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1.
Acta Bioeng Biomech ; 26(1): 89-97, 2024 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-39219084

RESUMO

Purpose: Manual therapy is used as a conservative treatment for people with low back pain (LBP). The scale of the problem encourages the search for the most effective methods to assess of manual treatment. Therefore, the aim of the study was to investigate magnitude of changes in muscle endurance using the Biering-Sorensen test (BST) and to analyse balance in patients with LBP treated with ERS and FRS muscle energy techniques (MET). Methods: The study included fifteen men with LBP (mean age: 42 years) working as automotive assemblers. Endurance of the biceps femoris (BF), gluteus maximus (GM) and erector spinae (ES) muscles were analysed using sEMG during the BST. The level of experienced pain, degree of disability and postural stability were also examined. Results before and after a three-week treatment cycle using MET were compared. Results: The MET therapy resulted in a reduction in pain ( p = 0.001), an improvement in the degree of disability ( p < 0.001) and an increase in the duration of the BST ( p < 0.001). After therapy, the values of the NMFs parameter indicating the degree of fatigue increased, i.e., ES muscle endurance increased, both right ( p = 0.004) and left ( p < 0.001). There was also a statistically significant decrease in the centre of pressure (COP) movement velocity in balance tests. Conclusions: The use of MET in patients with LBP increases muscle endurance, improves postural balance, and reduces pain levels on the VAS and disability levels according to the ODI. MET appears to be a good tool for preventing LBP.


Assuntos
Dor Lombar , Resistência Física , Equilíbrio Postural , Humanos , Masculino , Adulto , Dor Lombar/fisiopatologia , Dor Lombar/terapia , Equilíbrio Postural/fisiologia , Resistência Física/fisiologia , Músculo Esquelético/fisiopatologia
2.
PLoS One ; 19(9): e0308373, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-39269940

RESUMO

An acute bout of exercise in the moments after learning benefits the retention of new memories. This finding can be explained, at least partly, through a consolidation account: exercise provides a physiological state that is conducive to the early stabilisation of labile new memories, which supports their retention and subsequent retrieval. The modification of consolidation through non-invasive exercise interventions offers great applied potential. However, it remains poorly understood whether effects of exercise translate from the laboratory to naturalistic settings and whether the intensity of exercise determines the effect in memory. To this end, adult endurance runners were recruited as participants and completed two study sessions spaced two weeks apart. In each session, participants were presented with a list of words and asked to recall them on three occasions: (i) immediately following their presentation, (ii) after a 30-minute retention interval, and (iii) after 24 hours. Crucially, the 30-minute retention interval comprised our experimental manipulation: higher intensity exercise (running) in the first session and lower intensity exercise (walking) in the second, both completed in a naturalistic setting around participants' existing physical activity training programmes. Exertion was recorded through heart rate and rate of perceived exertion data. Alertness, mood, and arousal ratings were also collected before and after the 30-minute retention interval. Immediate memory for the two wordlists was matched, but participants retained significantly more words after 30 minutes and 24 hours when encoding was followed by higher than lower intensity exercise. Exertion data revealed that participants experienced vigorous and light exercise in the higher and lower intensity conditions, respectively. Significant improvements in alertness, mood, and arousal were observed following both exercise conditions, but especially in the higher intensity condition. These outcomes reveal that experiencing higher intensity physical activity in the field is conducive to declarative memory retention, possibly because it encourages consolidation.


Assuntos
Memória Episódica , Resistência Física , Corrida , Humanos , Masculino , Adulto , Corrida/fisiologia , Feminino , Resistência Física/fisiologia , Exercício Físico/fisiologia , Exercício Físico/psicologia , Adulto Jovem , Frequência Cardíaca/fisiologia , Rememoração Mental/fisiologia , Afeto/fisiologia
3.
Sci Rep ; 14(1): 21304, 2024 09 12.
Artigo em Inglês | MEDLINE | ID: mdl-39266662

RESUMO

This study aimed to compare the effects of a 6-week upper body plyometric training (UBPT) on maximal strength and anaerobic power performance of male and female subjects. Forty collegiate physically active male and female subjects participated in the study and were assigned to either UBPT group (M-UBPT, n = 10, F-UBPT, n = 10) or control group (M-CON, n = 10; F-CON, n = 10). The training groups performed 6 weeks of progressive overload UBPT three times per week using six exercises and were evaluated for upper-body anaerobic power and maximal strength, 3-kg medicine ball throw (MBT), push-up endurance, and reaction time at pre- and post-intervention. After the training intervention, the M-CON and F-CON groups did not show significant (p > 0.05) changes in the variables, while both the M-UBPT and F-UBPT groups demonstrated significant (p = 0.001) medium to very large improvements in their performance as follows: maximal strength (effect size [ES] = 0.55, 0.92), MBT (ES = 1.96, 0.89) peak power output (ES = 2.31, 1.52), mean power output (ES = 2.19, 1.11), push-up endurance (ES = 1.26, 0.70), and reaction time (ES = - 2.16, - 1.56), respectively. Nevertheless, the male group experienced more significant improvements in the MBT (p = 0.001), peak (p = 0.001) and mean power output (p = 0.01), as well as reaction time (p = 0.01) compared to the female group when utilizing UBPT. In conclusion, it is imperative to take sex into account as a crucial factor when incorporating UBPT, particularly if the objective is to enhance anaerobic power output, muscular power, and reaction time.


Assuntos
Força Muscular , Exercício Pliométrico , Humanos , Feminino , Masculino , Força Muscular/fisiologia , Adulto Jovem , Exercício Pliométrico/métodos , Adaptação Fisiológica/fisiologia , Adulto , Fatores Sexuais , Resistência Física/fisiologia , Caracteres Sexuais
4.
Sci Rep ; 14(1): 21154, 2024 09 10.
Artigo em Inglês | MEDLINE | ID: mdl-39256490

RESUMO

Skeletal muscle is a highly heterogeneous tissue, and its contractile proteins are composed of different isoforms, forming various types of muscle fiber, each of which has its own metabolic characteristics. It has been demonstrated that endurance exercise induces the transition of muscle fibers from fast-twitch to slow-twitch muscle fiber type. Herein, we discover a novel epigenetic mechanism for muscle contractile property tightly coupled to its metabolic capacity during muscle fiber type transition with exercise training. Our results show that an 8-week endurance exercise induces histone methylation remodeling of PGC-1α and myosin heavy chain (MHC) isoforms in the rat gastrocnemius muscle, accompanied by increased mitochondrial biogenesis and an elevated ratio of slow-twitch to fast-twitch fibers. Furthermore, to verify the roles of reactive oxygen species (ROS) and AMPK in exercise-regulated epigenetic modifications and muscle fiber type transitions, mouse C2C12 myotubes were used. It was shown that rotenone activates ROS/AMPK pathway and histone methylation enzymes, which then promote mitochondrial biogenesis and MHC slow isoform expression. Mitoquinone (MitoQ) partially blocking rotenone-treated model confirms the role of ROS in coupling mitochondrial biogenesis with muscle fiber type. In conclusion, endurance exercise couples mitochondrial biogenesis with MHC slow isoform by remodeling histone methylation, which in turn promotes the transition of fast-twitch to slow-twitch muscle fibers. The ROS/AMPK pathway may be involved in the regulation of histone methylation enzymes by endurance exercise.


Assuntos
Histonas , Cadeias Pesadas de Miosina , Biogênese de Organelas , Coativador 1-alfa do Receptor gama Ativado por Proliferador de Peroxissomo , Condicionamento Físico Animal , Espécies Reativas de Oxigênio , Animais , Histonas/metabolismo , Camundongos , Ratos , Espécies Reativas de Oxigênio/metabolismo , Masculino , Cadeias Pesadas de Miosina/metabolismo , Coativador 1-alfa do Receptor gama Ativado por Proliferador de Peroxissomo/metabolismo , Metilação , Fibras Musculares Esqueléticas/metabolismo , Epigênese Genética , Fibras Musculares de Contração Lenta/metabolismo , Resistência Física/fisiologia , Fibras Musculares de Contração Rápida/metabolismo , Músculo Esquelético/metabolismo , Linhagem Celular , Proteínas Quinases Ativadas por AMP/metabolismo
5.
BMC Musculoskelet Disord ; 25(1): 738, 2024 Sep 14.
Artigo em Inglês | MEDLINE | ID: mdl-39277728

RESUMO

BACKGROUND: Paraspinal muscle degeneration occurs with age; however, it is unknown whether strength and endurance change with muscle cross-sectional area (CSA) and fatty infiltration (FI) parameters in Chinese healthy individuals. METHODS: A total of 94 asymptomatic Chinese volunteers were enrolled in this study. The participants were divided into three groups: young (20-39 years old, n = 27), middle-aged (40-59 years old, n = 49), and elderly (≥ 60 years old, n = 18). CSA and FI of the psoas (PS), quadratus lumborum (QL), multifidus (MF), and erector spinae (ES) were measured using magnetic resonance imaging. The Bionix Sim3 Pro was used to evaluate the maximum isometric torque and the Ito test to evaluate endurance. RESULTS: The CSA of the PS and ES in the elderly group was smaller than those in the other groups, while the CSA of QL in the young group was larger than that in the other groups. There were differences in the MF and ES FI among the three groups. The maximum isometric torque and endurance test time decreased with increasing age; however, these differences were not statistically significant. Maximum isometric torque positively correlated with the average paraspinal muscle CSA and negatively correlated with the torque and FI of the MF and ES muscles. The endurance test was found to be positively correlated with the FCSA of the MF and to be negatively correlated with the FI of the MF and ES. PS and QL can predict the maximum isometric torque, and MF and PS can predict the endurance time. CONCLUSION: MF and ES showed earlier degeneration than PS and QL. MF is the first paraspinal muscle to undergo functional area atrophy, and it plays an important role in the endurance test. The maximum moment of equal length in all directions of the lumbar spine is not completely symmetrical, but it is correlated with the imaging parameters of the paraspinal muscles. QL and PS were more activated in the lumbar activity. TRIAL REGISTRATION: The study was registered in Chinese Clinical Trial Registry and the registration number is ChiCTR2000039073 on 15/10/2020 ( https://www.chictr.org.cn/showproj.html?proj=62785 ). Ethical Approval was obtained from the Peking University Third Hospital Medical Science Research Ethics Committee (IRB00006761-M2020305).


Assuntos
Imageamento por Ressonância Magnética , Músculos Paraespinais , Adulto , Idoso , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Adulto Jovem , Fatores Etários , Envelhecimento/fisiologia , Envelhecimento/patologia , China , Estudos Transversais , Voluntários Saudáveis , Contração Isométrica/fisiologia , Força Muscular/fisiologia , Músculos Paraespinais/diagnóstico por imagem , Músculos Paraespinais/fisiologia , Resistência Física/fisiologia , Torque , População do Leste Asiático
6.
J Sports Sci Med ; 23(1): 628-637, 2024 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-39228773

RESUMO

This study aimed to explore the impact of functional training on the physical fitness of young elite field hockey players. The study comprised 40 young elite male field hockey players with the following characteristics (mean ± SD age: 21.5 ± 0.8 years; height: 176.9 ± 2.6 cm; weight: 68.4 ± 5.1 kg; BMI: 21.8 ± 1.3; training experience: 51.2 ± 5.4 months). Twenty participants were allocated to two groups: the functional training group (FTG) and the control training group (CG). Each group received 60-minute training sessions three times per week for 12 weeks. Generalized estimating equation analysis and a Bonferroni test for pairwise comparisons were used to assess the intervention's efficacy. Before the start of the exercise program, no statistically significant differences were observed in physical fitness measures between the FTG and CG (p > 0.05). However, by the sixth week, a significant difference appeared in both the T-Agility test (p < 0.001) and endurance (p = 0.024) between the two groups, while no notable distinctions were detected in other fitness parameters (p > 0.05). After a 12-week training program, the FTG demonstrated improvements in all physical fitness measures [flexibility (p < 0.001); Illinois agility test (p < 0.001); T-agility test (p = 0.020); endurance (p < 0.001)] except speed, which exhibited no significant impact (p = 0.175). Notable enhancements in T-agility and endurance were evident after just six weeks of functional training, and a 12-week functional training regimen showed superiority over standard training approaches in young elite male field hockey players. These findings encourage the efficacy of functional training exercises over traditional methods in enhancing athletes' fitness parameters.


Assuntos
Hóquei , Aptidão Física , Humanos , Hóquei/fisiologia , Masculino , Aptidão Física/fisiologia , Adulto Jovem , Condicionamento Físico Humano/métodos , Resistência Física/fisiologia , Força Muscular/fisiologia , Desempenho Atlético/fisiologia
7.
Dev Neurorehabil ; 27(7): 235-242, 2024 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-39311681

RESUMO

PURPOSE: This pilot study assessed the safety and effects of progressive functional high-intensity training in a group setting for adolescents with unilateral cerebral palsy (CP) on daily function indicators. METHODS: Nine adolescents (mean age 16.9 years, GMFCS levels I-II) participated in 12 weeks of training (2x/week). Evaluations included 3D gait analysis, the 6-min walking test (6MWT), clinical exams, and the Gross Motor Function Measure-66 (GMFM-66). RESULTS: No adverse events occurred, and GMFM-66 scores significantly improved (p = .031, Δ = 2.19%). Although increases in 6MWT (p = .09, Δ = 29.8 m) performance and propulsion ratio (p = .067, Δ = 5.4%) for the affected leg were observed, they were not statistically significant. DISCUSSION: The study suggests that this training is safe and may enhance gross motor function, endurance, and gait asymmetry in unilateral CP. Future research should include upper limb evaluations and out-of-clinic motion analysis with wearable inertial measurement units (IMUs) to provide a more comprehensive assessment of functional movements.


Assuntos
Paralisia Cerebral , Humanos , Paralisia Cerebral/reabilitação , Paralisia Cerebral/fisiopatologia , Projetos Piloto , Adolescente , Masculino , Feminino , Adulto Jovem , Marcha/fisiologia , Resistência Física/fisiologia , Treinamento Intervalado de Alta Intensidade/métodos , Terapia por Exercício/métodos , Resultado do Tratamento
8.
Medicine (Baltimore) ; 103(38): e39734, 2024 Sep 20.
Artigo em Inglês | MEDLINE | ID: mdl-39312369

RESUMO

BACKGROUND: Low back pain (LBP) is a global musculoskeletal ailment. Over the past few years, dry needling (DN) has garnered interest from both physical therapists and patients. Physical therapy commonly employs spinal manipulation to alleviate persistent LBP and other musculoskeletal disorders. The aim of this study was to investigate the effects of spinal manipulation alone and in combination with DN on functional disability and endurance in individuals suffering from chronic nonspecific LBP. METHODS: Patients of both genders who had chronic nonspecific LBP and who had not received physical therapy within the last 3 months were included in this single-blind, randomized controlled trial using purposive sampling. All participants were randomly assigned to either the experimental (SMT + DN) or control (SMT alone) group using computer-generated random numbers. The data were analyzed using the Statistical Package for Social Sciences (SPSS) version 23.0. For between-group comparisons, the Mann-Whitney U test was used. A P-value < .05 was considered to indicate statistical significance. RESULTS: The analysis of the difference between the 2 groups revealed that the mean ±â€…standard deviation (SD) for the SMT alone group was 16.09 ±â€…3.963 at baseline and 12.66 ±â€…3.801 at 8 weeks, whereas for the DN + ST group, it was 13.67 ±â€…3.904 at baseline and 10.92 ±â€…3.534 at 8 weeks, with a P-value of .003. Thus, the RMDQ score improved gradually in both groups, and the mean endurance score reported for the ST group was 2.5 to 4.5, while that reported for the DN + ST group was 3.1 to 5.1. CONCLUSION: The results of this study showed that both therapies effectively reduced LBP. When comparing the effects of spinal manipulation alone to those of spinal manipulation combined with DN, the latter showed significantly greater benefits.


Assuntos
Agulhamento Seco , Dor Lombar , Manipulação da Coluna , Humanos , Dor Lombar/terapia , Masculino , Feminino , Método Simples-Cego , Manipulação da Coluna/métodos , Adulto , Agulhamento Seco/métodos , Pessoa de Meia-Idade , Avaliação da Deficiência , Dor Crônica/terapia , Resultado do Tratamento , Resistência Física/fisiologia , Terapia Combinada , Medição da Dor
9.
J Int Soc Sports Nutr ; 21(1): 2400513, 2024 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-39246027

RESUMO

BACKGROUND: Caffeine is one of the most popular ergogenic aids consumed by athletes. Caffeine's ergogenic effect has been generally explained by its ability to bind to adenosine receptors, thus modulating pain and reducing perceived exertion. Another pharmacological agent that may improve performance due to its analgesic proprieties is paracetamol. This study aimed to explore the effects of caffeine, paracetamol, and caffeine + paracetamol consumption on muscular endurance, strength, power, anaerobic endurance, and jumping performance. METHODS: In this randomized, crossover, double-blind study, 29 resistance-trained participants (11 men and 18 women) ingested either a placebo, caffeine (3 mg/kg), paracetamol (1500 mg) or caffeine + paracetamol 45 min before the testing sessions. The testing sessions included performing the bench press exercise with 75% of one-repetition maximum to momentary muscular failure, isokinetic knee extension and flexion at angular velocities of 60°/sec and 180°/sec, Wingate, and countermovement jump (CMJ) tests. RESULTS: Compared to placebo, isolated caffeine ingestion increased the number of repetitions performed in the bench press (p = 0.005; d = 0.42). Compared to placebo, isolated caffeine ingestion and/or caffeine + paracetamol consumption was ergogenic for strength (torque), muscular endurance (total work), or power in the isokinetic assessment, particularly at slower angular velocities (p = 0.027 to 0.002; d = 0.16 to 0.26). No significant differences between the conditions were observed for outcomes related to the Wingate and CMJ tests. CONCLUSION: This study provided novel evidence into the effectiveness of caffeine, paracetamol, and their combination on exercise performance. We found improvements in muscular endurance, strength, or power only when caffeine was consumed in isolation, or in combination with paracetamol. Isolated paracetamol consumption did not improve performance for any of the analyzed outcomes, thus calling into question its ergogenic potential.


Assuntos
Acetaminofen , Cafeína , Estudos Cross-Over , Força Muscular , Substâncias para Melhoria do Desempenho , Resistência Física , Humanos , Cafeína/administração & dosagem , Cafeína/farmacologia , Acetaminofen/farmacologia , Acetaminofen/administração & dosagem , Método Duplo-Cego , Masculino , Força Muscular/efeitos dos fármacos , Resistência Física/efeitos dos fármacos , Resistência Física/fisiologia , Feminino , Adulto Jovem , Substâncias para Melhoria do Desempenho/administração & dosagem , Substâncias para Melhoria do Desempenho/farmacologia , Adulto , Treinamento Resistido , Músculo Esquelético/efeitos dos fármacos , Músculo Esquelético/fisiologia , Desempenho Atlético/fisiologia
10.
Ecol Evol Physiol ; 97(4): 191-208, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-39270325

RESUMO

AbstractMuscle-tendon unit (MTU) morphology and physiology are likely major determinants of locomotor performance and therefore Darwinian fitness. However, the relationships between underlying traits, performance, and fitness are complicated by phenomena such as coadaptation, multiple solutions, and trade-offs. Here, we leverage a long-running artificial selection experiment in which mice have been bred for high levels of voluntary running to explore MTU adaptation, as well as the role of coadaptation, multiple solutions, and trade-offs, in the evolution of endurance running. We compared the morphological and contractile properties of the triceps surae complex, a major locomotor MTU, in four replicate selected lines to those of the triceps surae complex in four replicate control lines. All selected lines have lighter and shorter muscles, longer tendons, and faster muscle twitch times than all control lines. Absolute and normalized maximum shortening velocities and contractile endurance vary across selected lines. Selected lines have similar or lower absolute velocities and higher endurance than control lines. However, normalized shortening velocities are both higher and lower in selected lines than in control lines. These findings potentially show an interesting coadaptation between muscle and tendon morphology and muscle physiology, highlight multiple solutions for increasing endurance running performance, demonstrate that a trade-off between muscle speed and endurance can arise in response to selection, and suggest that a novel physiology may sometimes allow this trade-off to be circumvented.


Assuntos
Adaptação Fisiológica , Músculo Esquelético , Resistência Física , Corrida , Tendões , Animais , Camundongos , Corrida/fisiologia , Tendões/fisiologia , Resistência Física/genética , Resistência Física/fisiologia , Músculo Esquelético/fisiologia , Adaptação Fisiológica/fisiologia , Evolução Biológica , Masculino , Feminino , Contração Muscular/fisiologia
11.
PLoS One ; 19(9): e0307325, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-39240856

RESUMO

Determining an athlete's maximal peak power (MPP) is crucial in profiling endurance sports participants. While short (3 to 6 seconds) all-out efforts have been validated for MPP assessment, prior studies mainly involved non-endurance trained athletes. This study aimed to assess the intra- and inter-day reliability of a 6-second Wingate test for MPP determination in endurance athletes. Endurance-trained participants (22 males, 5 females) completed nine 6-second Wingate tests over four days (3 trials at baseline, 2 trials on each subsequent day). Analysis revealed no systematic differences in MPP (F(4.09, 106.3) = 1.88, p = 0.117) or time to peak power (χ2 (8) = 5.23, p = 0.732) across the trials. Reliability, assessed through the intraclass correlation coefficient (ICC) and standard error of measurement (SEM), was excellent across all trials (ICC = 0.95, SEM = 40.0W, SEM% = 3.7%). Absolute reliability improved when selecting the average or the best MPP values from each day (SEM% = 2.7% and 2.9%, respectively). Within-day reliability was consistently rated as excellent, with the best values on the 4th day of tests. No significant differences in MPP values occurred between the first and second 6-second Wingate tests on days 1 to 3, with both trials demonstrating similar reliability values (SEM%: 3.2% vs 2.8%, for the first and second trials, respectively). The test also demonstrated a good sensitivity to detect a meaningful change in MPP values. In conclusion, the 6-second Wingate test proves reliable for determining MPP in endurance-trained athletes. Two trials are recommended on the first day of testing, with a single MPP likely sufficient to determine the athlete's MPP on subsequent days.


Assuntos
Atletas , Teste de Esforço , Resistência Física , Humanos , Masculino , Feminino , Resistência Física/fisiologia , Reprodutibilidade dos Testes , Adulto , Teste de Esforço/métodos , Adulto Jovem
12.
Sci Rep ; 14(1): 20450, 2024 09 03.
Artigo em Inglês | MEDLINE | ID: mdl-39242762

RESUMO

30 min of moderate-intensity aerobic exercise per day is recommended, but the response and adaptation of endothelial function (EF) to this exercise remains controversial. The purpose of this study was to determine the changes in EF in endurance trained and untrained individuals before and after this exercise and to compare the differences between trained and untrained individuals. Twelve endurance-trained male college athletes (trained group) and 12 untrained male college students (untrained group) performed a 30-min run at an intensity of 60% VO2max. Brachial artery flow-mediated dilation (FMD) was measured before exercise, 30 min and 60 min after exercise, and the following morning. Resting diameter and maximum diameter showed large time effects (p < 0.001, η2 = 0.533; p < 0.001, η2 = 0.502). Resting diameters at 30 and 60 min after exercise were higher than before exercise in both the untrained and trained groups (p < 0.05), and maximum diameters at 30 min after exercise were higher than before exercise in both the untrained and trained groups (p < 0.01). Resting diameter and maximum diameter also exhibited some group effects (p = 0.055, η2 = 0.157; p = 0.041, η2 = 0.176). Resting diameters and maximum diameters were higher in the trained group than in the untrained group before exercise (p < 0.05). FMD (%) showed no time, group, or time-group interaction effects. 30 min of moderate-intensity aerobic exercise can increase resting and maximal arterial diameters in both trained and untrained young men, but has no effect on FMD. Long-term endurance training has the potential to increase resting and maximal arterial diameters in young men, but not necessarily FMD.


Assuntos
Artéria Braquial , Endotélio Vascular , Exercício Físico , Vasodilatação , Humanos , Masculino , Exercício Físico/fisiologia , Endotélio Vascular/fisiologia , Adulto Jovem , Artéria Braquial/fisiologia , Vasodilatação/fisiologia , Adulto , Atletas , Resistência Física/fisiologia
13.
J Cardiovasc Med (Hagerstown) ; 25(10): 731-739, 2024 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-39225077

RESUMO

BACKGROUND: Supraventricular extra beats (SVEB) are frequently observed in athletes but data on significance, prognostic role and correlation with cardiac remodeling are contrasting. It is uncertain whether SVEB may indicate the development of more complex arrhythmias and the need for closer monitoring is undetermined. The aim was to assess the prevalence and clinical significance of BESV in Olympic athletes of different sporting disciplines, evaluating potential correlations with cardiac remodeling and clinical features. METHODS: We enrolled athletes who participated at 2012-2022 Olympic Games, submitted to physical examination, blood tests, echocardiography and exercise tests, categorized into power, skills, endurance and mixed disciplines. RESULTS: We studied 1492 elite athletes: 56% male individuals, mean age 25.8 ±â€Š5.1 years; 29.5% practiced power, 12.3% skills, 21% endurance and 37.2% mixed disciplines. At exercise-stress tests, 6.2% had SVEB, mostly single beats. SVEB were not influenced by anthropometrics or blood test results. They were more common in male individuals (77.4 vs. 54.6%, P < 0.0001) and older athletes (27.1 ±â€Š5.7 vs. 25.7 ±â€Š5.1, P = 0.01). In male athletes with SVEB, higher left atrial volumes were observed (24.2 ±â€Š7.3 vs. 22.2 ±â€Š7.1 ml/m2, P = 0.03). No differences were found in terms of sporting discipline: despite larger left atrial dimensions in aerobic disciplines, SVEB rates were similar in different sporting disciplines (6.1% endurance, 6.3% mixed, 5.2% power and 8.7% skills; P = 0.435). CONCLUSION: SVEB were more common in older, male athletes and associated with higher left atrial volume (especially in male individuals) regardless of sport practiced. Athletes with greater left atrial volume and SVEB are supposed to have higher risk, in middle age, of developing more complex arrhythmias.


Assuntos
Atletas , Humanos , Masculino , Adulto , Atletas/estatística & dados numéricos , Adulto Jovem , Feminino , Prevalência , Esportes/fisiologia , Esportes/estatística & dados numéricos , Remodelação Ventricular , Complexos Atriais Prematuros/fisiopatologia , Complexos Atriais Prematuros/diagnóstico , Complexos Atriais Prematuros/epidemiologia , Fatores de Risco , Ecocardiografia , Frequência Cardíaca , Teste de Esforço , Estudos Transversais , Resistência Física/fisiologia
14.
Int J Sports Physiol Perform ; 19(10): 1137-1147, 2024 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-39142645

RESUMO

PURPOSE: To profile the training characteristics of an elite team pursuit cycling squad and assess variations in training intensity and load accumulation across the 36-week period prior to a world-record performance at the 2018 Commonwealth Games. METHODS: Training data of 5 male track endurance cyclists (mean [SD]; age 21.9 [3.52] y; 4.4 [0.16] W·kg-1 at anaerobic threshold; 6.2 [0.28] W·kg-1 maximal oxygen uptake 68.7 [2.99] mL kg·min-1) were analyzed with weekly total training volume and heart rate, power output, and torque intensity distributions calculated with reference to their 3:49.804 min:s.ms performance requirements for a 4-km team pursuit. RESULTS: Athletes completed 543 (37) h-1 of training across 436 (16) sessions. On-bike activities accounted for 69.9% of all training sessions, with participants cycling 11,246 (1139) km-1 in the training period of interest, whereas 12.7% of sessions involved gym/strength training. A pyramidal intensity distribution was evident with over 65% and 70% of training, respectively, performed at low-intensity zone heart rate and power output, whereas 5.3% and 7.7% of training was performed above anaerobic threshold. The athletes accumulated 4.4% of total training volume at, or above, their world-record team pursuit lead position torque (55 N·m). CONCLUSIONS: These data provide updated and novel insight to the power and torque demands and load accumulation contributing to world-record team pursuit performance. Although the observed pyramidal intensity distribution is common in endurance sports, the lack of shift toward a polarized intensity distribution during taper and competition peaking differs from previous research.


Assuntos
Ciclismo , Frequência Cardíaca , Consumo de Oxigênio , Condicionamento Físico Humano , Humanos , Masculino , Ciclismo/fisiologia , Condicionamento Físico Humano/métodos , Adulto Jovem , Frequência Cardíaca/fisiologia , Consumo de Oxigênio/fisiologia , Desempenho Atlético/fisiologia , Limiar Anaeróbio/fisiologia , Torque , Resistência Física/fisiologia , Adulto , Treinamento Resistido/métodos , Esportes de Equipe
15.
Medicina (Kaunas) ; 60(8)2024 Aug 14.
Artigo em Inglês | MEDLINE | ID: mdl-39202597

RESUMO

Background and Objectives: Compared to other subjects, obese people have inferior trunk muscle endurance and balance. A modern method of neuro-muscular training called whole body vibration (WBV) may improve trunk muscle endurance and balance. This study evaluates the impact of a 4-week WBV program on trunk endurance and balance in obese female students. Materials and Methods: Sixty participants from 18 to 25 years of age and with BMI values ≥ 30 were randomly distributed into two equal groups: Group A (WBV group), who received 4 min of WBV, and Group B (sham WBV group), who received WBV with a turn-off device. The training was conducted two days/week for six weeks. Trunk endurance was evaluated using the Sorensen Test (ST) and Trunk Flexor Endurance Test (TFET). The Single-Leg Test (SLT) was used to assess static balance, while the Biodex Stability System measured dynamic balance. Results: The current study demonstrated no significant differences (p > 0.05) in pre-treatment variables between Groups A and B. Post-treatment, Group A showed a significantly higher duration of the Sorensen test, TFET and SLS than Group B (p < 0.001). Moreover, Group A showed significantly lower dynamic balance (p < 0.001) than Group B. Conclusions: WBV has a short-term effect on trunk endurance and balance in obese female students. WBV can be added to the rehabilitation program for obese subjects with deficits in trunk endurance and balance.


Assuntos
Obesidade , Resistência Física , Equilíbrio Postural , Vibração , Humanos , Feminino , Vibração/uso terapêutico , Equilíbrio Postural/fisiologia , Obesidade/fisiopatologia , Obesidade/terapia , Adulto , Adolescente , Resistência Física/fisiologia , Adulto Jovem , Estudantes/estatística & dados numéricos , Tronco/fisiologia , Tronco/fisiopatologia
17.
Int J Sports Physiol Perform ; 19(10): 1148-1157, 2024 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-39142644

RESUMO

PURPOSE: To compare the training characteristics of an elite team pursuit cycling squad in the 3-month preparation phases prior to 2 successive world-record (WR) performances. METHODS: Training data of 5 male track endurance cyclists (mean [SD]; age 23.4 [3.46] y; body mass 80.2 [2.74] kg; 4.5 [0.17] W·kg-1 at LT2; maximal aerobic power 6.2 [0.27] W·kg-1; maximal oxygen uptake 65.9 [2.89] mL·kg-1·min-1) were analyzed with weekly total training volume by training type and heart rate, power output, and torque intensity distributions calculated with reference to the respective WRs' performance requirements. RESULTS: Athletes completed 805 (82.81) and 725 (68.40) min·wk-1 of training, respectively, in each season. In the second season, there was a 32% increase in total track volume, although track sessions were shorter (ie, greater frequency) in the second season. A pyramidal intensity distribution was consistent across both seasons, with 81% of training, on average, performed below LT1 power output each week, whereas 6% of training was performed above LT2. Athletes accumulated greater volume above WR team pursuit lead power (2.4% vs 0.9%) and torque (6.2% vs 3.2%) in 2019. In one athlete, mean single-leg-press peak rate of force development was 71% and 46% higher at mid- and late-phases, respectively, during the preparation period. CONCLUSIONS: These findings provide novel insights into the common and contrasting methods contributing to successive WR team pursuit performances. Greater accumulation of volume above race-specific power and torque (eg, team pursuit lead), as well as improved neuromuscular force-generating capacities, may be worthy of investigation for implementation in training programs.


Assuntos
Desempenho Atlético , Ciclismo , Frequência Cardíaca , Consumo de Oxigênio , Condicionamento Físico Humano , Humanos , Masculino , Ciclismo/fisiologia , Desempenho Atlético/fisiologia , Condicionamento Físico Humano/métodos , Adulto Jovem , Frequência Cardíaca/fisiologia , Torque , Adulto , Resistência Física/fisiologia , Força Muscular/fisiologia , Comportamento Competitivo/fisiologia , Esportes de Equipe
18.
Nutrients ; 16(16)2024 Aug 17.
Artigo em Inglês | MEDLINE | ID: mdl-39203884

RESUMO

Plant-based protein supplements are increasingly popular, yet their efficacy in enhancing athletic performance compared to animal protein, insect protein, or other protein types remains under investigation. This study aimed to assess the effectiveness of plant-based protein on athletic abilities such as muscle strength, endurance performance, and muscle protein synthesis (MPS) rate and compare it to no- or low-protein ingestion and non-plant protein sources. Randomized controlled trials (RCTs) evaluating the beneficial and harmful effects of plant-based protein ingestion on athletic ability in healthy individuals were considered. A systematic search of six databases yielded 2152 studies, which were screened using the Covidence systematic review tool. Thirty-one studies were included for meta-analysis after independent selection, data extraction, and risk of bias assessment by two reviewers. The meta-analysis employed a Bayesian approach using the Markov chain Monte Carlo (MCMC) method through a random-effects model. The results demonstrated that plant-based protein supplements provided greater benefits for athletic performance in healthy individuals compared to the no- or low-protein ingestion group [µ(SMD): 0.281, 95% CI: 0.159 to 0.412; heterogeneity τ: 0.18, 95% CI: 0.017 to 0.362]. However, when compared to other types of protein, plant-based protein ingestion was less effective in enhancing athletic ability [µ(SMD): -0.119, 95% CI: -0.209 to -0.028; heterogeneity τ: 0.076, 95% CI: 0.003 to 0.192]. A subgroup analysis indicated significant improvements in muscle strength and endurance performance in both young and older individuals consuming plant-based protein compared to those with no- or low-protein ingestion. Nonetheless, other protein types showed greater benefits in muscle strength compared to plant-based protein [µ(SMD): -0.133, 95% CI: -0.235 to -0.034; heterogeneity τ: 0.086, 95% CI: 0.004 to 0.214]. In conclusion, while plant-based protein ingestion demonstrates superior efficacy compared to low- or no-protein ingestion, it is not as effective as other protein types such as whey, beef, or milk protein in enhancing athletic performance in healthy individuals. Registration: Registered at the International Prospective Register of Systematic Reviews (PROSPERO) (identification code CRD42024555804).


Assuntos
Desempenho Atlético , Suplementos Nutricionais , Força Muscular , Proteínas de Vegetais Comestíveis , Humanos , Desempenho Atlético/fisiologia , Teorema de Bayes , Proteínas Musculares/biossíntese , Força Muscular/efeitos dos fármacos , Força Muscular/fisiologia , Resistência Física/efeitos dos fármacos , Proteínas de Vegetais Comestíveis/administração & dosagem , Ensaios Clínicos Controlados Aleatórios como Assunto
19.
Psychol Sport Exerc ; 75: 102720, 2024 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-39181418

RESUMO

BACKGROUND: Mental fatigue, elicited by cognitive demands, can impair sport and exercise performance. The effects of isolated mental fatigue on performance are well documented but few studies have explored the effects of combined mental and physical fatigue on skilled motor and endurance exercise performance. OBJECTIVE: This study explored the effects of isolated mental, isolated physical, and combined (mental plus physical) fatigue on skill and exercise task performance. METHOD: 164 athletes were randomly assigned to 1 of 4 groups: mental fatigue, physical fatigue, combined fatigue, control (no fatigue). Mental fatigue was induced by a 15-min time-load dual-back cognitive task. Physical fatigue was induced by a 90-s burpee exercise task. Next, all participants completed a throwing skill task and performed burpee exercises to failure. Objective (brief Psychomotor Vigilance Task, PVT-B) and subjective (self-report) measures of mental fatigue and Ratings of Perceived Exertion were obtained throughout. RESULTS: The mental fatigue and combined fatigue groups performed the worst on both the throwing and burpee tasks compared with the physical fatigue and control groups. The former reported higher mental fatigue throughout and had worse response accuracy and variation on the end-of-session PVT-B task. The combined fatigue group performed better than the mental fatigue group on the throwing and burpee tasks. CONCLUSION: A demanding cognitive task induced a state of mental fatigue and impaired skill and endurance performance. Mental fatigue alone was more detrimental than combined fatigue to skill and endurance performance, suggesting that the physical activity manipulation reduced the negative effects of mental fatigue on performance.


Assuntos
Fadiga , Fadiga Mental , Destreza Motora , Resistência Física , Humanos , Fadiga Mental/fisiopatologia , Masculino , Resistência Física/fisiologia , Feminino , Destreza Motora/fisiologia , Adulto Jovem , Fadiga/fisiopatologia , Fadiga/psicologia , Desempenho Atlético/fisiologia , Desempenho Atlético/psicologia , Adulto , Desempenho Psicomotor/fisiologia , Exercício Físico/fisiologia , Exercício Físico/psicologia
20.
PeerJ ; 12: e17863, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-39193515

RESUMO

Background: Long-term adaptations and ongoing training seem to modify the energy system contribution in highly trained individuals. We aimed to compare the energy metabolism profile during sprint exercise in athletes of different specialties. Methods: Endurance (n = 17, 20.3 ± 6.0 yrs), speed-power (n = 14, 20.3 ± 2.5 yrs), and mixed (n = 19, 23.4 ± 4.8 yrs) athletes performed adapted 15-second all-out test before and after a general preparation training period. The contribution of phosphagen, glycolytic, and aerobic systems was calculated using the three-component PCr-LA-O2 method. Results: Between-group differences were observed in the contribution of energy systems in the first and second examinations. The proportions were 47:41:12 in endurance, 35:57:8 in team sports, and 45:48:7 in speed-power athletes. Endurance athletes differed in the phosphagen (p < 0.001) and glycolytic systems (p = 0.006) from team sports and in the aerobic system from speed-power athletes (p = 0.003). No substantial shifts were observed after the general preparatory phase, except a decrease in aerobic energy contribution in team sports athletes (p = 0.048). Conclusion: Sports specialization and metabolic profile influence energy system contribution during sprint exercise. Highly trained athletes show a stable energy profile during the general preparation phase, indicative of long-term adaptation, rather than immediate training effects.


Assuntos
Atletas , Metabolismo Energético , Humanos , Metabolismo Energético/fisiologia , Masculino , Adulto Jovem , Adulto , Corrida/fisiologia , Resistência Física/fisiologia , Adaptação Fisiológica/fisiologia , Feminino , Adolescente , Glicólise/fisiologia , Consumo de Oxigênio/fisiologia
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