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1.
Hum Genomics ; 18(1): 47, 2024 May 17.
Artigo em Inglês | MEDLINE | ID: mdl-38760851

RESUMO

Association between genomic variants and athletic performance has seen a high degree of controversy, as there is often conflicting data as far as the association of genomic variants with endurance, speed and strength is concerned. Here, findings from a thorough meta-analysis from 4228 articles exploring the association of genomic variants with athletic performance in power and endurance sports are summarized, aiming to confirm or overrule the association of genetic variants with athletic performance of all types. From the 4228 articles, only 107 were eligible for further analysis, including 37 different genes. From these, there were 21 articles for the ACE gene, 29 articles for the ACTN3 gene and 8 articles for both the ACE and ACTN3 genes, including 54,382 subjects in total, from which 11,501 were endurance and power athletes and 42,881 control subjects. These data show that there is no statistically significant association between genomic variants and athletic performance either for endurance or power sports, underlying the fact that it is highly risky and even unethical to make such genetic testing services for athletic performance available to the general public. Overall, a strict regulatory monitoring should be exercised by health and other legislative authorities to protect the public from such services from an emerging discipline that still lacks the necessary scientific evidence and subsequent regulatory approval.


Assuntos
Actinina , Desempenho Atlético , Genômica , Resistência Física , Humanos , Resistência Física/genética , Actinina/genética , Peptidil Dipeptidase A/genética , Atletas , Esportes , Variação Genética/genética
2.
J Physiol ; 602(17): 4129-4156, 2024 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-39106346

RESUMO

Sex as a biological variable is an underappreciated aspect of biomedical research, with its importance emerging in more recent years. This review assesses the current understanding of sex differences in human physical performance. Males outperform females in many physical capacities because they are faster, stronger and more powerful, particularly after male puberty. This review highlights key sex differences in physiological and anatomical systems (generally conferred via sex steroids and puberty) that contribute to these sex differences in human physical performance. Specifically, we address the effects of the primary sex steroids that affect human physical development, discuss insight gained from an observational study of 'real-world data' and elite athletes, and highlight the key physiological mechanisms that contribute to sex differences in several aspects of physical performance. Physiological mechanisms discussed include those for the varying magnitude of the sex differences in performance involving: (1) absolute muscular strength and power; (2) fatigability of limb muscles as a measure of relative performance; and (3) maximal aerobic power and endurance. The profound sex-based differences in human performance involving strength, power, speed and endurance, and that are largely attributable to the direct and indirect effects of sex-steroid hormones, sex chromosomes and epigenetics, provide a scientific rationale and framework for policy decisions on sex-based categories in sports during puberty and adulthood. Finally, we highlight the sex bias and problem in human performance research of insufficient studies and information on females across many areas of biology and physiology, creating knowledge gaps and opportunities for high-impact studies.


Assuntos
Caracteres Sexuais , Humanos , Feminino , Masculino , Hormônios Esteroides Gonadais/metabolismo , Desempenho Físico Funcional , Desempenho Atlético/fisiologia
3.
Eur J Neurosci ; 60(5): 5086-5110, 2024 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-39120435

RESUMO

This systematic review and meta-analysis assesses independently the acute effects of anodal and cathodal motor cortex transcranial direct current stimulation (tDCS) on athletic performance in healthy adults. Besides, it evaluates the unique and conjoint effects of potential moderators (i.e., stimulation parameters, exercise type, subjects' training status and risk of bias). Online database search was performed from inception until March 18th 2024 (PROSPERO: CRD42023355461). Forty-three controlled trials were included in the systematic review, 40 in the anodal tDCS meta-analysis (68 effects), and 9 (11 effects) in the cathodal tDCS meta-analysis. Performance enhancement between pre- and post-stimulation was the main outcome measure considered. The anodal tDCS effects on physical performance were small to moderate (g = .29, 95%CI [.18, .40], PI = -.64 to 1.23, I2 = 64.0%). Exercise type, training status and use of commercial tDCS were significant moderators of the results. The cathodal tDCS effects were null (g = .04, 95%CI [-.05, .12], PI = -.14 to .23, I2 = 0%), with a small to moderate heterogeneity entirely due to sampling error, thus impairing further moderator analysis. These findings hold significant implications for the field of brain stimulation and physical performance, as they not only demonstrate a small to moderate effect of acute tDCS but also identify specific categories of individuals, devices and activities that are more susceptible to improvements. By addressing the multidimensional factors influencing the mechanisms of tDCS, we also provide suggestions for future research.


Assuntos
Desempenho Atlético , Córtex Motor , Estimulação Transcraniana por Corrente Contínua , Estimulação Transcraniana por Corrente Contínua/métodos , Humanos , Córtex Motor/fisiologia , Desempenho Atlético/fisiologia , Adulto
4.
Artigo em Inglês | MEDLINE | ID: mdl-39377784

RESUMO

Psychotropic drugs are vital in psychiatry, aiding in the management of mental health disorders. Their use requires an understanding of their pharmacological properties, therapeutic applications, and potential side effects. Ongoing research aims to improve their efficacy and safety. Biomarkers play a crucial role in understanding and predicting memory decline in psychotropic drug users. A comprehensive understanding of biomarkers, including neuroimaging, biochemical, genetic, and cognitive assessments, is essential for developing targeted interventions and preventive strategies. In this narrative review, we performed a comprehensive search on PubMed and Google using review-specific terms. Clinicians should use a multifaceted approach, including neurotransmitter analysis, neurotrophic factors, miRNA profiling, and cognitive tasks for early intervention and personalized treatment. Anxiolytics' mechanisms involve various neurotransmitter systems and emerging targets. Research on biomarkers for memory decline in anxiolytic users can lead to early detection and intervention, enhancing clinical practices and aligning with precision medicine. Mood stabilizer users can benefit from early detection of memory decline through RNA, neurophysiological, and inflammatory biomarkers, promoting timely interventions. Performance-enhancing drugs may boost athletic performance in the short term, but their long-term health risks and ethical issues make their use problematic. Long-term use of psychotropic performance enhancers in athletes shows changes in biomarkers of cognitive decline, necessitating ongoing monitoring and intervention strategies. Understanding these genetic influences on memory decline helps pave the way for personalized approaches to prevent or mitigate cognitive deterioration, emphasizing the importance of genetic screening and early interventions based on an individual's genetic profile. Future research should focus on refining these biomarkers and protective measures against cognitive deterioration. Overall, a comprehensive understanding of biomarkers in psychotropic drug users is essential for developing targeted interventions and preventive strategies.

5.
Br J Nutr ; 131(9): 1579-1590, 2024 May 14.
Artigo em Inglês | MEDLINE | ID: mdl-38299306

RESUMO

We aim to understand the effects of hydration changes on athletes' neuromuscular performance, on body water compartments, fat-free mass hydration and hydration biomarkers and to test the effects of the intervention on the response of acute dehydration in the hydration indexes. The H2OAthletes study (clinicaltrials.gov ID: NCT05380089) is a randomised controlled trial in thirty-eight national/international athletes of both sexes with low total water intake (WI) (i.e. < 35·0 ml/kg/d). In the intervention, participants will be randomly assigned to the control (CG, n 19) or experimental group (EG, n 19). During the 4-day intervention, WI will be maintained in the CG and increased in the EG (i.e. > 45·0 ml/kg/d). Exercise-induced dehydration protocols with thermal stress will be performed before and after the intervention. Neuromuscular performance (knee extension/flexion with electromyography and handgrip), hydration indexes (serum, urine and saliva osmolality), body water compartments and water flux (dilution techniques, body composition (four-compartment model) and biochemical parameters (vasopressin and Na) will be evaluated. This trial will provide novel evidence about the effects of hydration changes on neuromuscular function and hydration status in athletes with low WI, providing useful information for athletes and sports-related professionals aiming to improve athletic performance.


Assuntos
Atletas , Água Corporal , Desidratação , Adulto , Feminino , Humanos , Masculino , Adulto Jovem , Desempenho Atlético/fisiologia , Composição Corporal , Ingestão de Líquidos/fisiologia , Eletromiografia , Exercício Físico/fisiologia , Força da Mão/fisiologia , Estado de Hidratação do Organismo , Equilíbrio Hidroeletrolítico/fisiologia , Ensaios Clínicos Controlados Aleatórios como Assunto
6.
Mol Biol Rep ; 51(1): 841, 2024 Jul 23.
Artigo em Inglês | MEDLINE | ID: mdl-39042267

RESUMO

BACKGROUND: This study aimed to achieve a dual objective: to compare the frequencies of CYP1A2 rs762551 genotypes between team sport athletes and a control group, and to determine the association between the rs762551 polymorphism and changes in physical performance after a six-week training program among elite basketball players. METHODS: The study encompassed an analysis of 504 individuals, comprising 320 athletes and 184 controls. For the Turkish cohort, DNA was isolated using the buccal swab method, and genotyping was conducted using the KASP technique. Performance assessments included the Yo-Yo IR2 and 30 m sprint tests. For Russian participants, DNA samples were extracted from peripheral blood, a commercial kit was used for DNA extraction, and genotyping of the rs762551 polymorphism was conducted using DNA microarray. RESULT: Notably, a statistically significant linear decline in the prevalence of the CC genotype was observed with ascending levels of athletic achievement within team sports (sub-elite: 18.0%, elite: 8.2%, highly elite: 0%; p = 0.001). Additionally, the CA genotype was the most prevalent genotype in the highly elite group compared to controls (80.0% vs. 45.1%, p = 0.048). Furthermore, statistically significant improvements in Yo-Yo IR2 performance were noted exclusively among basketball players harboring the CA genotype (p = 0.048). CONCLUSIONS: The study's findings indicate that the rs762551 CC genotype is a disadvantage in elite team sports, whereas the CA genotype provides an advantage in basketball performance.


Assuntos
Atletas , Desempenho Atlético , Cafeína , Citocromo P-450 CYP1A2 , Genótipo , Polimorfismo de Nucleotídeo Único , Humanos , Masculino , Citocromo P-450 CYP1A2/genética , Citocromo P-450 CYP1A2/metabolismo , Desempenho Atlético/fisiologia , Cafeína/metabolismo , Polimorfismo de Nucleotídeo Único/genética , Adulto Jovem , Feminino , Adulto , Esportes de Equipe , Basquetebol , Adaptação Fisiológica/genética , Turquia
7.
Scand J Med Sci Sports ; 34(9): e14717, 2024 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-39189630

RESUMO

This study aimed to analyze the chronic effect of high cognitive effort immediately before resistance exercise sessions on neuromuscular performance in untrained male adults. We used a mixed experimental design, with the group as between-participants factor and time as within-participants factor. Thirty-four participants were randomly assigned to two parallel groups: high cognitive effort (n = 17) and control (n = 17). Subjects in the control group were seated for 30 min before the resistance exercise sessions, while the high cognitive effort group completed incongruent trials of the Stroop task until subjective mental fatigue was present immediately before resistance exercise sessions. Participants attended 45 sessions over 15 weeks, consisting of three familiarizations, three baseline evaluations, 36 velocity-based training sessions, and three postexperiment evaluation sessions. Rate of force development (RFD) during the isometric mid-thigh pull, half back-squat 1-RM, and countermovement jump (CMJ) were measured before and after the 12-week intervention. A significant group × time interaction effect was found for the average RFD at 0-250 ms (p < 0.05), with greater improvements for the control group than for the high cognitive effort group. There was no group × time interaction for half back-squat 1-RM (p > 0.05). Also, there was no group × time interaction for CMJ (p > 0.05). In conclusion, repeated high cognitive effort immediately prior to resistance exercise sessions is a phenomenon that can induce greater early velocity loss and, consequently, impairs the improvements in RFD. However, this did not inhibit the increased performance for explosive strength and CMJ in male untrained adults. High cognitive effort before resistance exercise sessions should be avoided.


Assuntos
Cognição , Força Muscular , Treinamento Resistido , Humanos , Masculino , Treinamento Resistido/métodos , Força Muscular/fisiologia , Adulto Jovem , Cognição/fisiologia , Adulto , Teste de Stroop , Contração Isométrica/fisiologia , Músculo Esquelético/fisiologia , Fadiga Mental/prevenção & controle
8.
Eur J Appl Physiol ; 124(8): 2439-2450, 2024 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-38548939

RESUMO

PURPOSE: To evaluate the effects of repeated use of cold-water immersion (CWI) during a training week on performance and perceptive outcomes in competitive adolescent swimmers. METHODS: This randomized-crossover study included 20 athletes, who received each intervention [CWI (14 ± 1 °C), thermoneutral water immersion (TWI) (27 ± 1 °C) as placebo, and passive recovery (PAS)] three times a week between the land-based resistance training and swim training. The interventions were performed in a randomized order with a 1-week wash-out period. We tested athletes before and after each intervention week regarding swim (100 m freestyle sprints) and functional performance (flexibility, upper and lower body power, and shoulder proprioception). We monitored athlete's perceptions (well-being, heaviness, tiredness, discomfort and pain) during testing sessions using a 5-item questionnaire. Athlete preferences regarding the interventions were assessed at the end of the study. We used generalized linear mixed models and generalized estimating equations for continuous and categorical variables, respectively (intervention x time). RESULTS: We found a time effect for swim performance (p = .01) in which, regardless the intervention, all athletes improved sprint time at post-intervention compared to baseline. There was an intervention effect for pain (p = .04) and tiredness (p = .04), but with no significant post-hoc comparisons. We found no significant effects for other outcomes. All athletes reported a preference for CWI or TWI in relation to PAS. CONCLUSION: The repeated use of CWI throughout a training week did not impact functional or swim performance outcomes of competitive adolescent swimmers. Perceptive outcomes were also similar across interventions; however, athletes indicated a preference for both CWI and TWI.


Assuntos
Desempenho Atlético , Temperatura Baixa , Imersão , Natação , Humanos , Natação/fisiologia , Adolescente , Masculino , Desempenho Atlético/fisiologia , Feminino , Água , Estudos Cross-Over , Atletas
9.
Br J Sports Med ; 58(3): 136-143, 2024 Feb 07.
Artigo em Inglês | MEDLINE | ID: mdl-37923379

RESUMO

OBJECTIVE: To systematically review, summarise and appraise findings of published systematic reviews, with/without meta-analyses, examining associations between Ramadan fasting observance (RO), health-related indices and exercise test performances in athletes and physically active individuals. DESIGN: Overview of systematic reviews with assessment of reviews' methodological quality. DATA SOURCES: PubMed, Web of Science, Scopus, Cochrane Database of Systematic Reviews, SPORTDiscus, ProQuest, PsycINFO and SciELO. ELIGIBILITY CRITERIA FOR SELECTING STUDIES: Systematic reviews with/without meta-analyses examining associations of RO with health-related indices and exercise performances in athletes and physically active individuals. RESULTS: Fourteen systematic reviews (seven with meta-analyses) of observational studies, with low-to-critically-low methodological quality, were included. Two reviews found associations between RO and decreased sleep duration in athletes and physically active individuals. One review suggested athletes may experience more pronounced reductions in sleep duration than physically active individuals. One review found associations between RO and impaired sleep quality in athletes and physically active individuals. RO was associated with decreased energy, carbohydrate and water intake in adult-aged athletes, but not adolescents. One review suggests RO was associated with athletes' increased feelings of fatigue and decreased vigour. No association was found between RO and athletes' lean mass or haematological indices. RO was unfavourably associated with changes in athletes' performance during high-intensity exercise testing. CONCLUSION: Continuance of training during RO could be associated with athletes' mood state disturbances, decreased sleep duration and performance decline during high-intensity exercise testing, while preserving lean mass. However, careful interpretation is necessary due to the low-to-critically-low methodological quality of the included reviews.


Assuntos
Desempenho Atlético , Teste de Esforço , Humanos , Idoso , Jejum Intermitente , Revisões Sistemáticas como Assunto , Exercício Físico , Atletas
10.
Br J Sports Med ; 58(6): 299-312, 2024 Mar 13.
Artigo em Inglês | MEDLINE | ID: mdl-38148108

RESUMO

Female athletes have identified a lack of guidance as a barrier to successfully returning to running postpartum, and existing guidelines are vague. Our aim was to define the current practice of determining postpartum run-readiness through a consensus survey of international clinicians and exercise professionals in postpartum exercise to assist clinicians and inform sport policy changes.A three-round Delphi approach was used to gain international consensus from clinicians and exercise professionals on run-readiness postpartum. Professionals who work with postpartum runners participated in an online survey to answer open-ended questions about the following postpartum return-to-running topics: definitions (runner and postpartum), key biopsychosocial milestones that runners need to meet, recommended screening, timeline to initiate running, support items, education topics and factors that contribute to advising against running. Consensus was defined as ≥75% participant agreement.One hundred and eighteen professionals participated in round I, 107 participated in round II (response rate 90.6%) and 95 participated in round III (response rate 80.5%). Responses indicated that, following a minimum 3-week period of rest and recovery, an individualised timeline and gradual return to running progression can be considered. Screening for medical and psychological concerns, current physical capacity, and prior training history is recommended prior to a return to running.This study proposes recommendations for the initial guidance on return-to-running postpartum, framed in the context of current research and consensus from professionals. Future research is needed to strengthen and validate specific recommendations and develop guidelines for best practice when returning-to-running after childbirth.


Assuntos
Parto Obstétrico , Corrida , Humanos , Feminino , Gravidez , Técnica Delphi , Exercício Físico , Período Pós-Parto
11.
Br J Sports Med ; 58(17): 1021-1028, 2024 Sep 04.
Artigo em Inglês | MEDLINE | ID: mdl-39179362

RESUMO

OBJECTIVE: The objective of this study is to characterise the key factors that influence positive engagement and desirable developmental outcomes in sport among elite youth athletes by summarising the methods, groups and pertinent topical areas examined in the extant published research. DESIGN: Scoping review. DATA SOURCES: We searched the databases SPORTDiscus, APA PsycINFO, Web of Science and Sports Medicine & Education Index for peer-reviewed, published in English articles that considered the factors influencing positive developmental outcomes for athletes under 18 years competing at a national and/or international level. RESULTS: The search returned 549 articles, of which 43 met the inclusion criteria. 16 studies used a qualitative approach, 14 collected quantitative data, 2 adopted mixed methods and 11 were reviews. Seven articles involved athletes competing in absolute skill contexts (ie, against the best athletes of any age) while the majority involved athletes competing in relative skill contexts (ie, against the best in a specific age or developmental group). The studies described the characteristics of the athletes, as well as their training, relationships with others, social and physical environments, and/or their overall developmental pathways. CONCLUSION: Existing research on positive engagement in elite youth sport aligned with and mapped onto established models of positive development in youth sport more generally. Our findings further support that, while certain youth athletes may demonstrate extraordinary performance capabilities, they are still children who benefit from positive engagement prompted and reinforced by developmentally appropriate and supportive activities, relationships and environments.


Assuntos
Desempenho Atlético , Esportes Juvenis , Humanos , Criança , Adolescente , Desempenho Atlético/fisiologia , Atletas/psicologia
12.
Br J Sports Med ; 58(19): 1107-1114, 2024 Oct 17.
Artigo em Inglês | MEDLINE | ID: mdl-38981661

RESUMO

OBJECTIVES: To co-construct a sports medicine and exercise science research and translational agenda with Team USA elite female athletes serving as the experts on their health, performance and well-being. METHODS: 40 Team USA female athletes across sports disciplines participated in an online, anonymous, modified Delphi survey by ranking topics on a Likert scale (1='strongly disagree' and 5='strongly agree') and providing qualitative justification regarding whether they believed having more information and research on each topic would support their athletic performance, health and well-being. After each Delphi round, quantitative rankings of topics and qualitative justifications were analysed, informing revisions to the list of topics for review in the subsequent round. Researchers provided athletes with a detailed report of findings and revisions following each round. RESULTS: The final list contained 14 ranked topics. The top five were menstrual cycle symptoms (4.58±0.74), recovery (4.58±0.59), birth control (4.55±0.89), mental health (4.50±0.55) and fueling and the menstrual cycle (4.43±0.74). New topics originating from athletes included recovery, menstrual cycle symptoms, fueling and the menstrual cycle, mental health and sports performance, team dynamics, and institutionalised sexism. CONCLUSION: This is the first study to co-construct a research and translational agenda with Team USA elite female athletes. The list of sports science research topics developed by focusing on elite female athletes' voices lays the foundation for future research and provides valuable insight into the specific needs of female athletes.


Assuntos
Atletas , Desempenho Atlético , Técnica Delphi , Saúde Mental , Medicina Esportiva , Humanos , Feminino , Desempenho Atlético/fisiologia , Estados Unidos , Ciclo Menstrual/fisiologia , Adulto , Sexismo , Adulto Jovem
13.
J Sports Sci ; 42(7): 638-645, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38762890

RESUMO

This study examined the effects of an 8-week horizontal speed deceleration training (HSDT) programme in combination with regular handball-specific training as compared with handball-specific training only in measures of physical fitness in male youth handball players. Thirty-nine players were randomly assigned to either an HSDT group (n = 18; 15.55 ± 0.24 years) or an active-control group (CG; n = 21; 14.59 ± 0.23 years). The results showed significant and large between-group differences at post-test in countermovement jump, change-of-direction speed, and repeated sprint ability (RSA) (all p < 0.01; d = 2.04 and 1.37, 1.39, 1.53, and 1.53 for the CMJ, 505 CoD, RSAbest, RSAaverage, and RSAtotal performances, respectively). The post-hoc-analysis demonstrated significant and large improvements in all measures of physical fitness in the HSDT group (∆2.49% to 16,25%; d = 1.01 to 1,70; all p < 0,01). The CG, however, failed to reach any significant difference in all measures of physical fitness ((∆0.31% to 1.98%; d = 0.15 to 0.22; p = 0.379; p > 0.05). To summarise, an 8-week in-season HSDT programme alongside regular handball-specific training yielded positive effects on various performance measures including jumping ability, CoD speed, and RSA, when compared to handball-specific training alone. These results highlight the potential benefits of integrating HSDT into the training regimen of youth handball athletes during the competitive season.


Assuntos
Desempenho Atlético , Condicionamento Físico Humano , Aptidão Física , Humanos , Masculino , Adolescente , Aptidão Física/fisiologia , Desempenho Atlético/fisiologia , Condicionamento Físico Humano/métodos , Desaceleração , Esportes/fisiologia , Corrida/fisiologia
14.
J Sports Sci ; 42(1): 46-60, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-38433623

RESUMO

This systematic review investigates influences of mobility training in sporting populations on performance outcomes. The search strategy involved Embase, MEDLINE Complete, Sports Discus and manual search from inception to March 2022. Mobility training studies with a minimum three-week, or 10-session duration in healthy sporting populations of any age were included. Twenty-two studies comprising predominantly young adult or junior athletes were analysed from 319 retrieved articles. Performance outcomes were strength, speed, change of direction, jumping, balance, and sport-specific skills. Fifteen studies randomized participants with only four indicating systematic allocation concealment and blinding of outcomes assessors in only one study. In 20 of 22 studies mobility training was of some benefit or helped to maintain sports performance to a larger degree than control conditions. Control conditions, which were generally no activity conditions, were primarily non-significant. The majority of evidence suggests that a range of mobility training methods may improve key sports performance variables or are unlikely to impair performance over time. Therefore, coaches can consider the potential benefits of including comprehensive mobility programmes with minimal risk of impairing performance. Higher-quality studies in homogenous populations are necessary to confirm performance changes.


Assuntos
Desempenho Atlético , Condicionamento Físico Humano , Humanos , Desempenho Atlético/fisiologia , Condicionamento Físico Humano/métodos , Condicionamento Físico Humano/fisiologia , Força Muscular/fisiologia , Adaptação Fisiológica , Equilíbrio Postural/fisiologia , Destreza Motora/fisiologia
15.
Int J Sport Nutr Exerc Metab ; 34(6): 397-412, 2024 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-39032921

RESUMO

Beta-alanine is a nonessential amino acid that is commonly used to improve exercise performance. It could influence the buffering of hydrogen ions produced during intense exercise and delay fatigue, providing a substrate for increased synthesis of intramuscular carnosine. This systematic review evaluates the effects of beta-alanine supplementation on maximal intensity exercise in trained, young, male individuals. Six databases were searched on August 10, 2023, to identify randomized, double-blinded, placebo-controlled trials investigating the effect of chronic beta-alanine supplementation in trained male individuals with an age range of 18-40 years. Studies evaluating exercise performance through maximal or supramaximal intensity efforts falling within the 0.5-10 min duration were included. A total of 18 individual studies were analyzed, employing 18 exercise test protocols and 15 outcome measures in 331 participants. A significant (p = .01) result was observed with an overall effect size of 0.39 (95% confidence interval [CI] [0.09, 0.69]), in favor of beta-alanine supplementation versus placebo. Results indicate significant effects at 4 weeks of supplementation, effect size 0.34 (95% CI [0.02, 0.67], p = .04); 4-10 min of maximal effort, effect size 0.55 (95% CI [0.07, 1.04], p = .03); and a high beta-alanine dosage of 5.6-6.4 g per day, effect size 0.35 (95% CI [0.09, 0.62], p = .009). The results provide insights into which exercise modality will benefit the most, and which dosage protocols and durations stand to provide the greatest ergogenic effects. This may be used to inform further research, and professional or recreational training design, and optimization of supplementation strategies.


Assuntos
Suplementos Nutricionais , beta-Alanina , Adolescente , Adulto , Humanos , Masculino , Adulto Jovem , Desempenho Atlético/fisiologia , beta-Alanina/administração & dosagem , beta-Alanina/farmacologia , Carnosina/administração & dosagem , Exercício Físico/fisiologia , Substâncias para Melhoria do Desempenho/administração & dosagem , Substâncias para Melhoria do Desempenho/farmacologia , Ensaios Clínicos Controlados Aleatórios como Assunto , Fenômenos Fisiológicos da Nutrição Esportiva
16.
Sensors (Basel) ; 24(11)2024 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-38894359

RESUMO

This study aimed to determine the absolute and relative reliability of concentric and eccentric flexion, extension, horizontal abduction, and adduction movements of the shoulder using a functional electromechanical dynamometer (FEMD). Forty-three active male university students (23.51 ± 4.72 years) were examined for concentric and eccentric strength of shoulder flexion, extension, horizontal abduction, and horizontal adduction with an isokinetic test at 0.80 m·s-1. Relative reliability was determined by intraclass correlation coefficients (ICCs) with 95% confidence intervals. Absolute reliability was quantified by the standard error of measurement (SEM) and coefficient of variation (CV). Reliability was very high to extremely high for all movements on concentric and eccentric strength measurements (ICC: 0.76-0.94, SEM: 0.63-6.57%, CV: 9.40-19.63%). The results of this study provide compelling evidence for the absolute and relative reliability of concentric and eccentric flexion, extension, horizontal abduction, and horizontal adduction shoulder isokinetic strength tests in asymptomatic adults. The mean concentric force was the most reliable strength value for all tests.


Assuntos
Força Muscular , Ombro , Humanos , Masculino , Adulto , Força Muscular/fisiologia , Adulto Jovem , Ombro/fisiologia , Reprodutibilidade dos Testes , Amplitude de Movimento Articular/fisiologia , Dinamômetro de Força Muscular , Articulação do Ombro/fisiologia , Fenômenos Biomecânicos/fisiologia , Músculo Esquelético/fisiologia
17.
Sensors (Basel) ; 24(18)2024 Sep 13.
Artigo em Inglês | MEDLINE | ID: mdl-39338688

RESUMO

Objective: This study designed experiments to explore the effects of ischemic preconditioning (IPC) intervention with different cycling periods on the upper limb strength performance of college male bodybuilding athletes. Methods: Ten bodybuilding athletes were recruited for a randomized, double-blind, crossover experimental study. All subjects first underwent pre-tests with two sets of exhaustive bench presses at 60% of their one-repetition maximum (1RM) to assess upper limb strength performance. They then experienced three different IPC intervention modes (T1: 1 × 5 min, T2: 2 × 5 min, T3: 3 × 5 min), as well as a non-IPC intervention mode (CON), followed by a retest of the bench press. An Enode pro device was used to record the barbell's velocity during the bench press movement (peak velocity (PV), mean velocity (MV)); power (peak power (PP), mean power (MP)); and time under tension (TUT) to evaluate upper limb strength performance. Results: PV values: T1 showed significant increases compared to pre-tests in the first (p = 0.02) and second (p = 0.024) tests, and were significantly greater than the CON (p = 0.032); T2 showed a significant increase in PV in the first test (p = 0.035), with no significant differences in other groups. MV values: T1 showed a significant increase in MV in the first test compared to the pre-test (p = 0.045), with no significant differences in other groups. PP values: T1 showed a highly significant increase in PP in the first test compared to the pre-test (p = 0.001), and was significantly higher than the CON (p = 0.025). MP values: T1 showed highly significant increases in MP in both the first (p = 0.004) and second (p = 0.003) tests compared to the pre-test; T2 showed a highly significant increase in MP in the first test (p = 0.039) and a significant increase in the second test (p = 0.039). T1's MP values were significantly higher than the CON in both tests; T2's MP values were significantly higher than the CON in the first (p = 0.005) and second (p = 0.024) tests. TUT values: T1 showed highly significant increases in TUT in the first (p < 0.001) and second (p = 0.002) tests compared to the pre-test, and were significantly higher than the CON. Conclusions: (1) Single-cycle and double-cycle IPC interventions both significantly enhance upper limb strength performance, significantly improving the speed and power in exhaustive bench press tests, with the single-cycle IPC intervention being more effective than the double-cycle IPC intervention. (2) The triple-cycle IPC intervention does not improve the upper limb strength performance of bodybuilding athletes in exhaustive bench presses.


Assuntos
Atletas , Precondicionamento Isquêmico , Força Muscular , Extremidade Superior , Humanos , Masculino , Extremidade Superior/fisiologia , Força Muscular/fisiologia , Precondicionamento Isquêmico/métodos , Adulto Jovem , Estudos Cross-Over , Método Duplo-Cego , Adulto , Levantamento de Peso/fisiologia
18.
Eur J Contracept Reprod Health Care ; 29(1): 8-14, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-38108091

RESUMO

PURPOSE: Oral contraceptives (OCs) are commonly used by female athletes raising concerns regarding the possible adverse effects of OCs on physical performance, musculoskeletal injuries, and bone density. We aimed to review all current studies on the physiological effects of OCs in physically active women. MATERIALS AND METHODS: A review of literature in electronic search in PubMed and Google Scholar databases from December 2002 to December 2022 using relevant keywords. The reference lists of the articles found eligible were also reviewed. RESULTS: Out of 344 articles in the initial database, 54 clinical studies were eligible for inclusion in our literature review. OCs are used by about two-thirds of female athletes. Current research suggests that OCs' effects on endurance performance and muscle strength are mostly reassuring. OCs do not seem to have a major negative impact on bone health or sports injuries. In fact, new data suggests that they may even significantly reduce the risk of anterior cruciate ligament (ACL) injury. CONCLUSIONS: OCs can be safely used by young female athletes, who may also benefit from better menstrual cycle control. OCs offer newly realised protection from ACL injuries. The use of OCs must be carefully individualised according to their preferences, expectations, and experience.


Hormonal contraception can be safely prescribed to active women. The International Olympic Committee advocates a new and wider definition for the 'athlete triad', where low energy availability presents a special challenge for these athletes. New data suggests that the use of oral contraceptives may protect against ACL injury.


Assuntos
Lesões do Ligamento Cruzado Anterior , Traumatismos em Atletas , Humanos , Feminino , Contracepção Hormonal , Anticoncepcionais Orais , Ciclo Menstrual , Atletas , Traumatismos em Atletas/prevenção & controle , Lesões do Ligamento Cruzado Anterior/prevenção & controle
19.
J Sport Rehabil ; 33(1): 53-62, 2024 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-37917982

RESUMO

CONTEXT: Current devices to assess strength performance in handball may not be sufficiently sports-specific and reliable methods. Functional electromechanical dynamometry is a new technology that allows the development of accurate strength tests in athletes. PURPOSE: To determine the absolute and relative reliability and to compare the reliability of the right and left side, and mean and peak force of 3 specific strength tests in handball players with a functional electromechanical dynamometer: unilateral pullover, standing lift, and step forward. METHODS: Fourteen male handball players of the first Spanish division (28.79 [4.81] y; 10.38 [4.63] y of professional experience) performed a repeated-measurement design. Three testing sessions were performed (one per week). The first measurement consisted of 4 isometric tests (right and left unilateral pullover, and right and left standing lift) to obtain isometric peak force, and in the second and third sessions, 6 incremental tests until failure (right and left unilateral pullover, and right and left standing lift, right and left step forward) were performed. RESULTS: The tests provided high reliability or acceptable reliability for mean and peak strength of unilateral pullover, standing lift and step forward (intraclass correlation coefficient = .83-.97; coefficient of variation = 3.90-11.57). Effect side was negligible in any of the parameters, except for a small effect side in the left peak force for unilateral pullover and a small effect side on the left side for a step forward. Significant differences in reliability (coefficient of variation ratio > 1.15) were found between the right and left sides and peak and mean force in all exercises except peak force in unilateral pullover and step forward. CONCLUSION: These results confirm that the tests could be applied to assess physical performance in handball at the same time as regular gym training. Moreover, this is an excellent opportunity to individualize the player's weekly load.


Assuntos
Força Muscular , Esportes , Humanos , Masculino , Reprodutibilidade dos Testes , Atletas , Exercício Físico
20.
J Sport Rehabil ; 33(1): 33-39, 2024 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-37875255

RESUMO

CONTEXT: The aim of this prospective cohort study was to identify whether Y-Balance Test (YBT) performance and asymmetry are associated with lower limb injury in elite adult football athletes. DESIGN: A prospective cohort study. METHODS: Preseason YBT measures were obtained from 121 male footballers participating in National League One across the 2021-2022 season. Lower limb injuries were tracked across the season to determine the relationship between YBT variables and injury incidence using logistic regression analysis. The statistical significance level was .05. RESULTS: The average YBT score was 111.0 (5.8) cm on the left limb and 112.0 (5.5) cm on the right limb, with an average asymmetry of 2.3 (1.4) cm. Athletes with lower YBT scores on both the left (odds ratio = 2.9; 95% confidence interval, 1.7 to 4.8: P ≤ .001) and right (odds ratio = 2.3; 95% confidence interval, 1.6 to 3.2: P ≤ .001) limbs were at a greater risk of injury. Similarly, athletes with greater amounts of asymmetry were also more likely to get injured (odds ratio = 2.1; 95% confidence interval, 1.3 to 3.3: P = .002). CONCLUSIONS: Results indicate that lower and asymmetrical YBT scores have a significant relationship with future lower limb injuries in professional male footballers. The YBT offers a simple, reliable, and effective screening tool that can be used by practitioners in football to help identify players at a greater risk of injury before the season commences.


Assuntos
Traumatismos em Atletas , Futebol Americano , Adulto , Humanos , Masculino , Traumatismos em Atletas/diagnóstico , Traumatismos em Atletas/prevenção & controle , Estudos Prospectivos , Atletas , Futebol Americano/lesões , Extremidade Inferior/lesões
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