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British Journal of Sports Medicine Sep 2023To determine how distinct combinations of resistance training prescription (RTx) variables (load, sets and frequency) affect muscle strength and hypertrophy. (Meta-Analysis)
Meta-Analysis
OBJECTIVE
To determine how distinct combinations of resistance training prescription (RTx) variables (load, sets and frequency) affect muscle strength and hypertrophy.
DATA SOURCES
MEDLINE, Embase, Emcare, SPORTDiscus, CINAHL, and Web of Science were searched until February 2022.
ELIGIBILITY CRITERIA
Randomised trials that included healthy adults, compared at least 2 predefined conditions (non-exercise control (CTRL) and 12 RTx, differentiated by load, sets and/or weekly frequency), and reported muscle strength and/or hypertrophy were included.
ANALYSES
Systematic review and Bayesian network meta-analysis methodology was used to compare RTxs and CTRL. Surface under the cumulative ranking curve values were used to rank conditions. Confidence was assessed with threshold analysis.
RESULTS
The strength network included 178 studies (n=5097; women=45%). The hypertrophy network included 119 studies (n=3364; women=47%). All RTxs were superior to CTRL for muscle strength and hypertrophy. Higher-load (>80% of single repetition maximum) prescriptions maximised strength gains, and all prescriptions comparably promoted muscle hypertrophy. While the calculated effects of many prescriptions were similar, higher-load, multiset, thrice-weekly training (standardised mean difference (95% credible interval); 1.60 (1.38 to 1.82) vs CTRL) was the highest-ranked RTx for strength, and higher-load, multiset, twice-weekly training (0.66 (0.47 to 0.85) vs CTRL) was the highest-ranked RTx for hypertrophy. Threshold analysis demonstrated these results were extremely robust.
CONCLUSION
All RTx promoted strength and hypertrophy compared with no exercise. The highest-ranked prescriptions for strength involved higher loads, whereas the highest-ranked prescriptions for hypertrophy included multiple sets.
PROSPERO REGISTRATION NUMBER
CRD42021259663 and CRD42021258902.
Topics: Humans; Adult; Female; Resistance Training; Bayes Theorem; Network Meta-Analysis; Muscle, Skeletal; Muscle Strength; Hypertrophy; Prescriptions
PubMed: 37414459
DOI: 10.1136/bjsports-2023-106807 -
Parkinson's disease and intensive exercise therapy - An updated systematic review and meta-analysis.Acta Neurologica Scandinavica May 2022In 2015, Uhrbrand et al. published the first review on Parkinson´s disease (PD) and exercise entirely based on randomized controlled trials (RCT) applying strict... (Meta-Analysis)
Meta-Analysis Review
In 2015, Uhrbrand et al. published the first review on Parkinson´s disease (PD) and exercise entirely based on randomized controlled trials (RCT) applying strict exercise definitions. The present review aimed to update the PD literature by assessing the effects of different intensive exercise modalities: resistance training (RT), endurance training (ET), and other intensive exercise modalities (OITM). An updated systematic literature search identified 33 new RCTs. Qualitative and quantitative analyses were performed. A total of 18 RT, 14 ET, and 1 OITM studies were identified (adding to the 8 RT, 6 ET, and 4 OITM studies identified by Uhrbrand et al. in 2015). RT, ET, and OITM were feasible, safe, and did not worsen PD symptoms. Furthermore, RT, ET, and OITM may positively affect functional outcomes (e.g., balance) and depressive symptoms in PD but inconsistencies across these findings warrant cautious conclusions. Meta-analyses showed that RT had a positive impact on muscle strength (standardized mean difference (SMD) = 0.83 [95% CI;0.54, 1.12]), functional capacity (Timed Up and Go Test (TUG): SMD = -0.62 [-1.01, -0.24]), and quality of life (SMD = -0.41 [-0.72, -0.09]), while ET had a positive impact on cardiorespiratory fitness (SMD = 0.27 [0.07, 0.47]) and functional capacity (TUG: SMD = -0.21 [-0.46, 0.04], 6-Min Walk Test: SMD = 0.89 [0.17, 1.62]), and a potentially positive impact on "on-medication" UPDRS-III (SMD = -0.15 [-0.38, 0.09]) and "off-medication" UPDRS-III (SMD = -0.19 [-0.41, 0.04]). In conclusion, RT, ET, and OITM all represent safe, feasible, and beneficial adjunct rehabilitation strategies in PD, with particularly RT and ET showing solid effects.
Topics: Exercise; Exercise Therapy; Humans; Muscle Strength; Parkinson Disease; Resistance Training
PubMed: 34997759
DOI: 10.1111/ane.13579 -
Magnesium Research Nov 2017Increasing evidence supports a role of magnesium (Mg) in skeletal muscle function. However, no systematic review or meta-analysis has summarized data on Mg... (Meta-Analysis)
Meta-Analysis Review
Increasing evidence supports a role of magnesium (Mg) in skeletal muscle function. However, no systematic review or meta-analysis has summarized data on Mg supplementation in relation to muscle fitness in humans. Thus, this study aimed to quantitatively assess the effect of Mg supplementation on muscle fitness. A meta-analysis and systematic review. Medline database and other sources were searched for randomized clinical trials through July 2017. Studies that reported results regarding at least one of the following outcomes: leg strength, knee extension strength, peak torque, muscle power, muscle work, jump, handgrip, bench press weights, resistant exercise, lean mass, muscle mass, muscle strength, walking speed, Repeated Chair Stands, and TGUG were included. Measurements of the association were pooled using a fixed-effects model and expressed as weighted mean differences (WMDs) with 95% confidence intervals (95% CIs). Fourteen randomized clinical trials targeting 3 different populations were identified: athletes or physically active individuals (215 participants; mean age: 24.9 years), untrained healthy individuals (95 participants; mean age: 40.2 years), and elderly or alcoholics (232 participants; mean age: 62.7 years). The beneficial effects of Mg supplementation appeared to be more pronounced in the elderly and alcoholics, but were not apparent in athletes and physically active individuals. The results of the meta-analysis suggested that no significant improvements in the supplementation group were observed regarding isokinetic peak torque extension [WMD = 0.87; 95% CI = (-1.43, 3.18)], muscle strength [WMD = 0.87; 95% CI = (-0.12, 1.86)] or muscle power [WMD = 3.28; 95% CI = (-14.94, 21.50)]. Evidence does not support a beneficial effect of Mg supplementation on muscle fitness in most athletes and physically active individuals who have a relatively high Mg status. But Mg supplementation may benefit individuals with Mg deficiency, such as the elderly and alcoholics.
Topics: Adult; Aged; Alcoholism; Athletes; Dietary Supplements; Exercise; Female; Humans; Magnesium; Male; Muscle Strength
PubMed: 29637897
DOI: 10.1684/mrh.2018.0430 -
International Journal of Environmental... Nov 2022Resistance training is considered to be an efficient treatment for age-related sarcopenia and can improve muscle strength and quality in patients. However, there are... (Meta-Analysis)
Meta-Analysis Review
Resistance training is considered to be an efficient treatment for age-related sarcopenia and can improve muscle strength and quality in patients. However, there are currently no recommendations on resistance training parameters to improve muscle strength and quality in elderly patients with sarcopenia. We conducted a systematic review and meta-analysis of randomized controlled trials (RCTs) and included 13 eligible RCTs. Resistance training significantly improved grip strength, gait speed, and skeletal muscle index in patients with age-related sarcopenia, and kettlebell was found to be the most effective modality. However, it is noteworthy that the elastic band is also a recommended form of resistance training considering that the kettlebell intervention was tested in only one study, while the elastic band was confirmed by multiple studies. Elastic band training (Hedges's g = 0.629, 95%CI = 0.090-1.168, < 0.05) (40-60 min per session, more than three times per week for at least 12 weeks) was the most efficient training method. Thus, resistance training can significantly improve muscle strength and muscle quality in elderly patients with sarcopenia. In addition, moderate-intensity resistance training using elastic bands may be the best training prescription for elderly patients with sarcopenia.
Topics: Humans; Aged; Resistance Training; Sarcopenia; Muscle Strength; Muscle, Skeletal; Hand Strength
PubMed: 36497565
DOI: 10.3390/ijerph192315491 -
Journal of the International Society of... 2018Caffeine is commonly used as an ergogenic aid. Literature about the effects of caffeine ingestion on muscle strength and power is equivocal. The aim of this systematic... (Meta-Analysis)
Meta-Analysis Review
BACKGROUND
Caffeine is commonly used as an ergogenic aid. Literature about the effects of caffeine ingestion on muscle strength and power is equivocal. The aim of this systematic review and meta-analysis was to summarize results from individual studies on the effects of caffeine intake on muscle strength and power.
METHODS
A search through eight databases was performed to find studies on the effects of caffeine on: (i) maximal muscle strength measured using 1 repetition maximum tests; and (ii) muscle power assessed by tests of vertical jump. Meta-analyses of standardized mean differences (SMD) between placebo and caffeine trials from individual studies were conducted using the random effects model.
RESULTS
Ten studies on the strength outcome and ten studies on the power outcome met the inclusion criteria for the meta-analyses. Caffeine ingestion improved both strength (SMD = 0.20; 95% confidence interval [CI]: 0.03, 0.36; = 0.023) and power (SMD = 0.17; 95% CI: 0.00, 0.34; = 0.047). A subgroup analysis indicated that caffeine significantly improves upper (SMD = 0.21; 95% CI: 0.02, 0.39; = 0.026) but not lower body strength (SMD = 0.15; 95% CI: -0.05, 0.34; = 0.147).
CONCLUSION
The meta-analyses showed significant ergogenic effects of caffeine ingestion on maximal muscle strength of upper body and muscle power. Future studies should more rigorously control the effectiveness of blinding. Due to the paucity of evidence, additional findings are needed in the female population and using different forms of caffeine, such as gum and gel.
Topics: Athletes; Caffeine; Humans; Muscle Strength; Muscle, Skeletal; Performance-Enhancing Substances; Sports Nutritional Physiological Phenomena
PubMed: 29527137
DOI: 10.1186/s12970-018-0216-0 -
Journal of Bodywork and Movement... Jan 2022Spinal cord injuries (SCI) have physiological, emotional, and economic consequences in the lives of affected people. Resistance training (RT) is efficient in improving... (Meta-Analysis)
Meta-Analysis Review
INTRODUCTION
Spinal cord injuries (SCI) have physiological, emotional, and economic consequences in the lives of affected people. Resistance training (RT) is efficient in improving several physiological factors, quality of life, and body composition.
EVIDENCE ACQUISITION
Due to the scarce literature on RT analyzed separately, the objective of this systematic review is to analyze the effects of RT with no association to other techniques, in aspects related to the quality of life and body composition of people The research for the articles was carried out in the Pubmed, Cochrane, and Web of Science databases using the terms "Spinal cord injuries" AND "Resistance Training" OR "Strength training". Given the scarcity of evidence on the subject, no deadline was set for the study to be eligible for analysis.
EVIDENCE SYNTHESIS
The research for the articles was carried out in November of 2020 and returned 349 results, of which 220 remained after the elimination of duplicates, with 145 being excluded after title analysis. Seventy-five abstracts were analyzed and 70 studies were excluded, leaving 5 complete articles for a thorough analysis with SCI. Despite the I being 87%, the meta-analysis revealed an overall effect of Z = 4.79 (P < 0.00001).
CONCLUSIONS
After analyzing the main results, we concluded that RT is feasible, secure, and promotes significant improvements in maximum strength, local muscular endurance, power, and muscular isometric voluntary contraction in people with spinal cord injury.
Topics: Body Composition; Humans; Muscle Strength; Quality of Life; Resistance Training; Spinal Cord Injuries
PubMed: 35248264
DOI: 10.1016/j.jbmt.2021.09.031 -
Journal of Strength and Conditioning... Feb 2017Chiang, C-m, Ismaeel, A, Griffis, RB, and Weems, S. Effects of vitamin D supplementation on muscle strength in athletes: A systematic review. J Strength Cond Res 31(2):... (Review)
Review
Chiang, C-m, Ismaeel, A, Griffis, RB, and Weems, S. Effects of vitamin D supplementation on muscle strength in athletes: A systematic review. J Strength Cond Res 31(2): 566-574, 2017-The purpose of this systematic review of the literature was to investigate the effects of vitamin D supplementation on muscle strength in athletes. A computerized literature search of 3 databases (PubMed, MEDLINE, and Scopus) was performed. Included in the review were randomized controlled trials (RCTs), published in English, which measured serum vitamin D concentrations and muscle strength in healthy, athletic participants aged 18-45 years. Quality was assessed using the PEDro scale. Five RCTs and 1 controlled trial were identified, and quality assessment showed 5 trials were of "excellent quality" and 1 was of "good quality." Trials lasted from 4 weeks to 6 months and dosages ranged from 600 to 5,000 International Units (IU) per day. Vitamin D2 was found to be ineffective at impacting muscle strength in both studies wherein it was administered. In contrast, vitamin D3 was shown to have a positive impact on muscle strength. In 2 studies, strength outcome measures were significantly improved after supplementation (p ≤ 0.05). In the other 2 studies administering vitamin D3, there were trends for improved muscle strength. Specifically, improvements in strength ranged from 1.37 to 18.75%. Additional studies are needed to confirm these associations.
Topics: Adolescent; Adult; Athletes; Cholecalciferol; Controlled Clinical Trials as Topic; Dietary Supplements; Dose-Response Relationship, Drug; Ergocalciferols; Female; Humans; Male; Middle Aged; Muscle Strength; Outcome Assessment, Health Care; Vitamin D; Young Adult
PubMed: 27379960
DOI: 10.1519/JSC.0000000000001518 -
Sports Medicine (Auckland, N.Z.) Mar 2023This systematic review with meta-analysis investigated the influence of resistance training proximity-to-failure on muscle hypertrophy. (Meta-Analysis)
Meta-Analysis
BACKGROUND AND OBJECTIVE
This systematic review with meta-analysis investigated the influence of resistance training proximity-to-failure on muscle hypertrophy.
METHODS
Literature searches in the PubMed, SCOPUS and SPORTDiscus databases identified a total of 15 studies that measured muscle hypertrophy (in healthy adults of any age and resistance training experience) and compared resistance training performed to: (A) momentary muscular failure versus non-failure; (B) set failure (defined as anything other than momentary muscular failure) versus non-failure; or (C) different velocity loss thresholds.
RESULTS
There was a trivial advantage for resistance training performed to set failure versus non-failure for muscle hypertrophy in studies applying any definition of set failure [effect size=0.19 (95% confidence interval 0.00, 0.37), p=0.045], with no moderating effect of volume load (p=0.884) or relative load (p=0.525). Given the variability in set failure definitions applied across studies, sub-group analyses were conducted and found no advantage for either resistance training performed to momentary muscular failure versus non-failure for muscle hypertrophy [effect size=0.12 (95% confidence interval -0.13, 0.37), p=0.343], or for resistance training performed to high (>25%) versus moderate (20-25%) velocity loss thresholds [effect size=0.08 (95% confidence interval -0.16, 0.32), p=0.529].
CONCLUSION
Overall, our main findings suggest that (i) there is no evidence to support that resistance training performed to momentary muscular failure is superior to non-failure resistance training for muscle hypertrophy and (ii) higher velocity loss thresholds, and theoretically closer proximities-to-failure do not always elicit greater muscle hypertrophy. As such, these results provide evidence for a potential non-linear relationship between proximity-to-failure and muscle hypertrophy.
Topics: Humans; Muscle, Skeletal; Resistance Training; Muscle Strength; Hypertrophy
PubMed: 36334240
DOI: 10.1007/s40279-022-01784-y -
Journal of Sports Sciences Jun 2017The purpose of this paper was to systematically review the current literature and elucidate the effects of total weekly resistance training (RT) volume on changes in... (Meta-Analysis)
Meta-Analysis Review
The purpose of this paper was to systematically review the current literature and elucidate the effects of total weekly resistance training (RT) volume on changes in measures of muscle mass via meta-regression. The final analysis comprised 34 treatment groups from 15 studies. Outcomes for weekly sets as a continuous variable showed a significant effect of volume on changes in muscle size (P = 0.002). Each additional set was associated with an increase in effect size (ES) of 0.023 corresponding to an increase in the percentage gain by 0.37%. Outcomes for weekly sets categorised as lower or higher within each study showed a significant effect of volume on changes in muscle size (P = 0.03); the ES difference between higher and lower volumes was 0.241, which equated to a percentage gain difference of 3.9%. Outcomes for weekly sets as a three-level categorical variable (<5, 5-9 and 10+ per muscle) showed a trend for an effect of weekly sets (P = 0.074). The findings indicate a graded dose-response relationship whereby increases in RT volume produce greater gains in muscle hypertrophy.
Topics: Humans; Muscle Strength; Muscle, Skeletal; Resistance Training; Time Factors
PubMed: 27433992
DOI: 10.1080/02640414.2016.1210197 -
International Journal of Environmental... Mar 2023Strength training in prepubertal children is one of the topics that has aroused the most interest and controversy among training professionals in recent years.... (Review)
Review
Strength training in prepubertal children is one of the topics that has aroused the most interest and controversy among training professionals in recent years. Therefore, the aim of the present study was to analyze the available scientific evidence on the influence of strength training variables on morphological and/or neuromuscular adaptations in healthy prepubertal populations with no previous experience in this type of training according to the descriptive sample characteristics. According to the Preferred Reporting Items for Systematic Reviews and Meta-Analysis, 22 studies were selected after a systematic search and selection process using four electronic databases: Google Scholar, PubMed, Scopus, and SPORT Discus. Furthermore, the internal validity of the studies included was assessed using the modified PEDro scale. The sample consisted of 604 prepubertal children (age, 10.02 ± 0.75 years), of whom 473 were boys and 131 were girls, with 104 strength training programs recorded. Strength training resulted in a significant increase in jumping ( = 29) and sprinting ( = 13) abilities. Moreover, muscle strength was increased in 100% of the cases. Morphologically, strength training resulted in a decrease in body fat percentage ( = 19) and an increase in lean body mass ( = 17). With regard to gender, increases in general sport skills and basic physical abilities were significant in males but not in females. Thus, the results are more heterogeneous in girls due to the small number of studies carried out. Therefore, this research provides practical applications for coaches to design and implement more effective training programs to maximize adaptations, enhance physical performance, and reduce injury risk.
Topics: Male; Female; Humans; Child; Resistance Training; Muscle Strength; Sports; Adaptation, Physiological; Acclimatization
PubMed: 36981742
DOI: 10.3390/ijerph20064833