Effects of elastic band resistance training and nutritional supplementation on muscle quality and circulating muscle growth and degradation factors of institutionalized elderly women: the Vienna Active Ageing Study (VAAS)

[Development and Effects of Combined Exercise Program for Older Adults with Sarcopenia Based on Transtheoretical Model]

PURPOSE

The purpose of this study was to develop and examine the effects of combined exercise program for older adults with sarcopenia based on transtheoretical model (TTM).

METHODS

A non-equivalent control group with a pretest-posttest design was used. The subjects consisted of 43 older adults with sarcopenia in precontemplation stage, contemplation stage and preparation stage of TTM (experimental group: 22, control group: 21). The developed program consisted of 36 sessions for 12 weeks including combined exercise (60 minutes) and TTM based strategies for enhancing exercise behavior (10 minutes) per session. Data were collected before, immediately after the program between July 31 to October 27, 2017. The data were analyzed using independent t-test, Mann-Whitney U test with SPSS/WIN 18.0.

RESULTS

Compared with their counterparts in the control groups, older adults with sarcopenia in the experimental group showed a significantly greater improvement in process of exercise behavior change, pros and cons of decisional balance for exercise behavior, exercise self-efficacy, parameters of muscle, and the level of physical performance.

CONCLUSION

The study findings indicate that this combined exercise program for older adults with sarcopenia based on TTM model was effective and can be recommended as a nursing intervention for older adults with sarcopenia.

In Vivo Flattening of the Central Aponeurosis of the Rectus Femoris Due to Knee Extension Torque in Healthy Young and Elderly Individuals With Knee Osteoarthritis

ABSTRACT

We aimed to elucidate the relationship between active force production and the curvature of the central aponeurosis (CA) of the rectus femoris in young healthy participants as fundamental data and compare the muscle CA curvature before and after straight leg raising (SLR) training in participants with knee osteoarthritis (OA). Central aponeurosis curvature was determined during submaximal and maximal voluntary contractions (MVCs) using ultrasonography. Twenty-five young healthy female volunteers underwent ultrasonographic measurements under conditions of isometric MVC. They were divided into a flat shaped CA group (flat) and an incompletely flat shaped CA group (remnant). Central aponeurosis curvature was calculated as the ratio of CA height and length in the axial view. Central aponeurosis shape and muscular strength before and after muscle training were measured in 11 participants with knee OA. In the young healthy individuals, maximal voluntary torque and changes in CA curvature were significantly higher in the flat group than in the remnant group (2.15 Nm/kg and - 17.7% vs 1.75 Nm/kg and -9.8%, respectively; P = 0.005). The rate of change of the CA curvature during contraction was significantly correlated with maximal voluntary torque corrected for body mass (r = 0.512). The CA curvature progressively decreased as %MVC increased. In the OA group, CA curvature during MVC after SLR training was significantly lower than that before SLR training (3.2% vs 7.2%; P = 0.031). Central aponeurosis curvature was associated with muscle strength, and the results supported our hypothesis that geometric observation of CA changes during contractions may reflect muscle fiber function. We aim to develop a new ultrasonographic skeletal muscle evaluation method based on our present findings.

Effect of a Resistance Training Program on Sarcopenia and Functionality of the Older Adults Living in a Nursing Home

IMPORTANCE

There are currently few evidence about resistance training as a treatment for sarcopenia in the nursing home setting.

OBJECTIVE

To evaluate the effect of a resistance training program on the sarcopenia and functionality of the elderly living in a nursing home.

DESIGN, SETTING, AND PARTICIPANTS

A blinded longitudinal intervention study conducted in elderly people living in a nursing home from August to November 2016. Participants included a convenience sample of 19 older adults.

INTERVENTION

We prescribed a resistance exercise program three times a week for 12 weeks. The scheme was two to three sets with eight to 15 repetitions per exercise.

MAIN OUTCOME AND MEASURES

The primary outcome was an increase in muscle strength and an improvement in physical performance of the elderly people living in nursing homes.

RESULTS

19 older adults between 77.7 ± 8.9 years old, completed the 12 week resistance exercise program achieving a significant increase in muscle strength to 5.7 Kg (p = 0.0001) as well as nutritional intake for the first four weeks (p = 0.001); we found an improvement in physical performance (p = 0.0001) in balance (p = 0.0001), chair stand (p = 0.036) and gait speed (p = 0.0001). Of the 47.4% that reached sarcopenia degree, in the end it was 33.3%. A relationship with nutritional status (p = 0.004) and age (p = 0.019) was found with the initial and final handgrip strength (p = 0.041).

CONCLUSIONS AND RELEVANCE

The resistance training program improves the functionality (muscle strength and physical performance), with the benefit of the decrease in severe sarcopenia.

Effects of Protein Supplementation Combined with Exercise Intervention on Frailty Indices, Body Composition, and Physical Function in Frail Older Adults

Aging poses a high risk of lean mass loss, which can be effectively improved through resistance exercise training (RET), or multicomponent exercise training (MET) as well as nutrition supplementation, such as protein supplementation (PS). This study investigated the effects of PS plus exercise training on frail older individuals. A comprehensive search of online databases was performed to identify randomized controlled trials (RCTs) that reported the efficacy of PS combined with RET or MET in frail older individuals. The included RCTs were analyzed through a meta-analysis and risk-of-bias assessment. We finally included 22 RCTs in the meta-analysis, with a mean (range/total) Physiotherapy Evidence Database score of 6.7 (4⁻9/10). PS plus exercise training significantly improved the frailty status (odds ratio = 2.77; p = 0.006), lean mass (standard mean difference (SMD) = 0.52; p < 0.00001), leg strength (SMD = 0.37; p < 0.00001), and walking speed (SMD = 0.32; p = 0.002). Subgroup analyses revealed that PS plus MET exert significant effects on frailty indices, whereas PS plus RET further improves lean mass. Our findings suggest that PS plus RET as well as MET is effective in improving frailty status, lean mass, muscle strength, and physical mobility in frail older individuals.

Serum Myostatin Levels Are Higher in Fitter, More Active, and Non-Frail Long-Term Nursing Home Residents and Increase after a Physical Exercise Intervention

BACKGROUND

Myostatin has been proposed as a candidate biomarker for frailty and sarcopenia. However, the relationship of myostatin with these conditions remains inconclusive.

OBJECTIVE

To determine the association of serum myostatin concentration with body composition, physical fitness, physical activity level, and frailty in long-term nursing home residents. We also aimed to ascertain the effect of an exercise program on myostatin levels.

METHODS

We obtained study data on 112 participants from long-term nursing homes. Participants were randomly assigned to a control or an intervention group and performed a 6-month multicomponent exercise program. Serum myostatin levels were analyzed by ELISA. Assessments also included body composition (anthropometry and bioelectrical impedance), physical fitness (Senior Fitness Test), physical activity level (accelerometry), and frailty (Fried frailty criteria, Clinical Frailty Scale, and Tilburg frailty indicator).

RESULTS

The concentration of myostatin at baseline was positively correlated with: a leaner body composition (p < 0.05), and a higher number of steps per day and light and moderate-vigorous physical activity in women (p < 0.005); greater upper and lower limb strength, endurance, and poorer flexibility (p < 0.05) in men; and better performance (less time) in the 8-ft timed up-and-go test in both women (p < 0.01) and men (p < 0.005). We observed higher concentrations of serum myostatin in non-frail than in frail participants (p < 0.05). Additionally, we found that the implemented physical exercise intervention, which was effective to improve physical fitness, increased myostatin concentration in men (p < 0.05) but not in women. The improvements in physical condition were related with increases in serum myostatin only in men (p < 0.05-0.01).

CONCLUSIONS

Higher serum levels of myostatin were found to be associated with better physical fitness. The improvements in physical fitness after the intervention were positively related to increases in myostatin concentrations in men. These results seem to rule out the idea that high serum myostatin levels are indicative of frailty in long-term nursing home residents. However, although the direction of association was opposite to that expected for the function of myostatin, the use of this protein as a biomarker for physical fitness, rather than frailty, merits further study.

Relationship of muscle function to circulating myostatin, follistatin and GDF11 in older women and men

Background

Myostatin, its inhibitor follistatin, and growth/differentiation factor 11 (GDF11) have been proposed as factors that could potentially modify biological aging. The study aimed to test whether there is a relationship between these plasma circulating proteins and muscle strength, power and optimal shortening velocity (υ_opt) of older adults.

Methods

The cross-sectional study included 56 women and 45 men aged 60 years and older. Every participant underwent examination which included anthropometric and bioimpedance analysis measurements, functional and cognitive performance tests, muscle strength of upper and lower extremities, muscle power testing with two different methods and blood analyses.

Results

Women had higher plasma levels of myostatin and GDF11 than men. Men had higher plasma level of follistatin than women. In women, plasma level of myostatin was negatively correlated with left handgrip strength and υ_opt. Follistatin was negatively correlated with maximum power output (P_max), power relative to kg of body mass (P_max∙kg^− 1) (friction-loaded cycle ergometer) and power at 70% of the 1-repetition maximum (1RM) strength value (P70%) of leg press (Keiser pneumatic resistance training equipment), and positively correlated with the Timed Up & Go (TUG) test. GDF11 was negatively correlated with body mass, body mass index, waist circumference, fat mass and the percentage of body fat. In men, there were no significant correlations observed between circulating plasma proteins and muscle function measures.

Conclusions

The circulating plasma myostatin and follistatin are negatively associated with muscle function in older women. There is stronger relationship between these proteins and muscle power than muscle strength. GDF11 has a higher association with the body mass and composition than muscle function in older women.

Age and the effect of exercise, nutrition and cognitive training on oxidative stress - The Vienna Active Aging Study (VAAS), a randomized controlled trial

The purpose of this study was to investigated the effect of age - over or under life-expectancy (LE) - on six months resistance training alone or combined with a nutritional supplement, and cognitive training by analyzing markers for oxidative stress and antioxidant defense in institutionalized elderly, living in Vienna. Three groups (n = 117, age = 83.1 ± 6.1 years) - resistance training (RT), RT combined with protein and vitamin supplementation (RTS) or cognitive training (CT) - performed two guided training sessions per week for six months. Oxidative stress, antioxidant defense and DNA strand breaks were analyzed and transformed into an "antioxidant factor" to compare the total effect of the intervention. Physical fitness was assessed by the 6-min-walking, the chair-rise and the handgrip strength tests. We observed significant negative baseline correlations between 8-oxo-7.8-dihydroguanosine and handgrip strength (r = -0.350, p = 0.001), and between high sensitive troponin-T and the 6-min-walking test (r = -0.210, p = 0.035). RT and RTS groups, showed significant improvements in physical performance. Over LE, subjects of the RT group demonstrated a significant greater response in the "antioxidant factor" compared to RTS and CT (RT vs. RTS p = 0.033, RT vs. CT p = 0.028), whereas no difference was observed between the intervention groups under LE. Six months of elastic band resistance training lead to improvements in antioxidant defense, DNA stability and oxidative damage, summarized in the "antioxidant factor", however mainly in subjects over their statistical LE. Consuming a supplement containing antioxidants might inhibit optimal cellular response to exercise. The study was approved by the ethics committee of the City of Vienna (EK-11-151-0811) and registered at ClinicalTrials.gov, NCT01775111.

Protein Intake and Distribution in Relation to Physical Functioning and Quality of Life in Community-Dwelling Elderly People: Acknowledging the Role of Physical Activity

Increasing total protein intake and a spread protein intake distribution are potential strategies to attenuate sarcopenia related loss of physical function and quality of life. The aim of this cross-sectional study was to investigate whether protein intake and protein intake distribution are associated with muscle strength, physical function and quality of life in community-dwelling elderly people with a wide range of physical activity. Dietary and physical activity data were obtained from two studies (N = 140, age 81 ± 6, 64% male), with the following outcome measures: physical functioning (Short Physical Performance Battery (SPPB), comprising balance, gait speed and chair rise tests), handgrip strength and quality of life (EQ-5D-5L). Protein intake distribution was calculated for each participant as a coefficient of variance (CV = SD of grams of protein intake per main meal divided by the average total amount of proteins (grams) of the main meals). Based on the CV, participants were divided into tertiles and classified as spread, intermediate or pulse. The average total protein intake was 1.08 ± 0.29 g/kg/day. Total protein intake was not associated with outcome measures using multivariate regression analyses. Individuals with a spread protein diet during the main meals (CV < 0.43) had higher gait speed compared to those with an intermediate diet (CV 0.43⁻0.62) (β = -0.42, p = 0.035), whereas a spread and pulse protein diet were not associated with SPPB total score, chair rise, grip strength and Quality-Adjusted Life Year (QALY). The interaction of higher physical activity and higher total protein intake was significantly associated with higher quality of life (β = 0.71, p = 0.049). While this interaction was not associated with SPPB or grip strength, the association with quality of life emphasizes the need for a higher total protein intake together with an active lifestyle in the elderly.

Strength training increases skeletal muscle quality but not muscle mass in old institutionalized adults: a randomized, multi-arm parallel and controlled intervention study

BACKGROUND

Age related loss of skeletal muscle mass is accompanied by changes in muscle quality leading to impairment of functional status.

AIM

This study investigated the effect of resistance training and nutritional supply on muscle mass and muscle quality in very old institutionalized adults.

DESIGN

Prospective, randomized, multi-arm parallel and controlled intervention study.

SETTING

This study was conducted in five retirement care facilities.

POPULATION

This subgroup of the Vienna Active Ageing Study included 54 women and men (82.4±6.0 years) with impaired health status. Participants were randomly assigned either to elastic band resistance training (N.=16), training with nutritional supplementation (N.=21) or control group (N.=17).

METHODS

Health status was assessed at baseline with functional tests, cognitive status, nutritional status, sum of medications as well as sum of diseases. Skeletal muscle mass, determined by dual-energy X-ray absorptiometry, isokinetic knee extension and flexion force and handgrip strength were assessed at baseline and after 6 months. Muscle quality of lower extremities was defined as ratio of the extensor (MQ_LE (Ext.)) or flexor strength (MQ_LE (Flex.)) to lean leg mass. Muscle quality of upper extremity was defined as ratio of handgrip strength to lean arm mass. Follow-up examinations were performed after 12 and 18 months of intervention.

RESULTS

Muscle quality, but not muscle mass, showed significant correlations to functional tests at baseline (0.300 - 0.614, P<0.05). Resistance training significantly enhanced muscle quality of lower extremity after 6 months (MQ_LE (Ext.) +19.8%, MQ_LE (Flex.) +30.8%, P<0.05). Nutritional supplementation could not further increase the training effect. Participants with lower muscle quality at baseline benefit most from the training intervention. Skeletal muscle mass was not changed by any intervention.

CONCLUSIONS

Resistance training with elastic bands improved muscle quality in very old people. Additional nutritional supplementation was not able to further improve the effects obtained by training alone.

CLINICAL REHABILITATION IMPACT

Elastic band resistance training could be safely used to improve muscle quality even in old people with impaired health status. Weak and chronically ill participants benefit most from this training.

Effects of protein supplementation combined with resistance exercise on body composition and physical function in older adults: a systematic review and meta-analysis

Background: Overweight and obese older people face a high risk of muscle loss and impaired physical function, which may contribute to sarcopenic obesity. Resistance exercise training (RET) has a beneficial effect on muscle protein synthesis and can be augmented by protein supplementation (PS). However, whether body weight affects the augmentation of muscular and functional performance in response to PS in older people undergoing RET remains unclear.Objective: This study was conducted to identify the effects of PS on the body composition and physical function of older people undergoing RET.Design: We performed a comprehensive search of online databases to identify randomized controlled trials (RCTs) reporting the efficacy of PS for lean mass gain, strength gain, and physical mobility improvements in older people undergoing RET.Results: We included 17 RCTs; the overall mean ± SD age and body mass index (BMI; in kg/m²) in these RCTs were 73.4 ± 8.1 y and 29.7 ± 5.5, respectively. The participants had substantially greater lean mass and leg strength gains when PS and RET were used than with RET alone, with the standard mean differences (SMDs) being 0.58 (95% CI: 0.32, 0.84) and 0.69 (95% CI: 0.39, 0.98), respectively. The subgroup of studies with a mean BMI ≥30 exhibited substantially greater lean mass (SMD: 0.53; 95% CI: 0.19, 0.87) and leg strength (SMD: 0.88; 95% CI: 0.42, 1.34) gains in response to PS. The subgroup of studies with a mean BMI <30 also exhibited relevant gains in response to PS.Conclusions: Compared with RET alone, PS combined with RET may have a stronger effect in preventing aging-related muscle mass attenuation and leg strength loss in older people, which was found in studies with a mean BMI ≥30 and in studies with a mean BMI <30. Clinicians could use nutrition supplement and exercise strategies, especially PS plus RET, to effectively improve the physical activity and health status of all older patients.

Effects of elastic resistance exercise on body composition and physical capacity in older women with sarcopenic obesity: A CONSORT-compliant prospective randomized controlled trial

BACKGROUND

Sarcopenia is associated with loss of muscle mass and an increased risk of physical disability in elderly people. However, the prevalence of sarcopenia has increased in obese elderly populations. The purpose of this study was to identify the clinical efficacy of elastic resistance exercise training (RET) in patients with sarcopenic obesity.

METHODS

This study was conducted at the rehabilitation center of a university-based teaching hospital and was designed as a prospective and randomized controlled trial with an intention-to-treat analysis. A total of 46 women aged 67.3 (5.2) years were randomly assigned to an experimental group (EG) and control group (CG). The EG underwent elastic RET for 12 weeks, and the CG received no RET intervention. All outcome measures were assessed at the baseline and posttest, including body composition measured using dual-energy X-ray absorptiometry, muscle quality (MQ) defined as a ratio of muscular strength to muscle mass, and physical capacity assessed using functional mobility tests. One-way analysis of covariance and Pearson correlation were used to compare outcomes between the 2 groups and to identify the relationship between changes in body composition and physical outcomes, respectively. A chi-square test was performed to identify differences in qualitative data between the 2 groups.

RESULTS

At the posttest, a significant between-group difference was observed in fat-free mass, MQ, and physical capacity (all P < .05); and a significant correlation was found between leg-lean-mass change and gait speed (r = 0.36; P < .05). After 12 weeks of elastic RET intervention, the EG had significantly fewer patients exhibiting sarcopenia (P < .05) and experiencing physical difficulty (P < .001) than the CG.

CONCLUSION

The present data suggest that elastic resistance exercise exerted benefits on the body composition, MQ, and physical function in patients with sarcopenic obesity. Regular exercise incorporating elastic RET should be used to attenuate muscle mass loss and prevent physical difficulty in obese older adults with sarcopenia on reconditioning therapy.

TRIAL REGISTRATION

Chinese Clinical Trial Registry, ChiCTR-IPR-15006069.

Inflammatory markers, sarcopenia and its diagnostic criteria among the elderly: a systematic review

Abstract Objective: To identify the relationship between inflammatory markers and sarcopenia, and the diagnostic criteria of the condition among the elderly. Methods: A systematic review was performed based on the consultation of the PubMed and LILACS databases. Eligible original articles were those involving individuals aged 60 years or more, which investigated sarcopenia [low muscle mass (MM) associated with poor muscle strength and/or reduced physical performance, according to the European Working Group on Sarcopenia in Older People consensus (EWGSOP)] or its diagnostic criteria, published in English or Portuguese, between 2010-2015. Results: Four articles were included in the review, the principle results of which were: the growth differentiation factor (GDF-15) exhibited a negative correlation with MM, handgrip strength and gait speed; the insulin-like growth factor-1 (IGF-1) correlated positively with MM; follistatin exhibited a weak correlation with physical performance; activin A and myostatin did not correlate with the diagnostic criteria; the highest tercile of extracellular heat shock protein 72 (eHsp72) was associated with lower median levels of MM, handgrip strength and gait speed; elderly persons with low MM had higher serum ferritin concentrations; women with low MM exhibited lower serum concentration levels of C-reactive protein (CRP). Conclusion: the six investigated inflammatory markers (GDF-15, IGF-1, follistatin, eHsp72, ferritin and CRP) were associated with the diagnostic criteria for sarcopenia, but not with sarcopenia itself. As research in this area is still developing, additional studies are required to broaden knowledge and eventually establish the role of these markers in the diagnosis and management of sarcopenia.

High-intensity interval training (HIIT) increases insulin-like growth factor-I (IGF-I) in sedentary aging men but not masters' athletes: an observational study

INTRODUCTION

The aim of this investigation was to examine the impact high-intensity interval training (HIIT) on serum insulin-like growth factor-I (IGF-I) in active compared with sedentary aging men.

METHODS

22 lifetime sedentary (SED; 62 ± 2 years) and 17 masters' athletes (LEX; 60 ± 5 years) were recruited to the study. As HIIT requires preconditioning exercise in sedentary cohorts, the study required three assessment phases; enrollment (phase A), following preconditioning exercise (phase B), and post-HIIT (phase C). Serum IGF-I was determined by electrochemiluminescent immunoassay.

RESULTS

IGF-I was higher in LEX compared to SED at baseline (p = 0.007, Cohen's d = 0.91), and phase B (p = 0.083, Cohen's d = 0.59), with only a small difference at C (p = 0.291, Cohen's d = 0.35). SED experienced a small increase in IGF-I following preconditioning from 13.1 ± 4.7 to 14.2 ± 6.0 μg·dl^-1 (p = 0.376, Cohen's d = 0.22), followed by a larger increase post-HIIT (16.9 ± 4.4 μg·dl^-1), which was significantly elevated compared with baseline (p = 0.002, Cohen's d = 0.85), and post-preconditioning (p = 0.005, Cohen's d = 0.51). LEX experienced a trivial changes in IGF-I from A to B (18.2 ± 6.4 to 17.2 ± 3.7 μg·dl^-1 [p = 0.538, Cohen's d = 0.19]), and a small change post-HIIT (18.4 ± 4.1 μg·dl^-1 [p = 0.283, Cohen's d = 0.31]). Small increases were observed in fat-free mass in both groups following HIIT (p < 0.05, Cohen's d = 0.32-0.45).

CONCLUSIONS

In conclusion, HIIT with preconditioning exercise abrogates the age associated difference in IGF-I between SED and LEX, and induces small improvements in fat-free mass in both SED and LEX.

The effect of obesity on the contractile performance of isolated mouse soleus, EDL, and diaphragm muscles

Obesity affects the major metabolic and cellular processes involved in skeletal muscle contractility. Surprisingly, the effect of obesity on isolated skeletal muscle performance remains unresolved. The present study is the first to examine the muscle-specific changes in contractility following dietary-induced obesity using an isolated muscle work-loop (WL) model that more closely represents in vivo muscle performance. Following 16-wk high-calorific feeding, soleus (SOL), extensor digitorum longus (EDL), and diaphragm (DIA) were isolated from female (CD-1) mice, and contractile performance was compared against a lean control group. Obese SOL produced greater isometric force; however, isometric stress (force per unit muscle area), absolute WL power, and normalized WL power (watts per kilogram muscle mass) were unaffected. Maximal isometric force and absolute WL power of the EDL were similar between groups. For both EDL and DIA, isometric stress and normalized WL power were reduced in the obese groups. Obesity caused a significant reduction in fatigue resistance in all cases. Our findings demonstrate a muscle-specific reduction in contractile performance and muscle quality that is likely related to in vivo mechanical role, fiber type, and metabolic profile, which may in part be related to changes in myosin heavy chain expression and AMP-activated protein kinase activity. These results infer that, beyond the additional requirement of moving a larger body mass, functional performance and quality of life may be further limited by poor muscle function in obese individuals. As such, a reduction in muscle performance may be a substantial contributor to the negative cycle of obesity.

NEW & NOTEWORTHY

The effect of obesity on isolated muscle function is surprisingly underresearched. The present study is the first to examine the effects of obesity on isolated muscle performance using a method that more closely represents real-world muscle function. This work uniquely establishes a muscle-specific profile of mechanical changes in relation to underpinning mechanisms. These findings may be important to understanding the negative cycle of obesity and in designing interventions for improving weight status.

Elastic band resistance training influences transforming growth factor-ß receptor I mRNA expression in peripheral mononuclear cells of institutionalised older adults: the Vienna Active Ageing Study (VAAS)

Background

Ageing, inactivity and obesity are associated with chronic low-grade inflammation contributing to a variety of lifestyle-related diseases. Transforming growth factor-β (TGF-β) is a multimodal protein with various cellular functions ranging from tissue remodelling to the regulation of inflammation and immune functions. While it is generally accepted that aerobic exercise exerts beneficial effects on several aspects of immune functions, even in older adults, the effect of resistance training remains unclear. The aim of this study was to investigate whether progressive resistance training (6 months) with or without nutritional supplementation (protein and vitamins) would influence circulating C-reactive protein and TGF-β levels as well as TGF-β signalling in peripheral mononuclear cells (PBMCs) of institutionalised adults with a median age of 84.5 (65.0–97.4) years.

Results

Elastic band resistance training significantly improved performance as shown by the arm-lifting test (p = 0.007), chair stand test (p = 0.001) and 6-min walking test (p = 0.026). These results were paralleled by a reduction in TGF-β receptor I (TGF-βRI) mRNA expression in PBMCs (p = 0.006), while circulating inflammatory markers were unaffected. Protein and vitamin supplementation did not provoke any additional effects. Interestingly, muscular endurance of upper and lower body and aerobic performance at baseline were negatively associated with changes in circulating TGF-β at the early phase of the study. Furthermore, drop-outs of the study were characterised not only by lower physical performance but also higher TGF-β and TGF-βRI mRNA expression, and lower miRNA-21 expression.

Conclusions

Progressive resistance training with elastic bands did not influence chronic low-grade inflammation but potentially affected TGF-β signalling in PBMCs through altered TGF-βRI mRNA expression. There appears to be an association between physical performance and TGF-β expression in PBMCs of older adults, in which the exact mechanisms need to be clarified.