongoing Longevity Check-Up 7+ (Lookup 7+) project. Lookup 7+ began in June 2015 and has since been conducted in unconventional settings (e.g., exhibitions, malls, social events) throughout Italy. In the present study, we used data on adults 65 years and older. Sarcopenia was identified according to the simultaneous presence of dynapenia and low appendicular muscle mass. Muscle strength was measured by isometric handgrip and sit-to-stand (STS) testing. Sarcopenia was categorized as severe if participants reported difficulty or inability to walk 400 m. Engagement in running and/or swimming (RS) or strength training with or without stretching (SS) was used to define exercise modalities. Analyses were conducted in 3289 participants (mean age: 72.7 ± 5.7 years; 1814 women). The results of the binary regression showed negative associations between RS and the presence of STS-based sarcopenia in women, and between RS and STS-based severe sarcopenia in men. Collectively, these findings indicate that RS is negatively associated with the presence of sarcopenia in large sample of relatively unselected Italian older adults.

Fiber-Type Shifting in Sarcopenia of Old Age: Proteomic Profiling of the Contractile Apparatus of Skeletal Muscles

The progressive loss of skeletal muscle mass and concomitant reduction in contractile strength plays a central role in frailty syndrome. Age-related neuronal impairments are closely associated with sarcopenia in the elderly, which is characterized by severe muscular atrophy that can considerably lessen the overall quality of life at old age. Mass-spectrometry-based proteomic surveys of senescent human skeletal muscles, as well as animal models of sarcopenia, have decisively improved our understanding of the molecular and cellular consequences of muscular atrophy and associated fiber-type shifting during aging. This review outlines the mass spectrometric identification of proteome-wide changes in atrophying skeletal muscles, with a focus on contractile proteins as potential markers of changes in fiber-type distribution patterns. The observed trend of fast-to-slow transitions in individual human skeletal muscles during the aging process is most likely linked to a preferential susceptibility of fast-twitching muscle fibers to muscular atrophy. Studies with senescent animal models, including mostly aged rodent skeletal muscles, have confirmed fiber-type shifting. The proteomic analysis of fast versus slow isoforms of key contractile proteins, such as myosin heavy chains, myosin light chains, actins, troponins and tropomyosins, suggests them as suitable bioanalytical tools of fiber-type transitions during aging.

Towards multimodal boosting of motivation for fall-preventive physical activity in seniors: An iterative development evaluation study

Background

Many seniors need to increase their physical activity (PA) and participation in fall prevention exercise. Therefore, digital systems have been developed to support fall-preventive PA. Most of them lack video coaching and PA monitoring, two functionalities that may be relevant for increasing PA.

Objective

To develop a prototype of a system to support seniors' fall-preventive PA, which includes also video coaching and PA monitoring, and to evaluate its feasibility and user experience.

Methods

A system prototype was conceived by integrating applications for step-monitoring, behavioural change support, personal calendar, video-coaching and a cloud service for data management and co-ordination. Its feasibility and user experience were evaluated in three consecutive test periods combined with technical development. In total, 11 seniors tested the system at home for four weeks with video coaching from health care professionals.

Results

Initially, the system's feasibility was non-satisfactory due to insufficient stability and usability. However, most problems could be addressed and amended. In the third (last) test period, both seniors and coaches experienced the system prototype to be fun, flexible and awareness-raising. Interestingly, the video coaching which made the system unique compared to similar systems was highly appreciated. Nonetheless, even the users in the last test period highlighted issues due to insufficient usability, stability and flexibility. Further improvements in these areas are needed.

Conclusions

Video coaching in fall-preventive PA can be valuable for both seniors and health care professionals. High reliability, usability and flexibility of systems supporting seniors are essential.

Effectiveness of a Multicomponent Training Program on Physical Performance and Muscle Quality in Older Adults: A Quasi-Experimental Study

Aging is associated with a decrease in functional capacity, manifested by a loss of strength, physical performance and muscle quality. Multicomponent training (MCT), characterized by the combination of at least three types of training, could be a good strategy to counteract these changes. To date there are no studies evaluating the effectiveness of MCT in improving both physical performance and muscle quality simultaneously. The aim of this study is to evaluate the changes produced by an MCT program on both physical performance and muscle quality in a population of healthy older adults. Sixteen healthy older adults were recruited to perform a 15-session multicomponent training intervention. Physical performance was assessed by different functional tests, and muscle quality was assessed by tensiomyography and myotonometry. The main results of this study show some improvement in functional tests, but not in muscle quality parameters, except for vastus lateralis stiffness. MCT is able to generate improvements in the physical performance of older adults, but these improvements are not reflected in muscle quality parameters measured by tensiomyography and myotonometry.