Possibility of leg muscle hypertrophy by ambulation in older adults: a brief review

Effects of therapeutic exercise on the motor function of adults with Down syndrome: a systematic review and meta-analysis

Therapeutic exercise exerts positive effects by mitigating or reducing the motor or cognitive changes that people with Down syndrome undergo throughout their life. There are no updated systematic reviews that integrate the evidence available in a way that facilitates decision-making for physical rehabilitation teams. This study therefore aimed to consolidate the information available and compare the effects of different types of physical exercise on the motor function of adults with DS. We conducted a systematic review and meta-analysis of randomized clinical trials and quasi-experimental studies. The literature search was performed between January 2023 and February 2023 using the PubMed, SCIELO, Epistemonikos, and Lilacs databases. Studies were selected according to pre-determined inclusion and exclusion criteria. The risk-of-bias assessment was performed using the risk-of-bias rating tool for randomized clinical trial (RoB) and the risk of bias of non-randomized comparative studies was assessed using the risk of bias in non-randomized studies of interventions (ROBINS-I) tool. Risk-of-bias assessment and meta-analyses were performed using the RevMan software package. Sixteen studies met the eligibility criteria for the qualitative synthesis and 4 were included in the meta-analyses. Combined exercise significantly increased muscle strength both in the upper limbs (SMD = 0.74 [95% CI 0.25-1.22]) and lower limbs (SMD = 0.56[95% CI 0.08-1.04]). Aerobic exercise improved spatiotemporal gait parameters. Aerobic exercise showed significant improvements in dynamic balance while combined exercise significantly increased dynamic and static balance. The certainty of the evidence was low to moderate for all outcomes. There was low and moderate certainty of evidence for the outcomes proposed in this review. However, therapeutic exercise could be effective in improving muscle strength and gait functionality.

Comparing the Effects of Two Perturbation-Based Balance Training Paradigms in Fall-Prone Older Adults: A Randomized Controlled Trial

INTRODUCTION

There is increasing evidence that perturbation-based balance training (PBT) is highly effective in preventing falls at older age. Different PBT paradigms have been presented so far, yet a systematic comparison of PBT approaches with respect to feasibility and effectiveness is missing. Two different paradigms of PBT seem to be promising for clinical implementation: (1) technology-supported training on a perturbation treadmill (PBTtreadmill); (2) training of dynamic stability mechanisms in the presence of perturbations induced by unstable surfaces (PBTstability). This study aimed to compare both program's feasibility and effectiveness in fall-prone older adults.

METHODS

In this three-armed randomized controlled trial, seventy-one older adults (74.9 ± 6.0 years) with a verified fall risk were randomly assigned into three groups: PBTtreadmill on a motorized treadmill, PBTstability using unstable conditions such as balance pads, and a passive control group (CG). In both intervention groups, participants conducted a 6-week intervention with 3 sessions per week. Effects were assessed in fall risk (Brief-BEST), balance ability (Stepping Threshold Test, center of pressure, limits of stability), leg strength capacity, functional performance (Timed Up and Go Test, Chair-Stand), gait (preferred walking speed), and fear of falling (Short FES-I).

RESULTS

Fifty-one participants completed the study. Training adherence was 91% for PBTtreadmill and 87% for PBTstability, while no severe adverse events occurred. An analysis of covariance with an intention-to-treat approach revealed statistically significant group effects in favor of PBTstability in the Brief-BEST (p = 0.009, η2 = 0.131) and the limits of stability (p = 0.020, η2 = 0.110) and in favor of PBTtreadmill in the Stepping Threshold Test (p < 0.001, η2 = 0.395). The other outcomes demonstrated no significant group effects.

CONCLUSION

Both training paradigms demonstrated high feasibility and were effective in improving specific motor performances in the fall-prone population and these effects were task specific. PBTtreadmill showed higher improvements in reactive balance, which might have been promoted by the unpredictable nature of the included perturbations and the similarity to the tested surface perturbation paradigm. PBTstability showed more wide-ranging effects on balance ability. Consequently, both paradigms improved fall risk-associated measures. The advantages of both formats should be evaluated in light of individual needs and preferences. Larger studies are needed to investigate the effects of these paradigms on real-life fall rates.

Efficacy of low-load blood flow restricted resistance EXercise in patients with Knee osteoarthritis scheduled for total knee replacement (EXKnee): protocol for a multicentre randomised controlled trial

INTRODUCTION

Up to 20% of patients undergoing total knee replacement (TKR) surgery report no or suboptimal pain relief after TKR. Moreover, despite chances of recovering to preoperative functional levels, patients receiving TKR have demonstrated persistent deficits in quadriceps strength and functional performance compared with healthy age-matched adults. We intend to examine if low-load blood flow restricted exercise (BFRE) is an effective preoperative method to increase functional capacity, lower limb muscle strength and self-reported outcomes after TKR. In addition, the study aims to investigate to which extent preoperative BFRE will protect against surgery-related atrophy 3 months after TKR.

METHODS

In this multicentre, randomised controlled and assessor blinded trial, 84 patients scheduled for TKR will be randomised to receive usual care and 8 weeks of preoperative BFRE or to follow usual care-only. Data will be collected before randomisation, 3-4 days prior to TKR, 6 weeks, 3 months and 12 months after TKR. Primary outcome will be the change in 30 s chair stand test from baseline to 3-month follow-up. Key secondary outcomes will be timed up and go, 40 me fast-paced walk test, isometric knee extensor and flexor strength, patient-reported outcome and selected myofiber properties.Intention-to-treat principle and per-protocol analyses will be conducted. A one-way analysis of variance model will be used to analyse between group mean changes. Preintervention-to-postintervention comparisons will be analysed using a mixed linear model. Also, paired Student's t-test will be performed to gain insight into the potential pretraining-to-post-training differences within the respective training or control groups and regression analysis will be used for analysation of associations between selected outcomes.

ETHICAL APPROVAL

The trial has been accepted by the Central Denmark Region Committee on Biomedical Research Ethics (Journal No 10-72-19-19) and the Danish Data Protection Agency (Journal No 652164). All results will be published in international peer-reviewed scientific journals regardless of positive, negative or inconclusive results.

TRIAL REGISTRATION NUMBER

NCT04081493.

Menthol-induced cutaneous stimulation combined with self-paced walking training improves knee extension performance in untrained older healthy females

[Purpose] The present study aimed to investigate whether self-paced walking training utilizing the facilitating effect of skin cooling with menthol gel application was effective in untrained older healthy females. [Participants and Methods] Forty-two untrained healthy older females (aged 60-69 years) were divided into the following three groups: (i) Walking training with menthol group: G_M, (ii) Walking training group: G_W, and (iii) Control group: G_C. The participants in G_M and G_W performed self-paced walking for 30 minutes a day, 2 times a week, for 6 weeks. Menthol gel was applied to the front of the thigh of the participants in G_M. Maximal voluntary contraction and rate of force development were measured pre- and post-training and walking speed was measured during the training. The number of steps taken and walking speed in daily activity were measured and the average of these parameters per day were calculated. [Results] The main findings were [1] knee extension muscle strength increased in G_M and G_W, and [2] rate of force development only improved in G_M. [Conclusion] These results suggest that walking training utilizing the facilitating effect of skin cooling enhances muscle function in untrained older healthy females and that the present skin cooling method with menthol gel application may be recommended as a training strategy.

RaceRunning training improves stamina and promotes skeletal muscle hypertrophy in young individuals with cerebral palsy

Background

Individuals with cerebral palsy (CP) are less physically active, spend more time sedentary and have lower cardiorespiratory endurance as compared to typically developed individuals. RaceRunning enables high-intensity exercise in individuals with CP with limited or no walking ability, using a three-wheeled running bike with a saddle and a chest plate for support, but no pedals. Training adaptations using this type of exercise are unknown.

Methods

Fifteen adolescents/young adults (mean age 16, range 9–29, 7 females/8 males) with CP completed 12 weeks, two sessions/week, of RaceRunning training. Measurements of cardiorespiratory endurance (6-min RaceRunning test (6-MRT), average and maximum heart rate, rate of perceived exertion using the Borg scale (Borg-RPE)), skeletal muscle thickness (ultrasound) of the thigh (vastus lateralis and intermedius muscles) and lower leg (medial gastrocnemius muscle) and passive range of motion (pROM) of hip, knee and ankle were collected before and after the training period.

Results

Cardiorespiratory endurance increased on average 34% (6-MRT distance; pre 576 ± 320 m vs. post 723 ± 368 m, p < 0.001). Average and maximum heart rate and Borg-RPE during the 6-MRT did not differ pre vs. post training. Thickness of the medial gastrocnemius muscle increased 9% in response to training (p < 0.05) on the more-affected side. Passive hip flexion increased (p < 0.05) on the less-affected side and ankle dorsiflexion decreased (p < 0.05) on the more affected side after 12 weeks of RaceRunning training.

Conclusions

These results support the efficacy of RaceRunning as a powerful and effective training modality in individuals with CP, promoting both cardiorespiratory and peripheral adaptations.

Hemodynamic and perceptual responses to blood flow-restricted exercise among patients undergoing dialysis

End-stage kidney disease is associated with reduced exercise capacity, muscle atrophy, and impaired muscle function. While these may be improved with exercise, single modalities of exercise do not traditionally elicit improvements across all required physiological domains. Blood flow-restricted exercise may improve all of these physiological domains with low intensities traditionally considered insufficient for these adaptions. Investigation of this technique appeals, but is yet to be evaluated, in patients undergoing dialysis. With the use of a progressive crossover design, 10 satellite patients undergoing hemodialysis underwent three exercise conditions over 2 wk: two bouts (10 min) of unrestricted cycling during two consecutive hemodialysis sessions (condition 1), two bouts of cycling with blood flow restriction while off hemodialysis on 2 separate days (condition 2), and two bouts of cycling with blood flow restriction during two hemodialysis sessions (condition 3). Outcomes included hemodynamic responses (heart rate and blood pressure) throughout all sessions, participant-perceived exertion and discomfort on a Borg scale, and evaluation of ultrafiltration rates and dialysis adequacy (Kt/V) obtained post hoc. Hemodynamic responses were consistent regardless of condition. Significant increases in heart rate, systolic blood pressure, and mean arterial blood pressure (P < 0.05) were observed postexercise followed by a reduction in blood pressures during the 60-min recovery (12, 5, and 11 mmHg for systolic, diastolic, and mean arterial pressures, respectively). Blood pressures returned to predialysis ranges following the recovery period. Blood flow restriction did not affect ultrafiltration achieved or Kt/V. Hemodynamic safety and tolerability of blood flow restriction during aerobic exercise on hemodialysis is comparable to standard aerobic exercise.

A Randomized Clinical Trial Comparing Three Different Exercise Strategies for Optimizing Aerobic Capacity and Skeletal Muscle Performance in Older Adults: Protocol for the DART Study

Background: Age-related declines in physical function lead to decreased independence and higher healthcare costs. Individuals who meet the endurance and resistance exercise recommendations can improve their physical function and overall fitness, even into their ninth decade. However, most older adults do not exercise regularly, and the majority of those who do only perform one type of exercise, and in doing so are not getting the benefits of endurance or resistance exercise. Herein we present the study protocol for a randomized clinical trial that will investigate the potential for high-intensity interval training (HIIT) to improve maximal oxygen consumption, muscular power, and muscle volume (primary outcomes), as well as body composition, 6-min walk distance, and muscular strength and endurance (secondary outcomes). Methods and Analysis: This is a single-site, single-blinded, randomized clinical trial. A minimum of 24 and maximum of 30 subjects aged 60-75 that are generally healthy but insufficiently active will be randomized. After completion of baseline assessments, participants will be randomized in a 1:1:1 ratio to participate in one of three 12-week exercise programs: stationary bicycle HIIT, stationary bicycle moderate-intensity continuous training (MICT), or resistance training. Repeat assessments will be taken immediately post intervention. Discussion: This study will examine the potential for stationary bicycle HIIT to result in both cardiorespiratory and muscular adaptations in older adults. The results will provide important insights into the effectiveness of interval training, and potentially support a shift from volume-driven to intensity-driven exercise strategies for older adults. Clinical Trial Registration: This trial is registered with ClinicalTrials.gov (registration number: NCT03978572, date of registration June 7, 2019).

Sarcopenic obesity can be negatively associated with active physical activity and adequate intake of some nutrients in Korean elderly: Findings from the Korea National Health and Nutrition Examination Survey (2008-2011)

BACKGROUND/OBJECTIVES

The aim of this study was to analyze the factors related to sarcopenic obesity among the elderly in South Korea.

SUBJECTS/METHODS

A total of 3,367 elderly (≥ 65 years) from the Korea National Health and Nutrition Examination Survey (2008–2011) were included in this analysis. The subjects were assessed to determine their sarcopenia and obesity status. Sarcopenia was assessed by determining their appendicular skeletal muscle mass (ASM). Obesity was defined by the waist circumference. An association of sarcopenic obesity and the related factors was analyzed using multiple logistic regression models.

RESULTS

The risk of sarcopenic obesity of the subjects was decreased by active physical activity. After adjusting for age, smoking, and alcohol consumption, the risk of sarcopenic obesity in men of the highest level group (Q4) decreased by 45% (OR = 0.550, 95% CI = 0.334–0.905, P trend 0.018) compared to that in the reference group (Q1). Among the women, the risk of sarcopenic obesity in the Q3 and Q4 groups decreased by 29.0% (OR = 0.710, 95% CI = 0.512–0,984) and 56.7% (OR = 0.433, 95% CI = 0.281–0.668), respectively, compared to that in the Q1 group (P trend < 0.001). The mean daily energy intake was higher in the non-sarcopenia group than in the sarcopenia group. The risk of sarcopenic obesity in subjects not meeting the recommended intakes of energy, riboflavin, and vitamin C increased significantly by 25.4%, and 36.6%, and 32.6%, respectively, compared to that in the subjects meeting the recommended nutrient intake.

CONCLUSION

Active physical activity as well as an adequate intake of energy and some vitamins might be negatively associated with the development of sarcopenia and sarcopenic obesity in the elderly.

Effects of a progressive walking program on the risk of developing locomotive syndrome in elderly Japanese people: a single-arm trial

[Purpose] This study aimed to identify the efficacy of a progressive walking program on the risk of developing locomotive syndrome among untrained elderly Japanese people. [Participants and Methods] Twenty-four untrained elderly individuals (68 ± 4 years) completed a 17-week progressive walking program. The stand-up, two-step tests and the 25-question geriatric locomotive function scale were used to assess the risk of locomotive syndrome at baseline, the 8-week midpoint (2 months), and the 17-week endpoint (4 months). Maximal isometric muscle strength of the knee extensors and flexors were measured using a dynamometer with the hip joint angle at 90° of flexion and physical function (the 30-s sit-to-stand, sit-up, 10-meter walk, and grip strength) were evaluated. [Results] The 4-month walking program significantly improved the two-step test and geriatric locomotive function scale scores. This may be attributable to the improvement in knee flexor strength and physical function. [Conclusion] A 4-month program of progressive walking effectively lowered the risk of developing locomotive syndrome in elderly Japanese people by improving knee flexor muscle strength and physical function.

Similar acute physiological responses from effort and duration matched leg press and recumbent cycling tasks

The present study examined the effects of exercise utilising traditional resistance training (leg press) or ‘cardio’ exercise (recumbent cycle ergometry) modalities upon acute physiological responses. Nine healthy males underwent a within session randomised crossover design where they completed both the leg press and recumbent cycle ergometer conditions. Conditions were approximately matched for effort and duration (leg press: 4 × 12RM using a 2 s concentric and 3 s eccentric repetition duration controlled with a metronome, thus each set lasted  60 s; recumbent cycle ergometer: 4 × 60 s bouts using a resistance level permitting 80–100 rpm but culminating with being unable to sustain the minimum cadence for the final 5–10 s). Measurements included VO₂, respiratory exchange ratio (RER), blood lactate, energy expenditure, muscle swelling, and electromyography. Perceived effort was similar between conditions and thus both were well matched with respect to effort. There were no significant effects by ‘condition’ in any of the physiological responses examined (all p > 0.05). The present study shows that, when both effort and duration are matched, resistance training (leg press) and ‘cardio’ exercise (recumbent cycle ergometry) may produce largely similar responses in VO₂, RER, blood lactate, energy expenditure, muscle swelling, and electromyography. It therefore seems reasonable to suggest that both may offer a similar stimulus to produce chronic physiological adaptations in outcomes such as cardiorespiratory fitness, strength, and hypertrophy. Future work should look to both replicate the study conducted here with respect to the same, and additional physiological measures, and rigorously test the comparative efficacy of effort and duration matched exercise of differing modalities with respect to chronic improvements in physiological fitness.

The Role of Inflammation in Age-Related Sarcopenia

Many physiological changes occur with aging. These changes often, directly or indirectly, result in a deterioration of the quality of life and even in a shortening of life expectancy. Besides increased levels of reactive oxygen species, DNA damage and cell apoptosis, another important factor affecting the aging process involves a systemic chronic low-grade inflammation. This condition has already been shown to be interrelated with several (sub)clinical conditions, such as insulin resistance, atherosclerosis and Alzheimer's disease. Recent evidence, however, shows that chronic low-grade inflammation also contributes to the loss of muscle mass, strength and functionality, referred to as sarcopenia, as it affects both muscle protein breakdown and synthesis through several signaling pathways. Classic interventions to counteract age-related muscle wasting mainly focus on resistance training and/or protein supplementation to overcome the anabolic inflexibility from which elderly suffer. Although the elderly benefit from these classic interventions, the therapeutic potential of anti-inflammatory strategies is of great interest, as these might add up to/support the anabolic effect of resistance exercise and/or protein supplementation. In this review, the molecular interaction between inflammation, anabolic sensitivity and muscle protein metabolism in sarcopenic elderly will be addressed.

Efficacy of blood flow restriction exercise during dialysis for end stage kidney disease patients: protocol of a randomised controlled trial

BACKGROUND

Exercise during haemodialysis improves strength and physical function. However, both patients and clinicians are time poor, and current exercise recommendations add an excessive time burden making exercise a rare addition to standard care. Hypothetically, blood flow restriction exercise performed during haemodialysis can provide greater value for time spent exercising, reducing this time burden while producing similar or greater outcomes. This study will explore the efficacy of blood flow restriction exercise for enhancing strength and physical function among haemodialysis patients.

METHODS

This is a randomised controlled trial design. A total of 75 participants will be recruited from haemodialysis clinics. Participants will be allocated to a blood flow restriction cycling group, traditional cycling group or usual care control group. Both exercising groups will complete 3 months of cycling exercise, performed intradialytically, three times per week. The blood flow restriction cycling group will complete two 10-min cycling bouts separated by a 20-min rest at a subjective effort of 15 on a 6 to 20 rating scale. This will be done with pressurised cuffs fitted proximally on the active limbs during exercise at 50% of a pre-determined limb occlusion pressure. The traditional cycling group will perform a continuous 20-min bout of exercise at a subjective effort of 12 on the same subjective effort scale. These workloads and volumes are equivalent and allow for comparison of a common blood flow restriction aerobic exercise prescription and a traditional aerobic exercise prescription. The primary outcome measures are lower limb strength, assessed by a three repetition maximum leg extension test, as well as objective measures of physical function: six-minute walk test, 30-s sit to stand, and timed up and go. Secondary outcome measures include thigh muscle cross sectional area, body composition, routine pathology, quality of life, and physical activity engagement.

DISCUSSION

This study will determine the efficacy of blood flow restriction exercise among dialysis patients for improving key physiological outcomes that impact independence and quality of life, with reduced burden on patients. This may have broader implications for other clinical populations with similarly declining muscle health and physical function, and those contraindicated to higher intensities of exercise.

TRIAL REGISTRATION

Australian and New Zealand Clinical Trial Register: ACTRN12616000121460.