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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 -
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 -
Genes Nov 2022Polymorphism (rs1805086), , () of the myostatin gene () has been associated with a skeletal muscle phenotype (hypertrophic response in muscles due to strength training).... (Meta-Analysis)
Meta-Analysis Review
Polymorphism (rs1805086), , () of the myostatin gene () has been associated with a skeletal muscle phenotype (hypertrophic response in muscles due to strength training). However, there are not enough reliable data to demonstrate whether rs1805086 K and R allelic variants are valid genetic factors that can affect the strength phenotype of athletes' skeletal muscles. The aim is to conduct a systematic review and meta-analysis of the association of rs1805086 polymorphism with the strength phenotype of athletes. This study analyzed 71 research articles on and performed a meta-analysis of rs1805086 polymorphism in strength-oriented athletes and a control (non-athletes) group. It was found that athletes in the strength-oriented athlete group had a higher frequency of the minor variant than that in the control group (OR = 2.02, = 0.05). Thus, the obtained results convincingly demonstrate that there is an association between the studied polymorphism and strength phenotype of athletes; therefore, further studies on this association are scientifically warranted.
Topics: Myostatin; Genotype; Polymorphism, Genetic; Muscle, Skeletal; Mutation
PubMed: 36360291
DOI: 10.3390/genes13112055 -
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 -
International Journal of Environmental... Oct 2022Reviews focused on the ketogenic diet (KD) based on the increase in fat-free mass (FFM) have been carried out with pathological populations or, failing that, without... (Meta-Analysis)
Meta-Analysis Review
Reviews focused on the ketogenic diet (KD) based on the increase in fat-free mass (FFM) have been carried out with pathological populations or, failing that, without population differentiation. The aim of this review and meta-analysis was to verify whether a ketogenic diet without programmed energy restriction generates increases in fat-free mass (FFM) in resistance-trained participants. We evaluated the effect of the ketogenic diet, in conjunction with resistance training, on fat-free mass in trained participants. Boolean algorithms from various databases (PubMed, Scopus. and Web of Science) were used, and a total of five studies were located that related to both ketogenic diets and resistance-trained participants. In all, 111 athletes or resistance-trained participants (87 male and 24 female) were evaluated in the studies analyzed. We found no significant differences between groups in the FFM variables, and more research is needed to perform studies with similar ketogenic diets and control diet interventions. Ketogenic diets, taking into account the possible side effects, can be an alternative for increasing muscle mass as long as energy surplus is generated; however, their application for eight weeks or more without interruption does not seem to be the best option due to the satiety and lack of adherence generated.
Topics: Athletes; Diet, Ketogenic; Female; Humans; Hypertrophy; Male; Muscles; Resistance Training
PubMed: 36231929
DOI: 10.3390/ijerph191912629 -
Sports Medicine (Auckland, N.Z.) Jan 2023Velocity loss (VL) experienced in a set during resistance training is often monitored to control training volume and quantify acute fatigue responses. Accordingly,... (Meta-Analysis)
Meta-Analysis
The Acute and Chronic Effects of Implementing Velocity Loss Thresholds During Resistance Training: A Systematic Review, Meta-Analysis, and Critical Evaluation of the Literature.
BACKGROUND
Velocity loss (VL) experienced in a set during resistance training is often monitored to control training volume and quantify acute fatigue responses. Accordingly, various VL thresholds are used to prescribe resistance training and target different training adaptations. However, there are inconsistencies in the current body of evidence regarding the magnitude of the acute and chronic responses to the amount of VL experienced during resistance training.
OBJECTIVE
The aim of this systematic review was to (1) evaluate the acute training volume, neuromuscular, metabolic, and perceptual responses to the amount of VL experienced during resistance training; (2) synthesize the available evidence on the chronic effects of different VL thresholds on training adaptations; and (3) provide an overview of the factors that might differentially influence the magnitude of specific acute and chronic responses to VL during resistance training.
METHODS
This review was performed using the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines. Five databases were searched, and studies were included if they were written in English, prescribed resistance training using VL, and evaluated at least one (1) acute training volume, neuromuscular, metabolic, or perceptual response or (2) training adaptation. Risk of bias was assessed using a modified Cochrane Collaboration's tool for assessing the risk of bias in randomized trials. Multilevel and multivariate meta-regressions were performed where possible.
RESULTS
Eighteen acute and 19 longitudinal studies met the inclusion criteria, of which only one had more than one risk of bias item assessed as high risk. Based on the included acute studies, it seems that the number of repetitions per set, blood lactate concentration, and rating of perceived exertion generally increase, while countermovement jump height, running sprint times, and velocity against fixed loads generally decrease as VL increases. However, the magnitude of these effects seems to be influenced, among other factors, by the exercise and load used. Regarding training adaptations, VL experienced during resistance training did not influence muscle strength and endurance gains. Increases in VL were associated with increases in hypertrophy (b = 0.006; 95% confidence interval [CI] 0.001, 0.012), but negatively affected countermovement jump (b = - 0.040; 95% CI - 0.079, - 0.001), sprint (b = 0.001; 95% CI 0.001, 0.002), and velocity against submaximal load performance (b = - 0.018; 95% CI - 0.029, - 0.006).
CONCLUSIONS
A graded relationship exists between VL experienced during a set and acute training volume, neuromuscular, metabolic, and perceptual responses to resistance training. However, choice of exercise, load, and individual trainee characteristics (e.g., training history) seem to modulate these relationships. The choice of VL threshold does not seem to affect strength and muscle endurance gains whereas higher VL thresholds are superior for enhancing hypertrophy, and lower VL thresholds are superior for jumping, sprinting, and velocity against submaximal loads performance.
CLINICAL TRIAL REGISTRATION
The original protocol was prospectively registered ( https://osf.io/q4acs/ ) with the Open Science Framework.
Topics: Humans; Athletic Performance; Resistance Training; Exercise; Running; Adaptation, Physiological; Muscle Strength
PubMed: 36178597
DOI: 10.1007/s40279-022-01754-4 -
Journal of Cachexia, Sarcopenia and... Oct 2022One aspect of skeletal muscle memory is the ability of a previously trained muscle to hypertrophy more rapidly following a period of detraining. Although the molecular... (Meta-Analysis)
Meta-Analysis Review
One aspect of skeletal muscle memory is the ability of a previously trained muscle to hypertrophy more rapidly following a period of detraining. Although the molecular basis of muscle memory remains to be fully elucidated, one potential mechanism thought to mediate muscle memory is the permanent retention of myonuclei acquired during the initial phase of hypertrophic growth. However, myonuclear permanence is debated and would benefit from a meta-analysis to clarify the current state of the field for this important aspect of skeletal muscle plasticity. The objective of this study was to perform a meta-analysis to assess the permanence of myonuclei associated with changes in physical activity and ageing. When available, the abundance of satellite cells (SCs) was also considered given their potential influence on changes in myonuclear abundance. One hundred forty-seven peer-reviewed articles were identified for inclusion across five separate meta-analyses; (1-2) human and rodent studies assessed muscle response to hypertrophy; (3-4) human and rodent studies assessed muscle response to atrophy; and (5) human studies assessed muscle response with ageing. Skeletal muscle hypertrophy was associated with higher myonuclear content that was retained in rodents, but not humans, with atrophy (SMD = -0.60, 95% CI -1.71 to 0.51, P = 0.29, and MD = 83.46, 95% CI -649.41 to 816.32, P = 0.82; respectively). Myonuclear and SC content were both lower following atrophy in humans (MD = -11, 95% CI -0.19 to -0.03, P = 0.005, and SMD = -0.49, 95% CI -0.77 to -0.22, P = 0.0005; respectively), although the response in rodents was affected by the type of muscle under consideration and the mode of atrophy. Whereas rodent myonuclei were found to be more permanent regardless of the mode of atrophy, atrophy of ≥30% was associated with a reduction in myonuclear content (SMD = -1.02, 95% CI -1.53 to -0.51, P = 0.0001). In humans, sarcopenia was accompanied by a lower myonuclear and SC content (MD = 0.47, 95% CI 0.09 to 0.85, P = 0.02, and SMD = 0.78, 95% CI 0.37-1.19, P = 0.0002; respectively). The major finding from the present meta-analysis is that myonuclei are not permanent but are lost during periods of atrophy and with ageing. These findings do not support the concept of skeletal muscle memory based on the permanence of myonuclei and suggest other mechanisms, such as epigenetics, may have a more important role in mediating this aspect of skeletal muscle plasticity.
Topics: Animals; Atrophy; Humans; Hypertrophy; Muscle Fibers, Skeletal; Muscle, Skeletal; Sarcopenia
PubMed: 35961635
DOI: 10.1002/jcsm.13043 -
Frontiers in Physiology 2022Blood flow restriction exercise (BFRE) has become a common method to increase skeletal muscle strength and hypertrophy for individuals with a variety of conditions. A...
Blood flow restriction exercise (BFRE) has become a common method to increase skeletal muscle strength and hypertrophy for individuals with a variety of conditions. A substantial literature of BFRE in older adults exists in which significant gains in strength and functional performance have been observed without report of adverse events. Research examining the effects of BFRE in heart disease (HD) and heart failure (HF) appears to be increasing for which reason the Muscle Hypothesis of Chronic Heart Failure (MHCHF) will be used to fully elucidate the effects BFRE may have in patients with HD and HF highlighted in the MHCHF. A comprehensive literature review was performed in PubMed and the Cochrane library through February 2022. Inclusion criteria were: 1) the study was original research conducted in human subjects older than 18 years of age and diagnosed with either HD or HF, 2) study participants performed BFRE, and 3) post-intervention outcome measures of cardiovascular function, physical performance, skeletal muscle function and structure, and/or systemic biomarkers were provided. Exclusion criteria included review articles and articles on viewpoints and opinions of BFRE, book chapters, theses, dissertations, and case study articles. Seven BFRE studies in HD and two BFRE studies in HF were found of which four of the HD and the two HF studies examined a variety of measures reflected within the MHCHF over a period of 8-24 weeks. No adverse events were reported in any of the studies and significant improvements in skeletal muscle strength, endurance, and work as well as cardiorespiratory performance, mitochondrial function, exercise tolerance, functional performance, immune humoral function, and possibly cardiac performance were observed in one or more of the reviewed studies. In view of the above systematic review, BFRE has been performed safely with no report of adverse event in patients with a variety of different types of HD and in patients with HF. The components of the MHCHF that can be potentially improved with BFRE include left ventricular dysfunction, inflammatory markers, inactivity, a catabolic state, skeletal and possibly respiratory muscle myopathy, dyspnea and fatigue, ANS activity, and peripheral blood flow. Furthermore, investigation of feasibility, acceptability, adherence, adverse effects, and symptoms during and after BFRE is needed since very few studies have examined these important issues comprehensively in patients with HD and HF.
PubMed: 35874535
DOI: 10.3389/fphys.2022.924557 -
Frontiers in Physiology 2022To examine the effect of plyometric jump training on skeletal muscle hypertrophy in healthy individuals. A systematic literature search was conducted in the databases...
To examine the effect of plyometric jump training on skeletal muscle hypertrophy in healthy individuals. A systematic literature search was conducted in the databases PubMed, SPORTDiscus, Web of Science, and Cochrane Library up to September 2021. Fifteen studies met the inclusion criteria. The main overall finding (44 effect sizes across 15 clusters median = 2, range = 1-15 effects per cluster) indicated that plyometric jump training had small to moderate effects [standardised mean difference (SMD) = 0.47 (95% CIs = 0.23-0.71); < 0.001] on skeletal muscle hypertrophy. Subgroup analyses for training experience revealed trivial to large effects in non-athletes [SMD = 0.55 (95% CIs = 0.18-0.93); = 0.007] and trivial to moderate effects in athletes [SMD = 0.33 (95% CIs = 0.16-0.51); = 0.001]. Regarding muscle groups, results showed moderate effects for the knee extensors [SMD = 0.72 (95% CIs = 0.66-0.78), < 0.001] and equivocal effects for the plantar flexors [SMD = 0.65 (95% CIs = -0.25-1.55); = 0.143]. As to the assessment methods of skeletal muscle hypertrophy, findings indicated trivial to small effects for prediction equations [SMD = 0.29 (95% CIs = 0.16-0.42); < 0.001] and moderate-to-large effects for ultrasound imaging [SMD = 0.74 (95% CIs = 0.59-0.89); < 0.001]. Meta-regression analysis indicated that the weekly session frequency moderates the effect of plyometric jump training on skeletal muscle hypertrophy, with a higher weekly session frequency inducing larger hypertrophic gains [β = 0.3233 (95% CIs = 0.2041-0.4425); < 0.001]. We found no clear evidence that age, sex, total training period, single session duration, or the number of jumps per week moderate the effect of plyometric jump training on skeletal muscle hypertrophy [β = -0.0133 to 0.0433 (95% CIs = -0.0387 to 0.1215); = 0.101-0.751]. Plyometric jump training can induce skeletal muscle hypertrophy, regardless of age and sex. There is evidence for relatively larger effects in non-athletes compared with athletes. Further, the weekly session frequency seems to moderate the effect of plyometric jump training on skeletal muscle hypertrophy, whereby more frequent weekly plyometric jump training sessions elicit larger hypertrophic adaptations.
PubMed: 35832484
DOI: 10.3389/fphys.2022.888464 -
Frontiers in Physiology 2022Thoracic outlet syndrome (TOS) is a rare and heterogeneous syndrome secondary to a compression of the neurovascular bundle in the thoracic outlet area. Muscle...
Thoracic outlet syndrome (TOS) is a rare and heterogeneous syndrome secondary to a compression of the neurovascular bundle in the thoracic outlet area. Muscle hypertrophy is recognized to induce vascular or neurogenic compression, especially in sports involving upper-arm solicitation. Athletes represent a distinctive population because of a specific management due to an ambitious objective, which is returning to high-level competition. We evaluated the scientific literature available for the management of TOS in athletes. Article research extended to March 2021 without other restriction concerning the date of articles publication. The search was performed independently by two assessors. A first preselection based on the article titles was produced, regarding their availability in English or French and a second preselection was produced after reading the abstracts. In case of doubt, a third assessor's advice was asked. Case reports were selected only if the sport involved was documented, as well as the level of practice. Cohorts were included if data about the number and the sport level of athletes were detailed. Seventy-eight articles were selected including 40 case reports, 10 clinical studies and 28 reviews of literature. Baseball pitchers seem to be highly at risk of developing a TOS. The surgical management appears particularly frequent in this specific population. The prognosis of TOS in athletes seems to be better than in the general population, possibly due to their better physical condition and their younger age. Some studies showed interesting and encouraging results concerning return to previous sport level. Literature shows a strong link between TOS and certain sports. Unfortunately, this syndrome still lacks rigorous diagnostic criteria and management guidelines for athletes.
PubMed: 35755427
DOI: 10.3389/fphys.2022.838014