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The Journal of Sports Medicine and... Aug 2022The aim of this study was to compare changes in muscle size, strength, and power between free-weight and machine-based exercises. (Meta-Analysis)
Meta-Analysis
INTRODUCTION
The aim of this study was to compare changes in muscle size, strength, and power between free-weight and machine-based exercises.
EVIDENCE ACQUISITION
The online databases of Pubmed, Scopus, and Web of Science were each searched using the following terms: "free weights" OR barbells OR dumbbells AND machines" up until September 15, 2020. A three-level random effects meta-analytic model was used to compute effect sizes.
EVIDENCE SYNTHESIS
When strength was tested using a free-weight exercise, individuals training with free-weights gained more strength than those training with machines (ES: 0.655; [95% CI: 0.269, 1.041]). When strength was tested a machine-based exercise incorporated as part of the machine-based training program, individuals training with machines gained more strength than those training with free-weights (ES: -0.784 [95% CI: -1.223, -0.344]). When strength was tested using a neutral device, machines and free-weight exercises resulted in similar strength gains (ES: 0.128 [95% CI: -0303, 0.559]). There were no differences in the change in power (ES: -0.049 [95% CI: -0.557, 0.460]) or muscle hypertrophy (ES: -0.01 [95% CI: -0.525, 0.545]) between exercise modes.
CONCLUSIONS
Individuals looking to increase strength and power should consider the specificity of exercise, and how their strength and power will be tested and applied. Individuals looking to increase general strength and muscle mass to maintain health may choose whichever activity they prefer and are more likely to adhere to.
Topics: Exercise; Exercise Therapy; Humans; Muscle Strength; Muscle, Skeletal; Resistance Training
PubMed: 34609100
DOI: 10.23736/S0022-4707.21.12929-9 -
Chronobiology International Apr 2019The present paper endeavored to elucidate the topic on the effects of morning versus evening resistance training on muscle strength and hypertrophy by conducting a... (Meta-Analysis)
Meta-Analysis
The present paper endeavored to elucidate the topic on the effects of morning versus evening resistance training on muscle strength and hypertrophy by conducting a systematic review and a meta-analysis of studies that examined time of day-specific resistance training. This systematic review was performed in accordance with the Preferred Reporting Items for Systematic Reviews and Meta-Analyses guidelines with searches conducted through PubMed/MEDLINE, Scopus, and SPORTDiscus databases. The Downs and Black checklist was used for the assessment of the methodological quality of the included studies. Studies that examined the effects of time of day-specific resistance training (while equating all other training variables, such as training frequency and volume, between the groups) on muscle strength and/or muscle size were included in the present review. The random effects model was used for the meta-analysis. Meta-analyses explored (1) the differences in strength expression between morning and evening hours at baseline; (2) the differences in strength within the groups training in the morning and evening by using their post-intervention strength data from the morning and evening strength assessments; (3) the overall differences between the effects of morning and evening resistance training (with subgroup analyses conducted for studies that assessed strength in the morning hours and for the studies that assessed strength in the evening hours). Finally, a meta-analysis was also conducted for studies that assessed muscle hypertrophy. Eleven studies of moderate and good methodological quality were included in the present review. The primary findings of the review are as follows: (1) at baseline, a significant difference in strength between morning and evening is evident, with greater strength observed in the evening hours; (2) resistance training in the morning hours may increase strength assessed in the morning to similar levels as strength assessed in the evening; (3) training in the evening hours, however, maintains the general difference in strength across the day, with greater strength observed in the evening hours; (4) when comparing the effects between the groups training in the morning versus in the evening hours, increases in strength are similar in both groups, regardless of the time of day at which strength assessment is conducted; and (5) increases in muscle size are similar irrespective of the time of day at which the training is performed.
Topics: Adaptation, Physiological; Circadian Rhythm; Humans; Muscle Strength; Muscle, Skeletal; Resistance Training
PubMed: 30704301
DOI: 10.1080/07420528.2019.1567524 -
Journal of Strength and Conditioning... Apr 2021Vieira, AF, Umpierre, D, Teodoro, JL, Lisboa, SC, Baroni, BM, Izquierdo, M, and Cadore, EL. Effects of resistance training performed to failure or not to failure on... (Meta-Analysis)
Meta-Analysis
Vieira, AF, Umpierre, D, Teodoro, JL, Lisboa, SC, Baroni, BM, Izquierdo, M, and Cadore, EL. Effects of resistance training performed to failure or not to failure on muscle strength, hypertrophy, and power output: A systematic review with meta-analysis. J Strength Cond Res 35(4): 1165-1175, 2021-The aim of this review was to summarize the evidence from longitudinal studies assessing the effects induced by resistance training (RT) performed to failure (RTF) vs. not to failure (RTNF) on muscle strength, hypertrophy, and power output in adults. Three electronic databases were searched using terms related to RTF and RTNF. Studies were eligible if they met the following criteria: randomized and nonrandomized studies comparing the effects of RTF vs. RTNF on muscle hypertrophy, maximal strength, and muscle power in adults, and RT intervention ≥6 weeks. Results were presented as standardized mean differences (SMDs) between treatments with 95% confidence intervals, and calculations were performed using random effects models. Significance was accepted when p < 0.05. Thirteen studies were included in this review. No difference was found between RTF and RTNF on maximal strength in overall analysis (SMD: -0.08; p = 0.642), but greater strength increase was observed in RTNF considering nonequalized volumes (SMD: -0.34; p = 0.048). Resistance training performed to failure showed a greater increase in muscle hypertrophy than RTNF (SMD: 0.75; p = 0.005), whereas no difference was observed considering equalized RT volumes. No difference was found between RTF and RTNF on muscle power considering overall analysis (SMD: -0.20; p = 0.239), whereas greater improvement was observed in RTNF considering nonequalized RT volumes (SMD: -0.61; p = 0.025). Resistance training not to failure may induce comparable or even greater improvements in maximal dynamic strength and power output, whereas no difference between RTF vs. RTNF is observed on muscle hypertrophy, considering equalized RT volumes.
Topics: Adult; Humans; Hypertrophy; Muscle Strength; Muscle, Skeletal; Resistance Training
PubMed: 33555822
DOI: 10.1519/JSC.0000000000003936 -
PloS One 2021Rheumatoid arthritis(RA) and osteoarthritis(OA) patients showed systemic manifestations that may lead to a reduction in muscle strength, muscle mass and, consequently,...
The effects of resistance training with blood flow restriction on muscle strength, muscle hypertrophy and functionality in patients with osteoarthritis and rheumatoid arthritis: A systematic review with meta-analysis.
INTRODUCTION
Rheumatoid arthritis(RA) and osteoarthritis(OA) patients showed systemic manifestations that may lead to a reduction in muscle strength, muscle mass and, consequently, to a reduction in functionality. On the other hand, moderate intensity resistance training(MIRT) and high intensity resistance training(HIRT) are able to improve muscle strength and muscle mass in RA and OA without affecting the disease course. However, due to the articular manifestations caused by these diseases, these patients may present intolerance to MIRT or HIRT. Thus, the low intensity resistance training combined with blood flow restriction(LIRTBFR) may be a new training strategy for these populations.
OBJECTIVE
To perform a systematic review with meta-analysis to verify the effects of LIRTBFR on muscle strength, muscle mass and functionality in RA and OA patients.
MATERIALS AND METHODS
A systematic review with meta-analysis of randomized clinical trials(RCTs), published in English, between 1957-2021, was conducted using MEDLINE(PubMed), Embase and Cochrane Library. The methodological quality was assessed using Physiotherapy Evidence Database scale. The risk of bias was assessed using RoB2.0. Mean difference(MD) or standardized mean difference(SMD) and 95% confidence intervals(CI) were pooled using a random-effects model. A P<0.05 was considered statistically significant.
RESULTS
Five RCTs were included. We found no significant differences in the effects between LIRTBFR, MIRT and HIRT on muscle strength, which was assessed by tests of quadriceps strength(SMD = -0.01[-0.57, 0.54], P = 0.96; I² = 58%) and functionality measured by tests with patterns similar to walking(SMD = -0.04[-0.39, 0.31], P = 0.82; I² = 0%). Compared to HIRT, muscle mass gain after LIRTBFR was reported to be similar. When comparing LIRTBFR with low intensity resistance training without blood flow restriction(LIRT), the effect LIRTBFR was reported to be higher on muscle strength, which was evaluated by the knee extension test.
CONCLUSION
LIRTBFR appears to be a promising strategy for gains in muscle strength, muscle mass and functionality in a predominant sample of RA and OA women.
Topics: Arthritis, Rheumatoid; Blood Flow Restriction Therapy; Hemodynamics; Humans; Hypertrophy; Muscle Strength; Resistance Training
PubMed: 34758045
DOI: 10.1371/journal.pone.0259574 -
Journal of Strength and Conditioning... Mar 2021Baz-Valle, E, Fontes-Villalba, M, and Santos-Concejero, J. Total number of sets as a training volume quantification method for muscle hypertrophy: A systematic review. J...
Baz-Valle, E, Fontes-Villalba, M, and Santos-Concejero, J. Total number of sets as a training volume quantification method for muscle hypertrophy: A systematic review. J Strength Cond Res 35(3): 870-878, 2021-This review aimed to determine whether assessing the total number of sets is a valid method to quantify training volume in the context of hypertrophy training. A literature search on 2 databases (PubMed and Scopus) was conducted on May 18, 2018. After analyzing 2,585 resultant articles, studies were included if they met the following criteria: (a) studies were randomized controlled trials, (b) studies compared the total number of sets, repetition range, or training frequency, (c) interventions lasted at least 6 weeks, (d) subjects had a minimum of 1 year of resistance training experience, (e) subjects' age ranged from 18 to 35 years, (f) studies reported morphologic changes through direct or indirect assessment methods, (g) studies involved subjects with no known medical conditions, and (h) studies were published in peer-reviewed journals. Fourteen studies met the inclusion criteria. According to the results of this review, the total number of sets to failure, or near to, seems to be an adequate method to quantify training volume when the repetition range lies between 6 and 20+ if all the other variables are kept constant. This approach requires further development to assess whether specific numbers of sets are key to inducing optimal muscle gains.
Topics: Adolescent; Adult; Humans; Hypertrophy; Muscle Strength; Muscle, Skeletal; Randomized Controlled Trials as Topic; Research Design; Resistance Training; Young Adult
PubMed: 30063555
DOI: 10.1519/JSC.0000000000002776 -
European Journal of Heart Failure Dec 2022An algorithm for non-invasive diagnosis of amyloid transthyretin cardiac amyloidosis (ATTR-CA) and novel disease-modifying therapies have prompted an active search for... (Meta-Analysis)
Meta-Analysis
AIMS
An algorithm for non-invasive diagnosis of amyloid transthyretin cardiac amyloidosis (ATTR-CA) and novel disease-modifying therapies have prompted an active search for CA. We examined the prevalence of CA in different settings based on literature data.
METHODS AND RESULTS
We performed a systematic search for screening studies on CA, focusing on the prevalence, sex and age distribution in different clinical settings. The prevalence of CA in different settings was as follows: bone scintigraphy for non-cardiac reasons (n = 5 studies), 1% (95% confidence interval [CI] 0%-1%); heart failure with preserved ejection fraction (n = 6), 12% (95% CI 6%-20%); heart failure with reduced or mildly reduced ejection fraction (n = 2), 10% (95% CI 6%-15%); conduction disorders warranting pacemaker implantation (n = 1), 2% (95% CI 0%-4%); surgery for carpal tunnel syndrome (n = 3), 7% (95% CI 5%-10%); hypertrophic cardiomyopathy phenotype (n = 2), 7% (95% CI 5%-9%); severe aortic stenosis (n = 7), 8% (95% CI 5%-13%); autopsy series of 'unselected' elderly individuals (n = 4), 21% (95% CI 7%-39%). The average age of CA patients in the different settings ranged from 74 to 90 years, and the percentage of men from 50% to 100%. Many patients had ATTR-CA, but the average percentage of patients with amyloid light-chain (AL) CA was up to 18%.
CONCLUSIONS
Searching for CA in specific settings allows to identify a relatively high number of cases who may be eligible for treatment if the diagnosis is unequivocal. ATTR-CA accounts for many cases of CA across the different settings, but AL-CA is not infrequent. Median age at diagnosis falls in the eighth or ninth decades, and many patients diagnosed with CA are women.
Topics: Female; Male; Humans; Heart Failure; Amyloidosis; Amyloid; Phenotype; Ventricular Dysfunction, Left; Cardiomyopathies
PubMed: 35509173
DOI: 10.1002/ejhf.2532 -
Sports Medicine (Auckland, N.Z.) Jan 2024Resistance exercise training is widely used by general and athletic populations to increase skeletal muscle hypertrophy, power and strength. Endogenous sex hormones... (Meta-Analysis)
Meta-Analysis
The Effect of Hormonal Contraceptive Use on Skeletal Muscle Hypertrophy, Power and Strength Adaptations to Resistance Exercise Training: A Systematic Review and Multilevel Meta-analysis.
BACKGROUND
Resistance exercise training is widely used by general and athletic populations to increase skeletal muscle hypertrophy, power and strength. Endogenous sex hormones influence various bodily functions, including possibly exercise performance, and may influence adaptive changes in response to exercise training. Hormonal contraceptive (HC) use modulates the profile of endogenous sex hormones, and therefore, there is increasing interest in the impact, if any, of HC use on adaptive responses to resistance exercise training.
OBJECTIVE
Our aim is to provide a quantitative synthesis of the effect of HC use on skeletal muscle hypertrophy, power and strength adaptations in response to resistance exercise training.
METHODS
A systematic review with meta-analysis was conducted on experimental studies which directly compared skeletal muscle hypertrophy, power and strength adaptations following resistance exercise training in hormonal contraceptive users and non-users conducted before July 2023. The search using the online databases PUBMED, SPORTDiscus, Web of Science, Embase and other supplementary search strategies yielded 4669 articles, with 8 articles (54 effects and 325 participants) meeting the inclusion criteria. The methodological quality of the included studies was assessed using the "Tool for the assessment of study quality and reporting in exercise".
RESULTS
All included studies investigated the influence of oral contraceptive pills (OCP), with no study including participants using other forms of HC. The articles were analysed using a meta-analytic multilevel maximum likelihood estimator model. The results indicate that OCP use does not have a significant effect on hypertrophy [0.01, 95% confidence interval (CI) [- 0.11, 0.13], t = 0.14, p = 0.90), power (- 0.04, 95% CI [- 0.93, 0.84], t = - 0.29, p = 0.80) or strength (0.10, 95% CI [- 0.08, 0.28], t = 1.48, p = 0.20).
DISCUSSION
Based on the present analysis, there is no evidence-based rationale to advocate for or against the use of OCPs in females partaking in resistance exercise training to increase hypertrophy, power and/or strength. Rather, an individualised approach considering an individual's response to OCPs, their reasons for use and menstrual cycle history may be more appropriate.
REGISTRATION
The review protocol was registered on PROSPERO (ID number and hyperlink: CRD42022365677).
Topics: Female; Humans; Contraceptives, Oral; Gonadal Steroid Hormones; Hypertrophy; Muscle Strength; Muscle, Skeletal; Resistance Training
PubMed: 37755666
DOI: 10.1007/s40279-023-01911-3 -
Archives of Disease in Childhood Oct 2016Leukaemia is the most common cancer of childhood, accounting for a third of cases. In order to assist clinicians in its early detection, we systematically reviewed all... (Meta-Analysis)
Meta-Analysis Review
OBJECTIVE
Leukaemia is the most common cancer of childhood, accounting for a third of cases. In order to assist clinicians in its early detection, we systematically reviewed all existing data on its clinical presentation and estimated the frequency of signs and symptoms presenting at or prior to diagnosis.
DESIGN
We searched MEDLINE and EMBASE for all studies describing presenting features of leukaemia in children (0-18 years) without date or language restriction, and, when appropriate, meta-analysed data from the included studies.
RESULTS
We screened 12 303 abstracts for eligibility and included 33 studies (n=3084) in the analysis. All were cohort studies without control groups. 95 presenting signs and symptoms were identified and ranked according to frequency. Five features were present in >50% of children: hepatomegaly (64%), splenomegaly (61%), pallor (54%), fever (53%) and bruising (52%). An additional eight features were present in a third to a half of children: recurrent infections (49%), fatigue (46%), limb pain (43%), hepatosplenomegaly (42%), bruising/petechiae (42%), lymphadenopathy (41%), bleeding tendency (38%) and rash (35%). 6% of children were asymptomatic on diagnosis.
CONCLUSIONS
Over 50% of children with leukaemia have palpable livers, palpable spleens, pallor, fever or bruising on diagnosis. Abdominal symptoms such as anorexia, weight loss, abdominal pain and abdominal distension are common. Musculoskeletal symptoms such as limp and joint pain also feature prominently. Children with unexplained illness require a thorough history and focused clinical examination, which should include abdominal palpation, palpation for lymphadenopathy and careful scrutiny of the skin. Occurrence of multiple symptoms and signs should alert clinicians to possible leukaemia.
Topics: Abdominal Pain; Adolescent; Child; Child, Preschool; Contusions; Early Detection of Cancer; Exanthema; Fever; Gastrointestinal Diseases; Hemorrhage; Hepatomegaly; Humans; Infant; Infant, Newborn; Infections; Leukemia; Musculoskeletal Diseases; Recurrence; Skin Diseases; Splenomegaly
PubMed: 27647842
DOI: 10.1136/archdischild-2016-311251 -
Journal of Strength and Conditioning... Sep 2017Schoenfeld, BJ, Ogborn, DI, Vigotsky, AD, Franchi, MV, and Krieger, JW. Hypertrophic effects of concentric vs. eccentric muscle actions: A systematic review and... (Meta-Analysis)
Meta-Analysis Review
Schoenfeld, BJ, Ogborn, DI, Vigotsky, AD, Franchi, MV, and Krieger, JW. Hypertrophic effects of concentric vs. eccentric muscle actions: A systematic review and meta-analysis. J Strength Cond Res 31(9): 2599-2608, 2017-Controversy exists as to whether different dynamic muscle actions produce divergent hypertrophic responses. The purpose of this paper was to conduct a systematic review and meta-analysis of randomized controlled trials comparing the hypertrophic effects of concentric vs. eccentric training in healthy adults after regimented resistance training (RT). Studies were deemed eligible for inclusion if they met the following criteria: (a) were an experimental trial published in an English-language refereed journal; (b) directly compared concentric and eccentric actions without the use of external implements (i.e., blood pressure cuffs) and all other RT variables equivalent; (c) measured morphologic changes using biopsy, imaging (magnetic resonance imaging, computerized tomography, or ultrasound), bioelectrical impedance, and/or densitometry; (d) had a minimum duration of 6 weeks; and (e) used human participants without musculoskeletal injury or any health condition that could directly, or through the medications associated with the management of said condition, be expected to impact the hypertrophic response to resistance exercise. A systematic literature search determined that 15 studies met inclusion criteria. Results showed that eccentric muscle actions resulted in a greater effect size (ES) compared with concentric actions, but results did not reach statistical significance (ES difference = 0.25 ± 0.13; 95% confidence interval: -0.03 to 0.52; p = 0.076). The mean percent change in muscle growth across studies favored eccentric compared with concentric actions (10.0% vs. 6.8, respectively). The findings indicate the importance of including eccentric and concentric actions in a hypertrophy-oriented RT program, as both have shown to be effective in increasing muscle hypertrophy.
Topics: Adult; Biopsy; Electric Impedance; Exercise; Female; Humans; Magnetic Resonance Imaging; Male; Muscle, Skeletal; Randomized Controlled Trials as Topic; Resistance Training
PubMed: 28486337
DOI: 10.1519/JSC.0000000000001983 -
Journal of Strength and Conditioning... May 2020Roberts, BM, Nuckols, G, and Krieger, JW. Sex differences in resistance training: A systematic review and meta-analysis. J Strength Cond Res 34(5): 1448-1460, 2020-The... (Meta-Analysis)
Meta-Analysis
Roberts, BM, Nuckols, G, and Krieger, JW. Sex differences in resistance training: A systematic review and meta-analysis. J Strength Cond Res 34(5): 1448-1460, 2020-The purpose of this study was to determine whether there are different responses to resistance training for strength or hypertrophy in young to middle-aged males and females using the same resistance training protocol. The protocol was pre-registered with PROSPERO (CRD42018094276). Meta-analyses were performed using robust variance random effects modeling for multilevel data structures, with adjustments for small samples using package robumeta in R. Statistical significance was set at P < 0.05. The analysis of hypertrophy comprised 12 outcomes from 10 studies with no significant difference between males and females (effect size [ES] = 0.07 ± 0.06; P = 0.31; I = 0). The analysis of upper-body strength comprised 19 outcomes from 17 studies with a significant effect favoring females (ES = -0.60 ± 0.16; P = 0.002; I = 72.1). The analysis of lower-body strength comprised 23 outcomes from 23 studies with no significant difference between sexes (ES = -0.21 ± 0.16; P = 0.20; I = 74.7). We found that males and females adapted to resistance training with similar effect sizes for hypertrophy and lower-body strength, but females had a larger effect for relative upper-body strength. Given the moderate effect size favoring females in the upper-body strength analysis, it is possible that untrained females display a higher capacity to increase upper-body strength than males. Further research is required to clarify why this difference occurs only in the upper body and whether the differences are due to neural, muscular, motor learning, or are an artifact of the short duration of studies included.
Topics: Adult; Female; Humans; Hypertrophy; Male; Middle Aged; Muscle Strength; Muscle, Skeletal; Resistance Training; Sex Characteristics; Time Factors; Young Adult
PubMed: 32218059
DOI: 10.1519/JSC.0000000000003521