-
European Journal of Sport Science May 2018Currently, it is unclear whether manipulation of movement velocity during resistance exercise has an effect on hypertrophy of specific muscles. The purpose of this... (Review)
Review
Currently, it is unclear whether manipulation of movement velocity during resistance exercise has an effect on hypertrophy of specific muscles. The purpose of this systematic review of literature was to investigate the effect of movement velocity during resistance training on muscle hypertrophy. Five electronic databases were searched using terms related to movement velocity and resistance training. Inclusion criteria were randomised and non-randomised comparative studies; published in English; included healthy adults; used dynamic resistance exercise interventions directly comparing fast training to slower movement velocity training; matched in prescribed intensity and volume; duration ≥4 weeks; and measured muscle hypertrophy. A total of six studies were included involving 119 untrained participants. Hypertrophy of the quadriceps was examined in five studies and of the biceps brachii in two studies. Three studies found significantly greater increases in hypertrophy of the quadriceps for moderate-slow compared to fast training. For the remaining studies examining the quadriceps, significant within-group increase in hypertrophy was found for only moderate-slow training in one study and for only fast training in the other study. The two studies that examined hypertrophy of the biceps brachii found greater increases for fast compared to moderate-slow training. Caution is required when interpreting the findings from this review due to the low number of studies, hence insufficient data. Future longitudinal randomised controlled studies in cohorts of healthy adults are required to confirm and extend our findings.
Topics: Humans; Hypertrophy; Muscle Strength; Muscle, Skeletal; Randomized Controlled Trials as Topic; Resistance Training
PubMed: 29431597
DOI: 10.1080/17461391.2018.1434563 -
American Journal of Translational... 2021MicroRNAs (miRNAs) are small non-coding RNAs that participate in gene expression regulation. It has been observed that circulating levels of miRNAs may fluctuate during... (Review)
Review
MicroRNAs (miRNAs) are small non-coding RNAs that participate in gene expression regulation. It has been observed that circulating levels of miRNAs may fluctuate during exercise, showing numerous cardiac biological and physiological effects such as structural and functional adaptations. We aimed to provide an overview of the currently available information concerning the role of circulating miRNAs in cardiovascular adaptations in response to acute and/or chronic exercise training. Relevant studies published were searched in three databases: PubMed, Web of Science and Scopus. A combination of the following keywords was used: ("microRNA" OR "miRNA" OR "miR" AND "exercise" OR "training" OR "physical activity") AND "(heart hypertrophy" OR "cardiac remodeling" OR "cardiac muscle mass" OR "cardiac hypertrophy"). Only experimental studies, written in English and conducted in healthy individuals were included. Five articles met the inclusion criteria and were finally included in this systematic review after reviewing both title, abstract and full-text. A total of thirty-six circulating cardiac-related miRNAs were analyzed, but only five of them (miR-1, miR-133a, miR-146a, miR-206 and miR-221) were directly associated with cardiac adaptations parameters, while two of them (miR-1 and miR-133a) were related to cardiac hypertrophy. Most of them were upregulated immediately after a marathon and returned to basal levels at longer times. Therefore, we conclude that, although evidence is still limited, and long-term studies are needed to obtain more robust evidence, exercise is more likely to affect circulating cardiac-related miRNAs levels.
PubMed: 35035676
DOI: No ID Found -
Annals of Plastic Surgery Feb 2023Energy-based treatments include ultrasound, lasers, cryolipolysis, and radiofrequency. The most recent energy treatment for noninvasive body contouring is...
BACKGROUND
Energy-based treatments include ultrasound, lasers, cryolipolysis, and radiofrequency. The most recent energy treatment for noninvasive body contouring is electromagnetic treatments-a hot topic in plastic surgery today. A systematic review to assess efficacy and safety has not been published.
METHODS
An electronic search was performed using PubMed to identify the literature describing electromagnetic treatments. Measurements from imaging studies were tabulated and compared.
RESULTS
Fourteen clinical studies were evaluated. Two studies included simultaneous radiofrequency treatments. In 11 studies, the Emsculpt device was used; in 2 studies, the Emsculpt-Neo device was used. One study included a sham group of patients. The usual protocol was 4 treatments given over a 2-week period. No complications were reported. Eight studies included abdominal measurement data obtained using magnetic resonance imaging, computed tomography, or ultrasound. Photographic results were typically modest. Photographs showing more dramatic results also showed unexplained reductions in untreated areas.Measurement variances were high. The mean reduction in fat thickness was 5.5 mm. The mean increment in muscle thickness was 2.2 mm. The mean decrease in muscle separation was 2.9 mm (P = 0.19). Early posttreatment ultrasound images in 1 study showed an echolucent muscle layer, compared with a more echodense layer at the baseline, consistent with tissue swelling after exercise. Almost all studies were authored by medical advisors for the device manufacturer.
DISCUSSION
Measurement data show small reductions in fat thickness, occurring almost immediately after the treatments. Adipocyte removal without tissue swelling would be unique among energy-based treatments. Similarly, muscle hypertrophy is not known to occur acutely after exercise; muscle swelling likely accounts for an early increment in muscle thickness. Any improvement in the diastasis recti is likely fictitious.
CONCLUSIONS
Electromagnetic treatments, either administered alone or in combination with radiofrequency, are safe. However, the evidence for efficacy is tenuous. Measured treatment effects are very small (<5 mm). Conflict of interest and publication bias are major factors in studies evaluating energy-based alternatives. The evidence-based physician may not be satisfied that an equivocal treatment benefit justifies the time and expense for patients.
Topics: Humans; Body Contouring; Follow-Up Studies; Patient Satisfaction; Lipectomy; Electromagnetic Phenomena
PubMed: 36688862
DOI: 10.1097/SAP.0000000000003387 -
Sports Medicine - Open Apr 2024Increases in maximal strength and muscle volume represent central aims of training interventions. Recent research suggested that the chronic application of stretch may...
BACKGROUND
Increases in maximal strength and muscle volume represent central aims of training interventions. Recent research suggested that the chronic application of stretch may be effective in inducing hypertrophy. The present systematic review therefore aimed to syntheisize the evidence on changes of strength and muscle volume following chronic static stretching.
METHODS
Three data bases were sceened to conduct a systematic review with meta-analysis. Studies using randomized, controlled trials with longitudinal (≥ 2 weeks) design, investigating strength and muscle volume following static stretching in humans, were included. Study quality was rated by two examiners using the PEDro scale.
RESULTS
A total of 42 studies with 1318 cumulative participants were identified. Meta-analyses using robust variance estimation showed small stretch-mediated maximal strength increases (d = 0.30 p < 0.001) with stretching duration and intervention time as significant moderators. Including all studies, stretching induced small magnitude, but significant hypertrophy effects (d = 0.20). Longer stretching durations and intervention periods as well as higher training frequencies revealed small (d = 0.26-0.28), but significant effects (p < 0.001-0.005), while lower dosage did not reach the level of significance (p = 0.13-0.39).
CONCLUSIONS
While of minor effectiveness, chronic static stretching represents a possible alternative to resistance training when aiming to improve strength and increase muscle size. As a dose-response relationship may exist, higher stretch durations and frequencies as well as long program durations should be further elaborated.
PubMed: 38637473
DOI: 10.1186/s40798-024-00706-8 -
Journal of Functional Morphology and... Apr 2023Emerging evidence indicates that the use of low-load resistance training in combination with blood flow restriction (LL-BFR) can be an effective method to elicit... (Review)
Review
Emerging evidence indicates that the use of low-load resistance training in combination with blood flow restriction (LL-BFR) can be an effective method to elicit increases in muscle size, with most research showing similar whole muscle development of the extremities compared to high-load (HL) training. It is conceivable that properties unique to LL-BFR such as greater ischemia, reperfusion, and metabolite accumulation may enhance the stress on type I fibers during training compared to the use of LLs without occlusion. Accordingly, the purpose of this paper was to systematically review the relevant literature on the fiber-type-specific response to LL-BFR and provide insights into future directions for research. A total of 11 studies met inclusion criteria. Results of the review suggest that the magnitude of type I fiber hypertrophy is at least as great, and sometimes greater, than type II hypertrophy when performing LL-BFR. This finding is in contrast to HL training, where the magnitude of type II fiber hypertrophy tends to be substantially greater than that of type I myofibers. However, limited data directly compare training with LL-BFR to nonoccluded LL or HL conditions, thus precluding the ability to draw strong inferences as to whether the absolute magnitude of type I hypertrophy is indeed greater in LL-BFR vs. traditional HL training. Moreover, it remains unclear as to whether combining LL-BFR with traditional HL training may enhance whole muscle hypertrophy via greater increases in type I myofiber cross-sectional area.
PubMed: 37218848
DOI: 10.3390/jfmk8020051 -
Journal of Sport and Health Science Mar 2022One of the most life-threatening comorbidities in elderly cancer patients is cancer cachexia, which is characterized by the ongoing loss of skeletal muscular strength... (Meta-Analysis)
Meta-Analysis Review
BACKGROUND
One of the most life-threatening comorbidities in elderly cancer patients is cancer cachexia, which is characterized by the ongoing loss of skeletal muscular strength and mass and is also associated with aging. There is a lack of recommendations for optimal resistance training (RT) for those patients. The purpose of this study was to systematically review and quantify the effects of RT on muscular strength and hypertrophy in elderly cancer patients.
METHODS
Five electronic databases were searched (until January 2020) for studies that met the following criteria: (i) cancer patients aged ≥60 years; (ii) structured and supervised RT intervention for ≥6 weeks; and (iii) measured muscular strength and/or hypertrophy.
RESULTS
Thirteen studies (717 participants, average age = 66 years) met the inclusion criteria. RT significantly increased muscular strength (mean effect size = 0.87, 95% confidence interval (95%CI): 0.43-1.32, p < 0.001) and did not significantly induce muscle hypertrophy (mean effect size = 0.09, 95%CI: -0.14 to 0.31, p = 0.45). In subgroup analyses for muscle strength, higher weekly frequency was significantly associated with larger effect size. Egger's test showed no significant publication bias for the 2 outcomes.
CONCLUSION
The results suggest that RT improves muscular strength but does not significantly induce muscle hypertrophy in elderly cancer patients.
Topics: Aged; Humans; Hypertrophy; Middle Aged; Muscle Strength; Muscle, Skeletal; Neoplasms; Resistance Training
PubMed: 33592324
DOI: 10.1016/j.jshs.2021.02.002 -
Journal of Clinical Medicine Dec 2022There is clinical interest in determining the effects of low-load blood flow restriction (LL-BFR) resistance training on muscle strength and hypertrophy compared with... (Review)
Review
Effects of Low-Load Blood Flow Restriction Resistance Training on Muscle Strength and Hypertrophy Compared with Traditional Resistance Training in Healthy Adults Older Than 60 Years: Systematic Review and Meta-Analysis.
BACKGROUND
There is clinical interest in determining the effects of low-load blood flow restriction (LL-BFR) resistance training on muscle strength and hypertrophy compared with traditional high- and low-load (HL and LL) resistance training in healthy older adults and the influence of LL-BFR training cuff-pressure on these outcomes.
METHODS
A search was performed on the MEDLINE, PEDro, CINHAL, Web of Science, Science Direct, Scopus, and CENTRAL databases.
RESULTS
The analysis included 14 studies. HL resistance training produces a small increase in muscle strength (eight studies; SMD, -0.23 [-0.41; -0.05]) but not in muscle hypertrophy (six studies; (SMD, 0.08 [-0.22; 0.38]) when compared with LL-BFR resistance training. Compared with traditional LL resistance training, LL-BFR resistance training produces small-moderate increases in muscle strength (seven studies; SMD, 0.44 [0.28; 0.60]) and hypertrophy (two studies; SMD, 0.51 [0.06; 0.96]). There were greater improvements in muscle strength when higher cuff pressures were applied versus traditional LL resistance training but not versus HL resistance training.
CONCLUSIONS
LL-BFR resistance training results in lower muscle strength gains than HL resistance training and greater than traditional LL resistance training in healthy adults older than 60 years. LL-BFR resistance training promotes a similar muscle hypertrophy to HL resistance training but is greater than that of traditional LL resistance training. Applying cuff pressures above the limb occlusion pressure could enhance the increases in muscle strength compared with traditional LL resistance training.
PubMed: 36556004
DOI: 10.3390/jcm11247389 -
Healthcare (Basel, Switzerland) Aug 2021Combined training (CT) may combine strength and endurance training within a given time period, but it can also encompass additional protocols consisting of velocity,... (Review)
Review
Combined training (CT) may combine strength and endurance training within a given time period, but it can also encompass additional protocols consisting of velocity, balance, or mobility as part of the same intervention. These combined approaches have become more common in soccer. This systematic review was conducted to (1) characterize the training protocols used in CT studies in soccer, (2) summarize the main physiological and physical effects of CT on soccer players, and (3) provide future directions for research. Methods: A systematic review of Cochrane Library, PubMed, Scopus, SPORTDiscus, and Web of Science databases was performed according to the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines. The PICOS were defined as follows: P (soccer players of any age or sex); I (CT combining strength and endurance or sprinting or balance or mobility training); C (the control group (whenever applicable), with or without comparative interventions in addition to usual soccer training); O (acute and/or chronic responses: biochemical, physiological and physical); S (must have at least two groups, either randomized or non-randomized). The database search initially identified 79 titles. From those, eight articles were deemed eligible for the systematic review. Three studies analyzed acute responses to concurrent training, while the remaining five analyzed adaptations to CT. In those tested for acute responses, physiological (hormonal) and physical (strength and power external load, internal load) parameters were observed. Adaptations were mainly focused on physical parameters (strength and power, sprints, jumps, repeated sprint ability, aerobic, change-of-direction), with relatively little focus on physiological parameters (muscle architecture). Short-term responses to CT can affect hormonal responses of testosterone after resistance training with internal and external load. In turn, these responses' effects on strength and power have produced mixed results, as have adaptations. Specifically, strength and hypertrophy are affected to a lesser extent than speed/power movements. Nevertheless, it is preferable to perform CT before endurance exercises since it is a limiting factor for interference. Volume, intensity, rest between sessions, and athletes' fitness levels and nutrition dictate the degree of interference.
PubMed: 34442212
DOI: 10.3390/healthcare9081075 -
Translational Sports Medicine 2023Trained individuals may require variations in training stimuli and advanced resistance training paradigms (ADV) to increase skeletal muscle hypertrophy. However, no... (Review)
Review
Trained individuals may require variations in training stimuli and advanced resistance training paradigms (ADV) to increase skeletal muscle hypertrophy. However, no meta-analysis has examined how ADV versus traditional (TRAD) approaches may differentially affect hypertrophic outcomes in trained populations. The aim of this review was to determine whether the skeletal muscle hypertrophy responses induced by TRAD differed from ADV in resistance-trained individuals. Furthermore, we sought to examine potential effects of dietary factors, participants' training status, and training loads. We searched for peer-reviewed, randomized controlled trials (published in English) conducted in healthy resistance-trained adults performing a period of TRAD and ADV with pre-to-post measurement(s) of muscle hypertrophy in PubMed, Web of Science, SPORTDiscus, and MEDLINE databases up to October 2022. A formal meta-analysis was conducted in Revman5, and risk of bias was assessed by ROB2. Ten studies met the inclusion criteria. Results indicated no difference between ADV and TRAD for muscle thickness (SMD = 0.05, 95% CI: -0.20 0.29, = 0.70), lean mass (SMD = -0.01, 95% CI: -0.26 0.23, = 0.92), muscle cross-sectional area (SMD = -0.07, 95% CI: -0.36 0.22, = 0.64), or all measurements analyzed together (SMD = -0.00, 95% CI: -0.15 0.14, = 0.95). No heterogeneity or inconsistencies were observed; however, unclear risk of bias was present in most of the studies. Short-term ADV does not induce superior skeletal muscle hypertrophy responses when compared with TRAD in trained individuals. This review was not previously registered.
PubMed: 38654909
DOI: 10.1155/2023/9507977 -
Journal of Exercise Science and Fitness Jan 2024This study aims to compare, through quantitative analysis, the effectiveness of different endurance training types on increasing lower limb strength and muscle... (Review)
Review
OBJECTIVE
This study aims to compare, through quantitative analysis, the effectiveness of different endurance training types on increasing lower limb strength and muscle cross-sectional area (MCSA) in concurrent training.
METHODS
This systematic literature search was performed according to the Preferred Reporting Items for Systematic Reviews and Meta-Analysis (PRISMA) [PROSPERO ID: CRD42023396886]. Web of Science, SportDiscuss, Pubmed, Cochrane, and Scopus were systematically searched from their inception date to October 20, 2023.
RESULTS
A total of 40 studies (841 participants) were included in this meta-analysis. MCSA analysis showed that, compared to resistance training alone, concurrent high-intensity interval running training and resistance training and concurrent moderate-intensity continuous cycling training and resistance training were more effective (SMD = 0.15, 95% CI = -0.46 to 0.76, and SMD = 0.07, 95% CI = -0.24 to 0.38 respectively), while other modalities of concurrent training not. Lower body maximal strength analysis showed that all modalities of concurrent training were inferior to resistance training alone, but concurrent high-intensity interval training and resistance training showed an advantage in four different concurrent training modalities (SMD = -0.08, 95% CI = -0.25 to 0.08). For explosive strength, only concurrent high-intensity interval training and resistance training was superior to resistance training (SMD = 0.06, 95% CI = -0.21 to 0.33).
CONCLUSION
Different endurance training types have an impact on the effectiveness of concurrent training, particularly on lower limb strength. Adopting high-intensity interval running as the endurance training type in concurrent training can effectively minimize the adverse effects on lower limb strength and MCSA.
PubMed: 38187085
DOI: 10.1016/j.jesf.2023.12.005