Effects of Eccentric-Focused Versus Conventional Training on Lower Limb Muscular Strength in Older People: A Systematic Review With Meta-Analysis

Flywheel resistance training: Functionality and strength in older women - A randomized controlled trial

BACKGROUND

Resistance training enhances functionality and strength in older populations, but the comparative effectiveness of traditional versus inertial flywheel modalities is under-researched. This study evaluates the effect of these modalities on functionality and strength in older women.

METHODS

In a parallel two-group randomized controlled trial, 36 sedentary older women (≥60 years) without psychiatric disorders or uncontrolled chronic diseases were randomly assigned to either the inertial flywheel group (n = 18) using a multi-leg isoinertial device, or the traditional resistance training group (n = 18) using gym machines and free weights. Conducted from May to December 2023 at the Federal University of Viçosa, both groups performed six generic exercises over eight weeks (two sessions per week). Functionality and muscle strength were assessed using the Short Physical Performance Battery and Timed Up and Go tests. Blinding was maintained using opaque envelopes managed by an external researcher.

RESULTS

One participant from the traditional group withdrew, requiring data imputation. Both groups showed significant improvements in functionality (Short Physical Performance Battery scores, p = 0.008; Timed Up and Go times, p = 0.025) and strength (isometric, dynamic, and explosive). No significant differences between groups were observed (p > 0.05), with small to moderate effect sizes (ηp2 = 0.01 to 0.06) and low statistical power (1-β < 0.80). Adverse events were minor (grade 1).

CONCLUSIONS

Both traditional and inertial flywheel resistance training significantly improved functionality and strength in older women over 16 sessions. Either training approach can enhance physical performance in this population.

The effects of 6-week home-based static stretching, dynamic stretching, or eccentric exercise interventions on muscle-tendon properties and functional performance in older women

Background

Joint inflexibility is acknowledged as a significant contributor to functional limitations in the older adult, with lengthening-type exercises identified as a potential remedial approach. Nevertheless, the responses to eccentric exercise in female older adults have not been extensively studied especially in home-based environment. Here, we aimed to assess the effectiveness of home-based static stretching (ST), dynamic closed-chain stretching (DCS), or eccentric exercise (ECC) interventions on flexibility, musculotendinous architecture, and functional ability in healthy older women.

Methods

We randomly assigned 51 healthy older women (age 65.9 ± 3.4 years) to one of three interventional exercise groups: DCS (N = 17), ECC (N = 17), or ST (N = 17). The training was performed 3 times a week for 6 weeks. The participants' musculotendinous stiffness, fascicle length, eccentric strength, and functional capacities were measured before the intervention, after 6 weeks of exercise, and at a 1-month follow-up.

Results

The results showed that all three interventions improved hamstring flexibility and passive ankle dorsiflexion (p < 0.001), with increased biceps femoris and medial gastrocnemius fascicle length (p < 0.01). However, there was no significant change in musculotendinous stiffness. The ECC intervention produced a greater improvement in knee flexor and calf eccentric peak torque (p < 0.05), and gait speed (p = 0.024) than the other two interventions. The changes in flexibility and knee flexor strength remained for up to 4 weeks after detraining.

Conclusion

In conclusion, the present study suggests that home-based ECC may be more beneficial in enhancing physical capacities in older women compared with either DCS or SS interventions.

Effects of ankle isokinetic training on muscle strength and balance amongst older women with mild Parkinson's disease: A randomised trial

BACKGROUND

Patients with Parkinson's disease frequently experience problems with balance and gait.

OBJECTIVE

This study examined the influences of regular ankle isokinetic muscle strength training on muscle strength and balance ability amongst elderly women with mild Parkinson's disease.

METHODS

A total of 55 elderly women with mild Parkinson's disease were randomly divided into the experimental group (n= 28) and the control group (n= 27) for 16 weeks. The experimental group was trained for 16 weeks by using isokinetic muscle strength training.

RESULTS

After 16 weeks of training in the experimental group, the peak torque (PT) of ankle (average of the left and right sides) dorsiflexion, plantarflexion, eversion and inversion, and the standing balance index revealed that the left and right stability and overall stability indexes significantly increased by 25.9%, 43.5%, 62.7%, 82.8%, 37.1% and 32.2%, respectively (p< 0.05). The experimental group exhibited significantly increased PT of ankle dorsiflexion, plantarflexion, eversion and inversion. Moreover, the left and right stability and overall stability indexes were significantly improved compared with those of the control group (p< 0.05). This study found a linear regression relationship between the PT of ankle inversion and overall stability index.

CONCLUSION

This study determined that ankle isokinetic muscle strength training improved ankle dorsiflexion, plantarflexion, eversion and inversion muscle strength, and balance ability amongst elderly women with mild Parkinson's disease. However, it did not improve stability in the anterior and posterior directions. Ankle inversion muscle strength is more likely to affect overall balance.

Preferred Reporting Items for Resistance Exercise Studies (PRIRES): A Checklist Developed Using an Umbrella Review of Systematic Reviews

BACKGROUND

The issues of replication and scientific transparency have been raised in exercise and sports science research. A potential means to address the replication crisis and enhance research reliability is to improve reporting quality and transparency. This study aims to formulate a reporting checklist as a supplement to the existing reporting guidelines, specifically for resistance exercise studies.

METHODS

PubMed (which covers Medline) and Scopus (which covers Medline, EMBASE, Ei Compendex, World Textile Index, Fluidex, Geobase, Biobase, and most journals in Web of Science) were searched for systematic reviews that comprised the primary studies directly comparing different resistance training methods. Basic data on the selected reviews, including on authors, publication years, and objectives, were summarized. The reporting items for the checklist were identified based on the objective of the reviews. Additional items from an existing checklist, namely the Consensus on Exercise Reporting Template, a National Strength and Conditioning Association handbook, and an article from the EQUATOR library were incorporated into the final reporting checklist.

RESULTS

Our database search retrieved 3595 relevant records. After automatic duplicate removal, the titles and abstracts of the remaining 2254 records were screened. The full texts of 137 records were then reviewed, and 88 systematic reviews that met the criteria were included in the umbrella review.

CONCLUSION

Developed primarily by an umbrella review method, this checklist covers the research questions which have been systematically studied and is expected to improve the reporting completeness of future resistance exercise studies. The PRIRES checklist comprises 26 reporting items (39 subitems) that cover four major topics in resistance exercise intervention: 1) exercise selection, performance, and training parameters, 2) training program and progression, 3) exercise setting, and 4) planned vs actual training. The PRIRES checklist was designed specifically for reporting resistance exercise intervention. It is expected to be used with other reporting guidelines such as Consolidated Standards of Reporting Trials and Standard Protocol Items: Recommendations for Interventional Trials. This article presents only the development process and resulting items of the checklist. An accompanying article detailing the rationale for, the importance of, and examples of each item is being prepared.

REGISTRATION

This study is registered with the EQUATOR Network under the title "Preferred Reporting Items for Resistance Exercise Studies (PRIRES)." PROSPERO registration number: CRD42021235259.

Implementation and Core Components of a Multimodal Program including Exercise and Nutrition in Prevention and Treatment of Frailty in Community-Dwelling Older Adults: A Narrative Review

Increasing disability-free life expectancy is a crucial issue to optimize active ageing and to reduce the burden of evitable medical costs. One of the main challenges is to develop pragmatic and personalized prevention strategies in order to prevent frailty, counteract adverse outcomes such as falls and mobility disability, and to improve quality of life. Strong evidence reports the effectiveness of exercise interventions to improve various physical parameters and muscle function that are cornerstones of frailty. Other findings also suggest that the interactions between nutrition and physical exercise with or without health behavior promotion prevent the development of frailty. Multimodal programs, including structured exercise, adequate dietary intervention and health behavior promotion, appear increasingly consensual. However, in order for implementation in real-life settings, some pitfalls need to be addressed. In this perspective, structuring and tailoring feasible, acceptable and sustainable interventions to optimize exercise training responses are essential conditions to warrant short, medium and long-term individual benefits. The different components of exercise programs appear to be fairly consensual and effective. However, specific composition of the programs proposed (frequency, intensity, type, time, volume and progressiveness) have to be tailored to individual characteristics and objectives in order to improve exercise responses. The intervention approaches, behavioral strategies and indications for these programs also need to be refined and framed. The main objective of this work is to guide the actions of healthcare professionals and enable them to widely and effectively implement multimodal programs including exercise, nutrition and behavioral strategies in real-life settings.

The Health and Functional Benefits of Eccentric versus Concentric Exercise Training: A Systematic Review and Meta-Analysis

This review compared the effects of eccentric versus concentric exercise training in healthy people and people with metabolic disease. A systematic search on Cochrane Central Register of Controlled Trials, MEDLINE, Embase, CINAHL, SPORTDiscus, Web of Science, SCOPUS and PubMed was conducted in February 2022. Randomised controlled trials conducted on sedentary healthy adults or those with an existing metabolic disease that compared eccentric versus concentric exercise training interventions of four weeks or longer that involved multiple joints and large muscle groups (e.g., walking, whole-body resistance training) were included in the review. The primary outcome was glucose handling, measured as HbA1c, HOMA, fasting glucose or insulin. Measures of cardiovascular health, muscle strength, and functional physical fitness were secondary outcomes. Nineteen trials involving 618 people were included. Results of meta-analyses showed that eccentric exercise had no benefit to glucose handling (HbA1c level; SMD - 0.99; 95% CI, -2.96 to 0.98; n = 74; P = 0.32) but resulted in significant increases in overall muscle strength (SMD 0.70; 95% CI 0.25 to 1.15; n = 224; P = 0.003) and decreases in blood pressure (Systolic Blood Pressure; MD -6.84; 95% CI, -9.84 to -3.84; n = 47, P = 0.00001, and Diastolic Blood Pressure; MD -6.39; 95% CI -9.62 to -3.15; n = 47, P = 0.0001). Eccentric exercise is effective for improving strength and some markers of cardiovascular health compared to traditional exercise modalities. Additional high-quality studies are necessary to validate these results. (PROSPERO registration: CRD42021232167).

Eccentric resistance training with neurological conditions: A meta analysis

BACKGROUND

People with neurological conditions are exposed to muscle wasting resulting in reduced strength and endurance. Both deficiencies negatively impact gait and balance, each of which can be benefited by strengthening exercises. Unfortunately, people with neurological conditions often do not have the ability to perform traditional weight training as their endurance and strength fail to meet the minimum threshold for improvement. An alternative to traditional, full range of motion lifting is eccentric resistance training (ERT).

RESEARCH QUESTION

The current systematic review and meta-analysis sought to evaluate the efficacy of ERT against conventional therapeutic modalities or weightlifting on walking speed, Timed Up and Go (TUG), and maximum voluntary isometric contraction (MVIC) in individuals with neurological conditions.

METHODS

Web of Science, PubMed, and Academic Search Complete were searched until September 1, 2020, followed by a manual search on December 3, 2021. Publications were included if they were peer reviewed, available in English, consisted of a pre-specified neurological disorder, involved human subjects, had an eccentric and "traditional" therapy; and reported at least one of the outcome measures at both pre- and post-intervention.

RESULTS

Thirteen studies of human subjects (n = 297) and 47 standardized mean differences (SMD) were included in the multilevel model analysis. The analysis revealed a small, albeit non-significant effect on performance (TUG, MVIC, walking speed) when comparing traditional therapies and ERT (SMD: 0.136; 96; 95 % CI: -0.0002, 0.050).

SIGNIFICANCE

There appears to be no difference between ERT and traditional therapy or weightlifting on measured outcomes. In this way, ERT is as effective as traditional therapeutics and full range of motion weightlifting to improve movement in clinical populations. Practitioners working with populations with neurological conditions may consider supplementing or replacing traditional strengthening activities with ERT as clients can complete greater volumes of work with lower metabolic demand.

The chronic effects of eccentric exercise interventions in different populations: an umbrella review

The effectiveness of eccentric exercise interventions (EEI) has been extensively explored in different populations. The aim of our umbrella review was to combine all systematic reviews about the chronic efficiency of EEI and to summarize the literature on the chronic effects of different types of eccentric exercise protocols, with or without extra loads and devices (e.g., Flywheel device), compared to other therapeutic interventions, exercise interventions, or no intervention. We screened four major electronic scientific databases (PubMed, Scopus, Web of Science, and PEDro), using one combined string for all included databases (eccentric exercise OR flywheel OR isoinertial exercise OR eccentric training). Included reviews needed to be based on any human population, that executed EEI in comparison with any other type of intervention. The methodological quality of the included reviews was assessed using AMSTAR 2 tool. Considering the inclusion criteria, we included 35 reviews. EEI were found suitable for chronic or long-term pain reduction in patient populations. EEI largely improved muscle performance (muscle strength, and muscle power), muscle architecture (e.g., pennation angle, fascicle length, cross-sectional area, muscle thickness, and muscle mass), decreased risk of injury, incidence, and severity of the injury, and increased range of motion of the joints There is less evidence about the effects of EEI in older adult populations, compared to athletes and younger populations, however, eccentric exercise seems promising for these populations as well.

The Effect of Eccentric vs. Traditional Resistance Exercise on Muscle Strength, Body Composition, and Functional Performance in Older Adults: A Systematic Review With Meta-Analysis

The effects of eccentric exercise (ECC) in older adults have received limited scientific attention, considering the ample evidence for its effectiveness in general and athletic populations. The purpose of this paper is to review the effects of ECC exercise modalities vs. traditional or concentric (CON) exercise on muscle strength, body composition and functional performance in older adults. Inclusion criteria regarding the age was >55 years. Three major scientific literature databases (PubMed, Scopus and Web of Science) were screened for trials comparing the effect of ECC and CON exercise programs, and 19 papers were included in the meta-analysis. ECC and CON training programs were typically matched by the duration of each session. The difference between ECC and CON was expressed as standardized mean difference (SMD). Regarding isometric knee strength, the pooled effect favored ECC (SMD = 0.50), but was not statistically significant (p = 0.160). ECC exercise elicited greater improvements in timed up and go test (SMD = −0.68; p = 0.004), 2-min sit-stand test (SMD = 0.53; p = 0.030) and 30-s sit-stand test (SMD = 0.81; p = 0.002), but not in 6-min walking test (SMD = 0.01; p = 0.960). The effects on body composition and muscle architecture were unclear (SMD = −1.44 to 1.95; p = 0.060–0.689). In conclusion, our literature review indicates that ECC exercise is superior to, or at least as good as CON exercise for preserving health and overall function in older adults.

Initial Muscle Quality Affects Individual Responsiveness of Interleukin-6 and Creatine Kinase following Acute Eccentric Exercise in Sedentary Obese Older Women

This study aimed to evaluate the time course and responsiveness of plasma interleukin-6 (IL-6) and creatine kinase (CK) levels following acute eccentric resistance exercise in sedentary obese older women with a different muscle quality index (MQI). Eighty-eight participants (69.4 ± 6.06 years) completed an acute eccentric resistance exercise (7 sets of 10 repetitions at 110% of 10-repetition maximum with 3 min rest interval). Participants were divided into two groups: high or low MQI according to 50th percentile cut-off. The responsiveness was based on minimal clinical important difference. There were no differences between groups and time on IL-6 and CK levels (p > 0.05). However, the high MQI group displayed a lower proportion of low responders (1 for laboratory and 2 for field-based vs. 5 and 4) and a higher proportion of high responders for IL-6 (7 for laboratory and 6 for field-based vs. 4 and 5) compared to low MQI group. In addition, the high MQI group showed a higher proportion of high responders for CK (11 for laboratory and 9 for field-based vs. 6 and 6) compared to low MQI. A prior MQI screening can provide feedback to understand the magnitude response. Individual responsiveness should be taken into consideration for maximizing eccentric exercise prescription.

Potential Benefits of a Minimal Dose Eccentric Resistance Training Paradigm to Combat Sarcopenia and Age-Related Muscle and Physical Function Deficits in Older Adults

The ability of older adults to perform activities of daily living is often limited by the ability to generate high mechanical outputs. Therefore, assessing and developing maximal neuromuscular capacity is essential for determining age-related risk for functional decline as well as the effectiveness of therapeutic interventions. Interventions designed to enhance neuromuscular capacities underpinning maximal mechanical outputs could positively impact functional performance in daily life. Unfortunately, < 10% of older adults meet the current resistance training guidelines. It has recently been proposed that a more “minimal dose” RT model may help engage a greater proportion of older adults, so that they may realize the benefits of RT. Eccentric exercise offers some promising qualities for such an approach due to its efficiency in overloading contractions that can induce substantial neuromuscular adaptations. When used in a minimal dose RT paradigm, eccentric-based RT may be a particularly promising approach for older adults that can efficiently improve muscle mass, strength, and functional performance. One approach that may lead to improved neuromuscular function capacities and overall health is through heightened exercise tolerance which would favor greater exercise participation in older adult populations. Therefore, our perspective article will discuss the implications of using a minimal dose, submaximal (i.e., low intensity) multi-joint eccentric resistance training paradigm as a potentially effective, and yet currently underutilized, means to efficiently improve neuromuscular capacities and function for older adults.