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1.
Sci Rep ; 14(1): 9176, 2024 04 22.
Artigo em Inglês | MEDLINE | ID: mdl-38649771

RESUMO

Back pain is one of the major global challenges and is one of the most prevalent musculoskeletal disorders occurring in 80% of people at least once in their lifetime. Therefore, the need to find appropriate treatment methods for this issue is very important. The objective is to examine the short-term and acute effects of a treatment session with dry needling, massage therapy, stretching exercises and Kinesio tape on pain, functional disability, position sense and range of motion in elite bodybuilders with non-specific chronic low back pain. The sample of this quasi-experimental study consisted of 48 bodybuilders with non-specific chronic low back pain (all male, mean age = 25.96 ± 2.18 years; mean weight = 74.45 ± 4.51 kg; mean height = 173.88 ± 3.74 cm; mean BMI = 24.60 ± 0.74 kg/m2) who randomly were placed in 4 dry needling, massage therapy, stretching exercises and Kinesio tape groups. The duration of each intervention was 30 min. The dependent variables in this study included the massage range of motion, position sense tests and visual pain scale that were taken separately from each subject in pretest, posttest (acute effect) and follow-up test (72 h after posttest; short-term effect). The results of a 4 (groups) × 3 (time) the mixed ANOVAs showed that pain in the short-term phase was significantly lower in the dry needling group than in the stretching and massage groups (P < 0.05). Also in the acute effect phase, the flexion range of motion was significantly lower in the dry needling group than in the massage group (P < 0.05). Furthermore, the two groups of stretching and massage exercises showed significantly greater range of motion (P < 0.05). Other comparisons were not significant (P > 0.05). The findings of the study showed that both massage and stretching treatment have higher acute effects, while dry needling treatment was more effective in follow up. On the other hand, these findings show that these treatment methods can have immediate and lasting positive effects in improving the performance in elite bodybuilders with non-specific chronic low back pain.


Assuntos
Dor Lombar , Amplitude de Movimento Articular , Humanos , Dor Lombar/terapia , Dor Lombar/fisiopatologia , Masculino , Adulto , Massagem/métodos , Dor Crônica/terapia , Dor Crônica/fisiopatologia , Exercícios de Alongamento Muscular , Levantamento de Peso , Resultado do Tratamento , Medição da Dor , Adulto Jovem
2.
J Sports Sci Med ; 22(2): 226-234, 2023 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-37293409

RESUMO

The combination of strength training with complementary whole-body electromyostimulation (WB-EMS) and plyometric exercises has been shown to increase strength and jumping performance in athletes. In elite sport, however, the mesocycles of training are often organized according to block periodization. Furthermore, WB-EMS is often applied onto static strength exercises, which may hamper the transfer into more sport-specific tasks. Thus, this study aimed at investigating whether four weeks of strength training with complementary dynamic vs. static WB-EMS followed by a four-week block of plyometric training increases maximal strength and jumping performance. A total of n = 26 (13 female/13 male) trained adults (20.8 ± 2.2 years, 69.5 ± 9.5kg, 9.7 ± 6.1h of training/w) were randomly assigned to a static (STA) or volume-, load- and work-to-rest-ratio-matched dynamic training group (DYN). Before (PRE), after four weeks (three times weekly) of WB-EMS training (MID) and a subsequent four-week block (twice weekly) of plyometric training (POST), maximal voluntary contraction (MVC) at leg extension (LE), leg curl (LC) and leg press machines (LP) and jumping performance (SJ, Squat Jump; CMJ, counter-movement-jump; DJ, drop-jump) were assessed. Furthermore, perceived effort (RPE) was rated for each set and subsequently averaged for each session. MVC at LP notably increased between PRE and POST in both STA (2335 ± 539 vs. 2653 ± 659N, standardized mean difference [SMD] = 0.528) and DYN (2483 ± 714N vs. 2885 ± 843N, SMD = 0.515). Reactive strength index of DJ showed significant differences between STA and DYN at MID (162.2 ± 26.4 vs. 123.1 ± 26.5 cm·s-1, p = 0.002, SMD = 1.478) and POST (166.1 ± 28.0 vs. 136.2 ± 31.7 cm·s-1, p = 0.02, SMD = 0.997). Furthermore, there was a significant effect for RPE, with STA rating perceived effort higher than DYN (6.76 ± 0.32 vs. 6.33 ± 0.47 a.u., p = 0.013, SMD = 1.058). When employing a training block of high-density WB-EMS both static and dynamic exercises lead to similar adaptations.


Assuntos
Terapia por Estimulação Elétrica , Treinamento Resistido , Adulto , Humanos , Masculino , Feminino , Exercício Físico/fisiologia , Terapia por Exercício , Levantamento de Peso
3.
J Strength Cond Res ; 37(5): 1079-1088, 2023 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-36165879

RESUMO

ABSTRACT: Li, J, Davies, TB, and Hackett, DA. Self-reported training and supplementation practices between performance-enhancing drug-user bodybuilders compared with natural bodybuilders. J Strength Cond Res 37(5): 1079-1088, 2023-This study aimed to examine whether the training and supplementation practices differ between performance-enhancing drug (PED)-using bodybuilders (BB) and natural BB. One hundred eighty-seven competitive male bodybuilders with a median age of 27.0 years completed an online survey. Of this sample, 40 respondents reported using PED (PED-user) and 147 respondents reported to be natural. Compared with natural BB, PED-user BB reported greater off-season body weight ( p < 0.001) and weight loss before a competition ( p < 0.001). In the off-season, PED-user BB performed a greater number of exercises per muscle group ( p < 0.001), number of repetition maximum (RM) per set ( p < 0.01), and less recovery between the sets ( p < 0.01). During the precompetition phase, the natural BB increased their number of RM; however, the PED-user BB still reported using a greater number of RM per set ( p = 0.02), exercises per muscle group ( p < 0.001), and less recovery time between the sets ( p < 0.01). Both the PED-user BB and natural BB reported greater aerobic exercise frequency ( p < 0.001) and session duration ( p < 0.001), although PED-user BB performed a greater number of aerobic exercise sessions ( p = 0.04) and at a higher intensity ( p < 0.01). Advanced training techniques, including negatives, partial repetitions, preexhaustion sets, and timed repetitions, were more popular among PED-user BB ( p < 0.05). Creatine monohydrate usage was more popular among natural BB ( p < 0.001), whereas branched-chain and essential amino acids were more popular among PED-user BB ( p ≤ 0.001). Findings suggest that PED-user BB perform more metabolically demanding resistance training sessions, more strenuous aerobic training during the precompetition phase, and may have different supplementation preferences compared with natural BB.


Assuntos
Substâncias para Melhoria do Desempenho , Treinamento Resistido , Humanos , Masculino , Adulto , Autorrelato , Levantamento de Peso/fisiologia , Exercício Físico , Treinamento Resistido/métodos , Suplementos Nutricionais , Músculo Esquelético/fisiologia , Força Muscular/fisiologia
4.
Artigo em Inglês | MEDLINE | ID: mdl-35886591

RESUMO

Mixed martial arts (MMA) athletes must achieve high strength levels to face the physical demands of an MMA fight. This study compared MMA athletes' maximal isometric and dynamic strength according to the competitive level and weight class. Twenty-one male MMA athletes were divided into lightweight professional (LWP; n = 9), lightweight elite (LWE; n = 4), heavyweight professional (HWP; n = 4), and heavyweight elite (HWE; n = 4). The handgrip and isometric lumbar strength tests assessed the isometric strength, and the one-repetition maximum (1RM) bench press and 4RM leg press the dynamic strength. Univariate ANOVA showed differences between groups in absolute and relative 1RM bench press and absolute isometric lumbar strength. Post hoc tests showed differences in 1RM bench press between HWE and LWE (117.0 ± 17.8 kg vs. 81.0 ± 10.0 kg) and HWE and LWP athletes (117.0 ± 17.8 kg vs. 76.7 ± 13.7 kg; 1.5 ± 0.2 kg·BW-1 vs. 1.1 ± 0.2 kg·BW-1). In addition, there was a correlation between 1RM bench press and isometric lumbar strength for absolute (r = 0.67) and relative values (r = 0.50). This study showed that the 1RM bench press and isometric lumbar strength were associated and could differentiate MMA athletes according to their competitive level and weight class. Therefore, optimizing the force production in the upper body and lower back seems important in elite and professional MMA athletes.


Assuntos
Artes Marciais , Força Muscular , Atletas , Força da Mão , Humanos , Masculino , Levantamento de Peso
5.
Artigo em Inglês | MEDLINE | ID: mdl-34360032

RESUMO

The aim of this research was to verify whether the application of percussion therapy during inter-set rest periods increases the number of repetitions performed before reaching a 30% velocity loss threshold during a bench press exercise. Methods: Twenty-four male university students participated in this study (24.3 ± 1.3 years; 77.5 ± 8.3 kg; 177.0 ± 5.6 cm; 24.7 ± 2.6 kg∙m-2). Participants were randomized into two groups: a percussion therapy group (PTG) and a control group (CG). They performed 4 sets at 70% of a one-repetition maximum before reaching a 30% velocity loss threshold with an inter-set recovery of 3 min. Results: The PTG performed a greater total number of repetitions compared to the CG (44.6 ± 4.8 vs. 39.5 ± 6.8; p = 0.047; ES = 0.867). No differences were observed for the different movement velocity variables and fatigue control (p > 0.05). Conclusions: Percussion therapy is an effective method to delay the loss of movement velocity in the bench press exercise.


Assuntos
Treinamento Resistido , Humanos , Masculino , Massagem , Força Muscular , Músculo Esquelético , Percussão , Levantamento de Peso
6.
Nutrients ; 13(6)2021 Jun 02.
Artigo em Inglês | MEDLINE | ID: mdl-34199420

RESUMO

Creatine supplementation in conjunction with resistance training (RT) augments gains in lean tissue mass and strength in aging adults; however, there is a large amount of heterogeneity between individual studies that may be related to creatine ingestion strategies. Therefore, the purpose of this review was to (1) perform updated meta-analyses comparing creatine vs. placebo (independent of dosage and frequency of ingestion) during a resistance training program on measures of lean tissue mass and strength, (2) perform meta-analyses examining the effects of different creatine dosing strategies (lower: ≤5 g/day and higher: >5 g/day), with and without a creatine-loading phase (≥20 g/day for 5-7 days), and (3) perform meta-analyses determining whether creatine supplementation only on resistance training days influences measures of lean tissue mass and strength. Overall, creatine (independent of dosing strategy) augments lean tissue mass and strength increase from RT vs. placebo. Subanalyses showed that creatine-loading followed by lower-dose creatine (≤5 g/day) increased chest press strength vs. placebo. Higher-dose creatine (>5 g/day), with and without a creatine-loading phase, produced significant gains in leg press strength vs. placebo. However, when studies involving a creatine-loading phase were excluded from the analyses, creatine had no greater effect on chest press or leg press strength vs. placebo. Finally, creatine supplementation only on resistance training days significantly increased measures of lean tissue mass and strength vs. placebo.


Assuntos
Envelhecimento/efeitos dos fármacos , Creatina/administração & dosagem , Ingestão de Alimentos/efeitos dos fármacos , Idoso , Suplementos Nutricionais , Alimentos Fortificados , Humanos , Força Muscular/efeitos dos fármacos , Músculo Esquelético/efeitos dos fármacos , Treinamento Resistido , Levantamento de Peso
7.
Artigo em Inglês | MEDLINE | ID: mdl-34067984

RESUMO

BACKGROUND: Recovery from training is vital as it ensures training and performance to continue at high intensities and longer durations to stimulate the body and cause further adaptations. OBJECTIVE: To evaluate different methods of post-workout recovery in Paralympic powerlifting athletes. METHODS: Twelve male athletes participated (25.4 ± 3.3 years; 70.3 ± 12.1 kg). The presence of muscle edema, pain threshold, plasma cytokines, and performance measurement were evaluated five times. The recovery methods used in this study were passive recovery (PR), dry needling (DN), and cold-water immersion (CWI). RESULTS: The data analysis showed that the maximal force decreased compared to the pretest value at 15 min and 2 h. The results also revealed that CWI and DN increased Interleukin 2 (IL-2) levels from 24 to 48 h more than that from 2 h to 24 h. After DN, muscle thickness did not increase significantly in any of the muscles, and after 2 h, muscle thickness decreased significantly again in the major pectoralis muscle. After CWI, pain pressure stabilized after 15 min and increased significantly again after 2 h for acromial pectoralis. CONCLUSION: The strength training sessions generate several changes in metabolism and different recovery methods contribute differently to maintain homeostasis in Paralympic powerlifting athletes.


Assuntos
Treinamento Resistido , Levantamento de Peso , Adaptação Fisiológica , Atletas , Temperatura Baixa , Humanos , Masculino , Músculo Esquelético , Fatores de Tempo , Água
9.
J Back Musculoskelet Rehabil ; 34(4): 689-696, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33896805

RESUMO

BACKGROUND: The multifidus muscle is located near the spine and controls the erection of the spine and stabilization during movements of the spine and extremities, and assists in all other spinal movements. Differences in paraspinal muscles between sides and levels, particularly in he multifidus, have been proposed as possible indicators of low back pain or spinal pathology. OBJECTIVE: This study aims to examine the cross-sectional area of the lumbar multifidus muscle at L4-L5 vertebral levels on ultrasound images of athletes in Olympic-style weightlifting, judo athletes and sedentary individuals. METHODS: This study included asymptomatic male athletes (athletes in Olympic-style weightlifting, n= 17, age: 19.24 ± 1.88, judo athletes, n= 17, age: 19.18 ± 1.23) and sedentary individuals (n= 17, age: 19.88 ± 1.31). The cross-sectional area of lumbar multifidus muscles was assessed bilaterally at the L4-L5 segments level in prone and using ultrasound imaging. RESULTS: Lumbar multifidus muscle cross-sectional areas of athletes in Olympic-style weightlifting and judo athletes were larger than those of sedentary individuals (p< 0.004). No asymmetric development was observed in cross-sectional areas of right-left lumbar multifidus muscle at L4-L5 levels of athletes in Olympic-style weightlifting and sedentary individuals (p> 0.008). The cross-sectional areas of the right and left lumbar multifidus muscle at L5 segment of individuals in judo athletes was found to be asymmetrical (p< 0.008). CONCLUSION: Our study shows that the cross-sectional areas of athletes in Olympic-style weightlifting and judo athletes are larger than that of sedentary individuals. The difference in the cross-sectional area of the lumbar multifidus muscle of athlete and sedentary groups might be said to result from hypertrophic effect of trainings of these athletes on the cross-sectional area of the lumbar multifidus muscle.


Assuntos
Atletas , Região Lombossacral/diagnóstico por imagem , Músculos Paraespinais/diagnóstico por imagem , Adolescente , Exercício Físico , Humanos , Dor Lombar/diagnóstico por imagem , Masculino , Artes Marciais , Ultrassonografia , Levantamento de Peso , Adulto Jovem
10.
Forensic Sci Int ; 322: 110771, 2021 May.
Artigo em Inglês | MEDLINE | ID: mdl-33838562

RESUMO

Substandard/counterfeit drugs are a growing global problem. According to the World Health Organisation, counterfeit medicines are medicines that are mislabelled deliberately and fraudulently regarding their identity and/or source. In high income countries, drugs seized are mainly represented by performance and image enhancing drugs (PIEDs). The aim of this study was to present the qualitative and quantitative results of toxicological analyses of pharmaceutical and dietary supplements seized from the black market among bodybuilders in France. All dietary supplements and pharmaceuticals seized from the black market and addressed to the laboratory for a qualitative and quantitative analysis between January 2016 and December 2019 were included in the study. A screening was carried out by gas chromatography-mass spectrometry and liquid chromatography-high resolution mass spectrometry. Identified compounds were quantified by liquid chromatography-tandem mass spectrometry. One hundred and ten products were seized and submitted to the laboratory for identification of active compounds and quantification: 75 pharmaceuticals and 35 dietary supplements. This included 39 oily and 3 aqueous solutions for intramuscular injection, 34 tablets, 13 capsules, 14 powders, 4 liquids and 3 lyophilizates. Among the pharmaceuticals, 25/75 (33%) were substandard (dosage not on the acceptable range defined for original products), 24/75 (32%) were counterfeit (qualitative formulation does not match the label) and 14/75 (19%) were original (qualitative formulation and levels of active ingredients fully matches the declared formulation. The analysis of the 12 remaining products revealed a correct qualitative content for 11/75 (15%), but quantitation could not be carried out because of the lack of reference standards at the time of the analysis. Fifty-four pharmaceuticals contained anabolic-androgenic steroids (AAS). Four out of 54 (7.4%) AAS were found as original, 8/54 (15%) could not be quantified (one with wrong active ingredient), corresponding to 43/54 (80%) AAS being non-original. In contrast, only 1/35 dietary supplement (3%) was adulterated, with a doping substance (1,3-dimethylbutylamine, DMBA). This work allows to show that France is not spared by the trafficking of PIEDs. The use of counterfeit drugs in mainstream population is an underestimated public health issue.


Assuntos
Dopagem Esportivo , Levantamento de Peso , Anabolizantes/análise , Cromatografia Líquida de Alta Pressão , Medicamentos Falsificados , Suplementos Nutricionais , Contaminação de Medicamentos , Cromatografia Gasosa-Espectrometria de Massas , Hormônio Liberador de Hormônio do Crescimento/análise , Humanos
11.
Res Q Exerc Sport ; 92(3): 500-513, 2021 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-32633646

RESUMO

Purpose: It has been suggested that the media influence beliefs regarding ideal body appearance and drive for muscularity whilst also offering recommendations for achieving this; most commonly heavy load free weight resistance training (RT). However, evidence for media effects are inconsistent in the literature. This study investigated this "lift big-get big" culture and effects of imagery on males' beliefs regarding RT. Method: An online survey was conducted with male participants (N = 110) randomized to different images (hyper-muscular/lean/control) and RT information ("lift big-get big"/"evidence based RT"/control). Results: Descriptive data suggested belief in necessity of heavy loads and free weights was pervasive. There was a small significant effect of condition for multivariate analysis of beliefs regarding RT. Univariate analyses showed significant effects of condition regarding the importance of free weights and heavy loads for strength, and free weights for hypertrophy. Small to moderate effects were found comparing "evidence-based RT" with a hyper-muscular physique to "lift big-get big" conditions with both hyper-muscular and lean physiques, the latter more likely to agree free weights and heavy loads are necessary for strength. A small effect was found comparing "lift big-get big" conditions with both hyper-muscular and lean physiques and the control condition, the former more likely to agree free weights are necessary for hypertrophy. Conclusions: Although hyper-muscular bodies alone did not influence RT beliefs, new information, i.e., "evidence-based RT" combined with a hyper-muscular physique had a small effect. The "lift big-get big" culture is perhaps pervasive enough that most conditions merely reinforced existing beliefs.


Assuntos
Masculinidade , Meios de Comunicação de Massa , Força Muscular/fisiologia , Treinamento Resistido , Levantamento de Peso/fisiologia , Levantamento de Peso/psicologia , Adolescente , Adulto , Humanos , Masculino , Pessoa de Meia-Idade , Inquéritos e Questionários , Adulto Jovem
12.
Nutrients ; 12(9)2020 Aug 19.
Artigo em Inglês | MEDLINE | ID: mdl-32824920

RESUMO

The aim of the present study was to analyze the effect of creatine (Cr) supplementation on peak torque (PT) and fatigue rate in Paralympic weightlifting athletes. Eight Paralympic powerlifting athletes participated in the study, with 25.40 ± 3.30 years and 70.30 ± 12.15 kg. The measurements of muscle strength, fatigue index (FI), peak torque (PT), force (kgf), force (N), rate of force development (RFD), and time to maximum isometric force (time) were determined by a Musclelab load cell. The study was performed in a single-blind manner, with subjects conducting the experiments first with placebo supplementation and then, following a 7-day washout period, beginning the same protocol with creatine supplementation for 7 days. This sequence was chosen because of the lengthy washout of creatine. Regarding the comparison between conditions, Cr supplementation did not show effects on the variables of muscle force, peak torque, RFD, and time to maximum isometric force (p > 0.05). However, when comparing the results of the moments with the use of Cr and placebo, a difference was observed for the FI after seven days (U3: 1.12; 95% CI: (0.03, 2.27); p = 0.02); therefore, the FI was higher for placebo. Creatine supplementation has a positive effect on the performance of Paralympic powerlifting athletes, reducing fatigue index, and keeping the force levels as well as PT.


Assuntos
Creatina/administração & dosagem , Suplementos Nutricionais , Fadiga Muscular/efeitos dos fármacos , Força Muscular/efeitos dos fármacos , Músculo Esquelético/fisiologia , Paratletas , Fenômenos Fisiológicos da Nutrição Esportiva/fisiologia , Levantamento de Peso/fisiologia , Adulto , Brasil , Creatina/farmacologia , Humanos , Contração Isométrica/efeitos dos fármacos , Masculino , Método Simples-Cego , Torque , Adulto Jovem
13.
Nutrients ; 12(8)2020 Aug 09.
Artigo em Inglês | MEDLINE | ID: mdl-32784847

RESUMO

This randomized trial compared pea protein, whey protein, and water-only supplementation on muscle damage, inflammation, delayed onset of muscle soreness (DOMS), and physical fitness test performance during a 5-day period after a 90-min eccentric exercise bout in non-athletic non-obese males (n = 92, ages 18-55 years). The two protein sources (0.9 g protein/kg divided into three doses/day) were administered under double blind procedures. The eccentric exercise protocol induced significant muscle damage and soreness, and reduced bench press and 30-s Wingate performance. Whey protein supplementation significantly attenuated post-exercise blood levels for biomarkers of muscle damage compared to water-only, with large effect sizes for creatine kinase and myoglobin during the fourth and fifth days of recovery (Cohen's d > 0.80); pea protein versus water supplementation had an intermediate non-significant effect (Cohen's d < 0.50); and no significant differences between whey and pea protein were found. Whey and pea protein compared to water supplementation had no significant effects on post-exercise DOMS and the fitness tests. In conclusion, high intake of whey protein for 5 days after intensive eccentric exercise mitigated the efflux of muscle damage biomarkers, with the intake of pea protein having an intermediate effect.


Assuntos
Suplementos Nutricionais , Músculo Esquelético/efeitos dos fármacos , Mialgia/prevenção & controle , Proteínas de Ervilha/farmacologia , Proteínas do Soro do Leite/farmacologia , Adolescente , Adulto , Biomarcadores/sangue , Proteína C-Reativa/efeitos dos fármacos , Creatina Quinase/sangue , Método Duplo-Cego , Teste de Esforço , Humanos , Masculino , Pessoa de Meia-Idade , Mioglobina/sangue , Aptidão Física/fisiologia , Levantamento de Peso/fisiologia , Adulto Jovem
14.
J Int Soc Sports Nutr ; 17(1): 45, 2020 08 24.
Artigo em Inglês | MEDLINE | ID: mdl-32831109

RESUMO

BACKGROUND: Energy drinks are often consumed by the general population, as well as by active individuals seeking to enhance exercise performance and augment training adaptations. However, limited information is available regarding the efficacy of these products. Thus, the purpose of this study was to determine the effects of a commercially available caffeine- and protein-containing energy drink on metabolism and muscular performance. METHODS: Sixteen resistance-trained males (n = 8; mean ± SD; age: 22.4 ± 4.9 years; body mass: 78.8 ± 14.0 kg; body fat: 15.3 ± 6.4%) and females (n = 8; age: 24.5 ± 4.8 years; body mass: 67.5 ± 11.9 kg; body fat: 26.6 ± 7.1%) participated in this randomized, double-blind, placebo-controlled, crossover study. Following a familiarization visit, participants completed two identical visits to the laboratory separated by 5-10 days, each of which consisted of indirect calorimetry energy expenditure (EE) assessments before and after consumption of the beverage (Bang® Keto Coffee; 130 kcal, 300 mg caffeine, 20 g protein) or placebo (30 kcal, 11 mg caffeine, 1 g protein) as well as after exercise testing. In addition, participants' subjective feelings of energy, fatigue, and focus as well as muscular performance (leg press one-repetition maximum and repetitions to fatigue, maximal isometric and isokinetic squat testing) were assessed. Multiple repeated measures ANOVAs with Tukey post-hoc tests were used to analyze data. Estimates of effect size were quantified via partial eta squared (ηP2) and Hedge's g. RESULTS: A significant interaction effect was identified for EE (p < 0.001, ηP2 = 0.52) but not respiratory exchange ratio (p = 0.17, ηP2 = 0.11). Following consumption of the beverage, EE was 0.18 [corrected] kcal·min- 1 greater than placebo at the post-beverage time point (p < 0.001) and 0.08 [corrected] kcal·min- 1 greater than placebo at the post-exercise time point (p = 0.011). However, no between-condition differences were detected for any subjective or muscular performance outcomes. CONCLUSIONS: The results of this study suggest that consumption of the energy drink had minimal effects on lower-body muscular performance and subjective factors in the context of a laboratory setting. However, the beverage was found to significantly increase energy expenditure compared to placebo immediately following ingestion as well as during the recovery period after an exercise bout, suggesting that active individuals may improve acute metabolic outcomes via consumption of a caffeine- and protein-containing energy drink. TRIAL REGISTRATION: This trial was prospectively registered at ClinicalTrials.gov (Identifier: NCT04180787 ; Registered 29 November 2019).


Assuntos
Café , Bebidas Energéticas , Metabolismo Energético/fisiologia , Exercício Físico/fisiologia , Músculo Esquelético/fisiologia , Treinamento Resistido , Adolescente , Adulto , Cafeína/farmacologia , Calorimetria Indireta , Estudos Cross-Over , Método Duplo-Cego , Metabolismo Energético/efeitos dos fármacos , Teste de Esforço/métodos , Feminino , Humanos , Perna (Membro)/fisiologia , Masculino , Músculo Esquelético/efeitos dos fármacos , Substâncias para Melhoria do Desempenho/farmacologia , Troca Gasosa Pulmonar/efeitos dos fármacos , Treinamento Resistido/métodos , Levantamento de Peso/fisiologia , Adulto Jovem
15.
Artigo em Inglês | MEDLINE | ID: mdl-32629826

RESUMO

The functional preference for the upper limb influences the occurrence of bilateral differences in other segments of the human body. The aim of the study is to assess the influence of the applied fighting technique and targeted physical effort on the occurrence of asymmetry in body musculature and isometric strength in bodybuilders and competitors of selected martial arts. Academic athletes practicing judo (J), jiu-jitsu (JJ), and bodybuilding (BB) were examined. The control group (C) consisted of students who do not practice any sports. The assessment of the body structure was conducted through segmental bioelectrical impedance analysis. Moreover, the study took into account the measurements of left- and right-hand grip strength. In judo, the uneven physical exertion of the right and left sides of the body further increases both directional and absolute asymmetry. Bilateral asymmetry of musculature in jiu-jitsu competitors and bodybuilders occurs to a lesser extent. The control group was characterized by cross-asymmetry. So as to avoid the risk of injury of sportsmen, it is important to consistently supervise and correct their body structure, which also includes the symmetrical participation of the active muscle mass in particular segments. The symmetrisation process should be individualized since each particular sportsman has their own side-to-side body morphology.


Assuntos
Força da Mão , Artes Marciais , Levantamento de Peso , Atletas , Mãos , Humanos , Esforço Físico
16.
Nutrients ; 12(8)2020 Jul 26.
Artigo em Inglês | MEDLINE | ID: mdl-32722588

RESUMO

Dietary nitrate (NO3-) supplementation has been evidenced to induce an ergogenic effect in endurance and sprint-type exercise, which may be underpinned by enhanced muscle contractility and perfusion, particularly in type II muscle fibers. However, limited data are available to evaluate the ergogenic potential of NO3- supplementation during other exercise modalities that mandate type II fiber recruitment, such as weightlifting exercise (i.e., resistance exercise). In this systematic review, we examine the existing evidence basis for NO3- supplementation to improve muscular power, velocity of contraction, and muscular endurance during weightlifting exercise in healthy adults. We also discuss the potential mechanistic bases for any positive effects of NO3- supplementation on resistance exercise performance. Dialnet, Directory of Open Access Journals, Medline, Pubmed, Scielo, Scopus and SPORT Discus databases were searched for articles using the keywords: nitrate or beetroot and supplement or nut*r or diet and strength or "resistance exercise" or "resistance training" or "muscular power". Four articles fulfilling the inclusion criteria were identified. Two of the four studies indicated that NO3- supplementation could increase aspects of upper body weightlifting exercise (i.e., bench press) performance (increases in mean power/velocity of contraction/number of repetitions to failure), whereas another study observed an increase in the number of repetitions to failure during lower limb weightlifting exercise (i.e., back squat). Although these preliminary observations are encouraging, further research is required for the ergogenic potential of NO3- supplementation on weightlifting exercise performance to be determined.


Assuntos
Desempenho Atlético/fisiologia , Suplementos Nutricionais , Nitratos/farmacologia , Substâncias para Melhoria do Desempenho/farmacologia , Levantamento de Peso/fisiologia , Adulto , Voluntários Saudáveis , Humanos , Masculino , Músculo Esquelético/efeitos dos fármacos , Resistência Física/efeitos dos fármacos , Treinamento Resistido
17.
Am J Emerg Med ; 38(11): 2487.e1-2487.e5, 2020 11.
Artigo em Inglês | MEDLINE | ID: mdl-32532617

RESUMO

Millions of people worldwide use nutritional and dietary supplements, such as vitamins and minerals. These and other performance-enhancing substances are also used by high school, college, and professional athletes, bodybuilders, and amateur sports enthusiasts. The constituents of these supplements and their metabolites may be harmful and not listed on the product label. We present a case report of a 32-year-old bodybuilder using myriad nutritional, performance-enhancing, and weight-loss supplements with life-threatening encephalopathy, hepatic failure, rhabdomyolysis, and copper toxicity mimicking Wilson's disease. Emergency physicians and nurses should be aware of these potential deleterious effects and inquire about supplement use by patients with unexplained multiorgan failure. Family, friends, or acquaintances should be asked to bring the actual products to the hospital for analysis.


Assuntos
Fármacos Antiobesidade/intoxicação , Encefalopatias/induzido quimicamente , Doença Hepática Induzida por Substâncias e Drogas/etiologia , Cobre/intoxicação , Suplementos Nutricionais/intoxicação , Falência Hepática Aguda/induzido quimicamente , Substâncias para Melhoria do Desempenho/intoxicação , Rabdomiólise/induzido quimicamente , Oligoelementos/intoxicação , Adulto , Creatina Quinase/metabolismo , Diagnóstico Diferencial , Degeneração Hepatolenticular/diagnóstico , Humanos , Falência Hepática Aguda/metabolismo , Testes de Função Hepática , Masculino , Rabdomiólise/metabolismo , Levantamento de Peso
18.
Res Sports Med ; 28(4): 469-483, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32482095

RESUMO

BACKGROUND:  In the elderly, low protein intake exacerbates the effects of sarcopenia and anabolic resistance.  Protein supplementation to maximise muscle protein synthesis, may be an effective intervention. Aim: To determine the effects of a low/high dose of protein, ingested immediately post-exercise, during resistance training in novice elderly males. Method: 24 elderly (70.5±5.1, years) males were recruited (body mass: 92.4±14.9 kg; fat free mass: 61.4±7.6 kg).  After exclusion criteria, 18 males participated. Participants continued their normal dietary intake and were allocated into two matched groups, then randomly assigned to either a 20 g or 40 g dose intervention. Following determination of 1 repetition maximum (1RM), participants completed 10 x 3d-1 wk resistance training and consumed protein supplements immediately following exercise. Results: Significant improvements in chest press (p = 0.014, ɳp2 0.34) shoulder press (p = 0.005, ɳp2 0.43) and leg extension strength (p = 0.014, ɳp2 0.34), were observed following the 40 g dose, resulting in performance improvements of 19.1, 21.1, and 16.1% respectively, compared to the 20 g dose. Conclusion:Findings suggest that ingesting 40 g of protein following resistance exercise, produces greater responses to training and may be an important nutritional strategy when prescribing resistance exercise in the elderly.


Assuntos
Adaptação Fisiológica , Suplementos Nutricionais , Força Muscular/fisiologia , Treinamento Resistido/métodos , Levantamento de Peso/fisiologia , Proteínas do Soro do Leite/administração & dosagem , Fatores Etários , Idoso , Idoso de 80 Anos ou mais , Distribuição da Gordura Corporal , Índice de Massa Corporal , Humanos , Masculino , Pessoa de Meia-Idade
19.
BMC Nephrol ; 21(1): 164, 2020 05 06.
Artigo em Inglês | MEDLINE | ID: mdl-32375656

RESUMO

BACKGROUND: The incidence of kidney diseases among bodybuilders is unknown. METHODS: Between January 2011 and December 2019, the Iraqi Kurdistan 15 to 39 year old male population averaged 1,100,000 with approximately 56,000 total participants and 25,000 regular participants (those training more than 1 year). Annual age specific incidence rates (ASIR) with (95% confidence intervals) per 100,000 bodybuilders were compared with the general age-matched male population. RESULTS: Fifteen male participants had kidney biopsies. Among regular participants, diagnoses were: focal segmental glomerulosclerosis (FSGS), 2; membranous glomerulonephritis (MGN), 2; post-infectious glomeruonephritis (PIGN), 1; tubulointerstitial nephritis (TIN), 1; and nephrocalcinosis, 2. Acute tubular necrosis (ATN) was diagnosed in 5 regular participants and 2 participants training less than 1 year. Among regular participants, anabolic steroid use was self-reported in 26% and veterinary grade vitamin D injections in 2.6%. ASIR for FSGS, MGN, PIGN, and TIN among regular participants was not statistically different than the general population. ASIR of FSGS adjusted for anabolic steroid use was 3.4 (- 1.3 to 8.1), a rate overlapping with FSGS in the general population at 2.0 (1.2 to 2.8). ATN presented as exertional muscle injury with myoglobinuria among new participants. Nevertheless, ASIR for ATN among total participants at 1.4 (0.4 to 2.4) was not significantly different than for the general population at 0.3 (0.1 to 0.5). Nephrocalcinosis was only diagnosed among bodybuilders at a 9-year cumulative rate of one per 314 vitamin D injectors. CONCLUSIONS: Kidney disease rates among bodybuilders were not significantly different than for the general population, except for nephrocalcinosis that was caused by injections of veterinary grade vitamin D compounds.


Assuntos
Nefropatias/epidemiologia , Nefropatias/patologia , Túbulos Renais/patologia , Congêneres da Testosterona/administração & dosagem , Vitamina D/administração & dosagem , Levantamento de Peso/estatística & dados numéricos , Doença Aguda , Adulto , Biópsia , Glomerulosclerose Segmentar e Focal/epidemiologia , Glomerulosclerose Segmentar e Focal/patologia , Humanos , Incidência , Iraque/epidemiologia , Nefropatias/diagnóstico , Masculino , Necrose/epidemiologia , Nefrite Intersticial/patologia , Nefrocalcinose/induzido quimicamente , Nefrocalcinose/epidemiologia , Nefrocalcinose/patologia , Vitamina D/efeitos adversos , Adulto Jovem
20.
J Appl Behav Anal ; 53(4): 2349-2359, 2020 09.
Artigo em Inglês | MEDLINE | ID: mdl-32378192

RESUMO

Auditory feedback has been successfully used to enhance performance in several sports such as golf and dance. The current study used auditory feedback procedures (i.e., a clicker) to improve the performance of 3 students performing a handstand. Handstands are part of a discipline called body weight training, that uses only the weight of an individual's own body to gain strength and body control. A multiple baseline design across four components was used to evaluate the effectiveness of auditory feedback. The results showed that auditory feedback was effective. The students and the trainer were highly satisfied with the auditory feedback procedure. Implications for future research are discussed.


Assuntos
Peso Corporal , Retroalimentação Sensorial , Treinamento Resistido , Estimulação Acústica , Adulto , Feminino , Humanos , Masculino , Levantamento de Peso
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