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1.
Phytother Res ; 37(10): 4414-4428, 2023 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-37495266

RESUMO

The aim of this systematic review was to determine whether the supplementation with Rhodiola rosea (RR), an herb that has been used for centuries for its various properties, can have an effect on muscle damage and physical performance. The databases PubMed, Web of Science, and Cochrane Library were used to find studies published until March 2023. Randomized controlled trials, healthy participants, and no use of other supplements. The search strategy was conducted by two independent reviewers, and specific information was extracted from the selected studies. Thirteen studies were included with 263 participants (198 men and 65 women between 18 and 65 years old). Two studies followed acute supplementation, 5 chronic, and 6 combined both. The results were heterogenous, having 11 studies with some positive effects, while 2 studies show no effect in variables such as rating of perceive exertion, heart rate, antioxidant capacity, blood lactate, creatine kinase, or C-reactive protein. Two limitations were found, firstly, the difference between supplementation and exercise protocols, and secondly, the existence of unclear or high risk of bias in most of the studies included. Acute supplementation with RR has a positive effect on endurance performance and rating of perceived exertion (RPE). Chronic supplementation has a positive effect on anaerobic exercise performance, but not endurance exercise performance. Chronic supplementation may positively impact muscle damage during exercise. However, more high-quality studies are needed to firmly establish the clinical efficacy of RR.


Assuntos
Rhodiola , Adolescente , Adulto , Idoso , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Adulto Jovem , Antioxidantes , Suplementos Nutricionais , Exercício Físico/fisiologia , Ensaios Clínicos Controlados Aleatórios como Assunto
2.
Int J Sports Med ; 44(12): 871-881, 2023 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-37524114

RESUMO

The purpose of this study was to evaluate young male and female handball players' perceptions of the bio-banding concept. The estimated biological maturity status was assessed in a sample of 46 male and 40 female handball players (aged 14.06±1.40 years), who competed in both an annual age-group and bio-banded tournament. To test the players' perception of bio-banding, a post-competition questionnaire was conducted. A series of ANOVA and one-sample t-tests were used in order to examine the differences in perception between the different maturity groups. An inductive thematic analysis of the qualitative data recorded in the open-ended questions was also carried out. The results showed that early-maturing boys enjoyed the bio-banding tournament more than late-maturing boys (p<0.05). Conversely, no differences were found in girls (p>0.05). Furthermore, discussions were conducted based on the qualitative analysis of the players' written comments regarding their overall experience, finding individual variance in biological maturity may be less relevant in female sports contexts due to gender-related differences. Thus, a greater influence on play and leadership in late maturing boys and early maturing girls, a greater physical challenge in early maturing boys and an opportunity to express themselves technically and tactically in late maturing boys and on-time maturing girls were observed. Therefore, stakeholders must consider the different consequences of bio-banding in order to maximize the athlete's sport development process.


Assuntos
Esportes , Humanos , Masculino , Feminino , Antropometria/métodos , Estatura
3.
J Strength Cond Res ; 36(12): 3562-3570, 2022 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-36417361

RESUMO

ABSTRACT: Anderson, OK, Martinez-Ferran, M, Lorenzo-Calvo, J, Jiménez, SL, and Pareja-Galeano, H. Effects of nitrate supplementation on muscle strength and mass: a systematic review. J Strength Cond Res 36(12): 3562-3570, 2022-This systematic review examines the effect of dietary nitrate supplementation (SUP) on muscle strength and hypertrophy when combined with physical exercise. The databases PubMed, Web of Science, and MEDLINE were searched for full-text articles published between January 2000 and June 2020. For inclusion, studies had to report on the effects of SUP administered as acute or chronic doses together with a standardized exercise protocol on muscle strength and hypertrophy compared with placebo in healthy adults who were sedentary, physically active, or professional athletes. Twelve studies (1,571 subjects) were finally selected. In 5 studies, the SUP regime was acute, and in 7, it was chronic. SUP was nitrate-rich beetroot juice in 9 studies, a potassium nitrate capsule in 1, and increased dietary nitrate in 2. Ingested nitrate was 64-1,200 mg. Of the 12 studies, 6 observed an ergogenic effect of SUP compared with placebo. These findings indicate that muscle strength gains are possible provided the dose, format, frequency, period, and exercise test are appropriate. Best results were observed with a minimum acute dose of 400 mg of nitrate provided as beetroot juice/shot taken 2-2.5 hours before exercise involving low- and high-intensity muscle contractions. This SUP regime seems to improve muscle efficiency in terms of reduced phosphocreatine and energy costs (P-magnetic resonance spectroscopy) and improved time to exhaustion.


Assuntos
Músculo Esquelético , Nitratos , Adulto , Humanos , Nitratos/farmacologia , Músculo Esquelético/fisiologia , Suplementos Nutricionais , Força Muscular , Hipertrofia
4.
Phys Ther Sport ; 63: 9-16, 2023 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-37413954

RESUMO

OBJECTIVES: To investigate the influence of the gender, ranking and playing position on the musculoskeletal injuries in professional padel players. DESIGN: An epidemiological, observational, descriptive, retrospective cross-sectional study. PARTICIPANTS: 44 injuries were reported by 36 players (20 men/16 women) who participated in the World Padel Tour 2021. SETTING: Online questionnaire. MAIN OUTCOME MEASURE: Descriptive statistics and injury prevalence were calculated. Spearman/Pearson correlations between sample characteristics and injury variables were calculated. The chi-square test was used to analyse the association between injury and descriptive variables. A Mann-Whitney U test was performed to compare the group differences with regard to days of absence. RESULTS: The results showed different injury prevalence (x1000 matches) in male (10.50) and female players (15.10). A higher injury incidence in top-ranked players, both in male (44.40%) and female (58.33%) was identified, but the low-ranked players reported more severe injuries (>28 days) (p < 0.05). Top-ranked players suffered more muscle injuries (p < 0.01) and low-ranked players suffered more tendon injuries (p < 0.01). Gender, ranking and playing position did not influence the days of absence (p > 0.05). CONCLUSIONS: This study confirms that gender and ranking position had an impact on the injury prevalence in professional padel players.


Assuntos
Traumatismos em Atletas , Feminino , Humanos , Masculino , Traumatismos em Atletas/epidemiologia , Estudos Transversais , Incidência , Prevalência , Estudos Retrospectivos , Estações do Ano
5.
Sports (Basel) ; 11(3)2023 Mar 13.
Artigo em Inglês | MEDLINE | ID: mdl-36976953

RESUMO

(I) The execution of different sports involves a significant number of throws, jumps, or direction changes, so the body must be as stable as possible while performing a specific action. However, there is no classification of unstable devices and their influence on performance variables. Furthermore, the effect on athletes' experience using instability is unknown. (II) The aim of this study was to analyze the power and speed parameters in bench press with different loads and unstable executions: (1) stable (SB), (2) with asymmetric load (AB), (3) with unstable load (UB), (4) on fitball (FB) and (5) on a Bosu® (BB). A total of 30 male participants (15 trained and 15 untrained) were evaluated for mean propulsive speed (MPS), maximum speed (MS), and power (PW) with different types of external load: a low load (40% of 1RM), medium load (60% of 1RM), and high load (80% of 1RM) in each condition. Variables were measured with an inertial dynamometer. (III) The best data were evidenced with SB, followed by AB (3-12%), UB (4-11%), FB (7-19%), and BB (14-23%). There were no differences between groups and loads (p > 0.05) except in the case of MS with 60% 1RM, where trained participants obtained 4% better data (p < 0.05). (IV) Executions with implements and equipment such as fitball and Bosu® do not seem to be the most recommended when the objective is to improve power or execution speed. However, situations where the load is unstable (AB and UB) seem to be a good alternative to improve stabilization work without high performance. Furthermore, experience does not seem to be a determining factor.

6.
Artigo em Inglês | MEDLINE | ID: mdl-36360619

RESUMO

(I) Training in unstable conditions, with different elements, platforms, or situations, has been used because there is a significant increase in muscle activation, balance, proprioception, and even sports performance. However, it is not known how the devices used are classified according to performance variables, nor the differences according to instability experience. (II) This study aims to analyze the differences in power and speed in push-ups with different situations of instability in trained and untrained male subjects. Power and speed in push-up exercise were analyzed in 26 untrained and 25 trained participants in 6 different situations (one stable and five unstable) (1) stable (PS), (2) monopodal (PM), (3) rings (PR), (4) TRX® (PT), (5) hands-on Bosu® (PH) (6) feet on Bosu® (PF). The variables were analyzed using a linear position transducer. (III) The best data were evidenced with PS, followed by PR, PM, PT, PH and PF. The trained subjects obtained better results in all the conditions analyzed in mean and maximum power and speed values (p < 0.001). The decrease in these variables was significantly greater in the untrained subjects than in the trained subjects in the PR situation (8% and 18% respectively). In PF there were differences between groups (p < 0.001), reaching between 32-46% in all variables. The difference between the two groups was notable, varying between 12-58%. (IV) The results showed a negative and progressive influence of instability on power and speed in push-ups. This suggests that instability should be adapted to the subject's experience and is not advisable in untrained subjects who wish to improve power.


Assuntos
Desempenho Atlético , Músculo Esquelético , Humanos , Masculino , Músculo Esquelético/fisiologia , Desempenho Atlético/fisiologia , Exercício Físico/fisiologia , Adaptação Fisiológica , Força Muscular/fisiologia
7.
Artigo em Inglês | MEDLINE | ID: mdl-36497971

RESUMO

This review analyzed the effects of an exercise program on psychoemotional and quality-of-life (QoL) factors in adult patients with cancer and hematopoietic stem cell transplantation (HSCT) or bone marrow transplantation (BMT). Studies were identified from the PubMed and Web of Science databases (from inception to 24 August 2022), according to the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) checklist. The methodological quality of the included studies was assessed with the Physiotherapy Evidence Database (PEDro) scale, based in turn on the Delphi list. A total of 20 randomized controlled studies were included with 1219 participants. The main result of this systematic review is that exercise program interventions produce improvements on psychoemotional and QoL factors in adult patients with cancer and HSCT or BMT. Moreover, exercise programs may have a beneficial effect on health, maintaining or increasing the patient's QoL. Further, it has a positive effect on the prevention and control of transplant complications in combination with medical treatment.


Assuntos
Transplante de Células-Tronco Hematopoéticas , Neoplasias , Humanos , Adulto , Transplante de Medula Óssea , Qualidade de Vida , Neoplasias/terapia , Terapia por Exercício
8.
Nutrients ; 14(19)2022 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-36235737

RESUMO

Previous studies have shown that polyphenol consumption enhances recovery of the muscle after exercise-induced muscle damage (EIMD). However, EIMD markers have not been studied by sport type. The main aim of this research was to perform a systematic review to determine the efficacy of polyphenolic consumption in increasing muscle recovery for performing team sport skills. Eligible studies included, following PICOS structure, presented at least one of the following outcomes: maximal isometric voluntary contraction (MVIC); countermovement jump (CMJ); delayed onset muscle soreness (DOMS); 20 m sprint test; creatine kinase (CK); and C-reactive protein (hsCRP). A structured search was carried out following the Preferred Reporting Items for Systematic Review and Meta-Analyses (PRISMA) guidelines. The risk of bias was assessed using the PEDro scale tool. The review showed a possibly positive impact of polyphenol consumption on recovery after EIMD in team sports athletes. No differences were found between sexes. Considering the limitations, there is moderate to very low certainty of polyphenol supplementation effects on recovery of team sport females and males. A dose of 60 mL/day, divided into two times per day, ingested for >7 days may present positive effects on muscle function and muscle soreness in team sport athletes. However, further investigation is required, specifically in females.


Assuntos
Desempenho Atlético , Mialgia , Atletas , Desempenho Atlético/fisiologia , Proteína C-Reativa/metabolismo , Creatina Quinase/metabolismo , Feminino , Humanos , Masculino , Músculo Esquelético/metabolismo , Mialgia/tratamento farmacológico , Polifenóis/metabolismo , Polifenóis/farmacologia , Polifenóis/uso terapêutico , Esportes de Equipe
9.
PLoS One ; 17(1): e0262276, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35045106

RESUMO

Technical elements are related to shooting performance; however, the importance of each factor regarding performance, especially in elite-level pistol shooters, remains controversial. The objective of this study was to determine the technical factors that influence pistol performance. One elite-level shooter was analysed during the season before the Olympic classification European championship through a total of six competitions (n = 360 shots). Aiming point trajectories were measured with the SCATT optoelectronic system. Variables were classified into six categories: performance; aiming time; stability of hold; aiming accuracy; cleanness of triggering and shooting delta. Principal component analysis, multiple regressions, Pearson correlations and ANOVAs were used to analyse the data. The results showed that five components (aiming time, stability of hold, aiming accuracy, cleanness of triggering and shooting delta) determined a total of 79.68% of the shooting variance. Specifically, aiming accuracy and cleanness of triggering explained up to 25% of the shooting score, with cleanness of triggering serving as the determining factor. Correlations were found among the performance and stability of hold, aiming accuracy, cleanness of triggering and shooting delta. Last, significant differences were found among 8-score, 9-score and 10-score shots. We conclude that while aiming accuracy seems to be related to the performance, cleanness of triggering could be the most critical technical element; furthermore, while stability of hold does not seem to be a determining factor of the score, it could be a general prerequisite to achieve high levels of performance in elite-level air pistol shooters.


Assuntos
Desempenho Atlético/fisiologia , Equilíbrio Postural/fisiologia , Desempenho Psicomotor/fisiologia , Adulto , Armas de Fogo , Humanos , Masculino , Análise de Componente Principal , Análise e Desempenho de Tarefas
10.
J Hum Kinet ; 80: 223-237, 2021 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-34868431

RESUMO

The relative age effect (RAE) is a phenomenon present in team sports, but it does not influence each gender to the same extent. This study aimed to examine the RAE and its relation to performance in international women's handball competitions (2017/18 World Championships). The sample was composed of 1,096 female players distributed into three categories: youth or under 18 (n = 369); junior or under 20 (n = 328) and senior (n = 399). The teams were divided into four groups based on their final position (medalist, quarter-finalist, eight-finalist and bottom-eight teams). The birthdate distribution (trimesters and semesters) was analysed according to the competition category and the playing position. Differences between the expected and observed birthdate distribution were checked using the chi-square statistical test followed by the calculation of the odds ratio. The results revealed, by trimester, the presence of the RAE in the youth (x2(7) = 87.22; p < 0.001) and junior (x2 (7) = 33.12; p < 0.001) categories, with no impact on senior (p > 0.05). The effect size was relatively strong in the youth category (Vc = 0.48). By semester, the prevalence of the RAE was also found in the senior category (p < 0.05). According to the playing position, the RAE was especially detected in 'goalkeeper' (p < 0.01) and 'centre-back' (p < 0.05) positions, both in U-18 and U-20 categories. Surprisingly, this effect also appeared in the 'back' players in the senior category (p < 0.05). A prevalence of the RAE was identified in teams with a higher final position, but interestingly had a greater impact in the quarter-finalist teams (p < 0.001) than in the medalist teams (p < 0.01). The findings demonstrated that the RAE tends to decrease as the chronological age of players increases, demonstrating a strong presence according to collective performance in international women's handball.

11.
Artigo em Inglês | MEDLINE | ID: mdl-33498957

RESUMO

Research in instability has focused on the analysis of muscle activation. The aim of this systematic review was to analyse the effects of unstable devices on speed, strength and muscle power measurements administered in the form of controlled trials to healthy individuals in adulthood. A computerized systematic literature search was performed through electronic databases. According to the criteria for preparing systematic reviews PRISMA, nine studies met the inclusion criteria. The quality of the selected studies was evaluated using STROBE. The average score was 14.3 points, and the highest scores were located in 'Introduction' (100%) and 'Discussion' (80%). There is great heterogeneity in terms of performance variables. However, instability seems to affect these variables negatively. The strength variable was affected to a greater degree, but with intensities near to the 1RM, no differences are observed. As for power, a greater number of repetitions seems to benefit the production of this variable in instability in the upper limb. Instability, in comparison to a stable condition, decreases the parameters of strength, power, and muscular speed in adults. The differences shown are quite significant in most situations although slight decreases can be seen in certain situations.


Assuntos
Força Muscular , Treinamento Resistido , Adulto , Exercício Físico , Humanos , Músculos , Extremidade Superior
12.
Artigo em Inglês | MEDLINE | ID: mdl-34682307

RESUMO

This systematic review aimed to examine the prevalence of the relative age effect (RAE) in swimming and its impact on competition performance according to different types of interacting constraints. A systematic literature search, following the PRISMA guidelines for preparing systematic reviews, was performed through four electronic databases, and nine studies met the inclusion criteria. The quality of the selected studies was evaluated using STROBE, and an average score of 16.2 points was obtained. In these studies, the prevalence of the RAE in swimming was observed in more than half (58.65%) of the participants analysed, and the effect of the RAE was more accentuated in young categories (decreased as age increased and was inverted in older ones) and in male swimmers (double that in female swimmers).The impact of the RAE on competitive performance appeared to be related to the strength demands of the event, as the performance in simultaneous strokes, in shorter events, and of swimmers in the postadolescence period seems to be more affected by the RAE. These results indicate that the RAE in competitive swimming relies on individual and environmental (the swimmer's age group and gender) but also task (the competitive events) determinants or limitations. This should serve as a guide for a more effective design of selection and development procedures for young athletes.


Assuntos
Desempenho Atlético , Natação , Idoso , Atletas , Comportamento Competitivo , Feminino , Humanos , Masculino , Prevalência
13.
Artigo em Inglês | MEDLINE | ID: mdl-35010592

RESUMO

Lower limb injuries are frequent in handball and a serious hindrance to athletic performance. The aim of this systematic review was to synthesize the available research on the prevalence of lower limb injuries in handball players according to sex and competitive level. According to the Preferred Reporting Items for Systematic Reviews and Meta-Analysis, 19 studies were selected after a systematic search and selection process of three digital databases: Scopus, PubMed, and Web of Science. Furthermore, a study quality analysis using an 'Extension for Sports Injury and Illness Surveillance of the Strengthening the Reporting of Observational Studies in Epidemiology (STROBE-SIIS)' was carried out. The sample consisted of 7110 male and female handball players registering 4483 injuries in their lower limbs. The results showed a high incidence of knee injuries (30.23%) and ankle injuries (24.80%), especially in the ligaments, such as the talofibular and the anterior cruciate ligaments. Considering sex and competitive level, knee injuries accounted for 47.02% of injuries among women, while among men, ankle injuries were most prevalent (34.22%) in international competitions. Additionally, the most common cause of injuries was trauma (85.61%). The findings highlighted that the prevalence of lower limb injuries varies greatly according to the characteristics of the sample and injury. Therefore, the study underlines the importance that sports practitioners (physical trainers, readapters, and physiotherapists) adapt training protocols to reduce injury incidence in the most affected body areas or tissues.


Assuntos
Traumatismos em Atletas , Desempenho Atlético , Traumatismos do Joelho , Traumatismos em Atletas/epidemiologia , Feminino , Humanos , Incidência , Extremidade Inferior , Masculino , Prevalência
14.
Front Psychol ; 12: 673434, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34267706

RESUMO

Background: Competitive success is the ultimate objective of elite professional sport organisations. Relative age effects (RAE) impact athlete selection processes in the short and long-term performance. The aims of this study were: (i) examine the presence of RAE by gender, competitive level, and playing position, as well as evaluate the impact of RAE on individual (goals, percentage of effectiveness in shots, saves; percentage of effectiveness in saves, assists, turnovers, steals, blocked shots, penalties, minutes played, and minutes played per match) and collective competition performance (final team position); and (ii) analyse the impact of RAE on the evolutionary trends of individual performance in international competitions throughout 16 seasons in Spanish handball (2005-2020). Methods: The sample included 631 Spanish handball players (male: n = 359; female: n = 272). A Chi-square goodness-of-fit test was used to assess whether a skewed birthdate distribution occurred. A one-way analysis of variance (ANOVA) of independent measures was used to examine the individual and collective statistical parameters by birth quartiles. A linear regression in a Hopkins sheet were performed to compare individual performance trends. Results: The results revealed RAE in the male formative categories (p < 0.001), as well as the male and female senior categories (p < 0.05). By position, RAE especially affected the "centre-back" in the male formative (p < 0.01) and senior categories (p < 0.05). No significant relationship between RAE and individual performance was found in male formative categories, while an impact of RAE on the "minutes played" was detected in the female senior category (p < 0.05). With regard to collective performance, a higher number of relatively older handball players was observed in the best ranked teams in the male formative categories and in the quarter-final teams in the female formative categories (p < 0.05). Among the male players, relatively older players spent more minutes on the court than relatively younger players, although this advantage dissipated over time and did not lead to better performance. Among the female players, relatively younger players were found to perform better as the level of competitive handball increased. Discussion: These findings are important for talent identification and development policies in sport federations and other elite sport institutions by demonstrating the many unintended consequences of selections to international competitions at the youth level.

15.
Nutrients ; 13(3)2021 Mar 06.
Artigo em Inglês | MEDLINE | ID: mdl-33800853

RESUMO

Cognitive functions are essential in any form of exercise. Recently, interest has mounted in addressing the relationship between caffeine intake and cognitive performance during sports practice. This review examines this relationship through a structured search of the databases Medline/PubMed and Web of Science for relevant articles published in English from August 1999 to March 2020. The study followed PRISMA guidelines. Inclusion criteria were defined according to the PICOS model. The identified records reported on randomized cross-over studies in which caffeine intake (as drinks, capsules, energy bars, or gum) was compared to an identical placebo situation. There were no filters on participants' training level, gender, or age. For the systematic review, 13 studies examining the impacts of caffeine on objective measures of cognitive performance or self-reported cognitive performance were selected. Five of these studies were also subjected to meta-analysis. After pooling data in the meta-analysis, the significant impacts of caffeine only emerged on attention, accuracy, and speed. The results of the 13 studies, nevertheless, suggest that the intake of a low/moderate dose of caffeine before and/or during exercise can improve self-reported energy, mood, and cognitive functions, such as attention; it may also improve simple reaction time, choice reaction time, memory, or fatigue, however, this may depend on the research protocols.


Assuntos
Atletas/psicologia , Desempenho Atlético/psicologia , Cafeína/farmacologia , Cognição/efeitos dos fármacos , Substâncias para Melhoria do Desempenho/farmacologia , Adulto , Feminino , Humanos , Masculino , Ensaios Clínicos Controlados Aleatórios como Assunto
16.
Artigo em Inglês | MEDLINE | ID: mdl-34501619

RESUMO

The outbreak of the COVID-19 pandemic and the resulting restrictions designed to slow the spread of infection greatly disrupted people's lives. The present study aimed to investigate the impact of lockdown on the psychology, training, and sleep habits of a cohort of basketball players. An online survey involving 169 professional and amateur athletes was conducted using four validated psychological questionnaires (WLEIS-S, POMS, BRS, SMS-II) and a Likert scale to measure the rating of perceived exertion (RPE) and training variables. Gender differences in fatigue (p = 0.022); friendships (p = 0.017); others' emotional appraisal (p < 0.001); and resilience (p = 0.031) were apparent, with higher values for women in all categories bar resilience. Comparisons before and during the lockdown revealed that all participants reduced their RPE (p < 0.001); training days (p = 0.004); and training hours (p < 0.001), and experienced a decline in the quality of sleep (p < 0.001). Sleep hours (p < 0.001) increased during lockdown. The professionals and females maintained their training days (p > 0.05), while the non-professionals and males did not. Psychological states during lockdown were a predictor of the differences in training and recovery variables. In situations where training and competition are limited, it is important to develop plans to maintain physical activity, good quality sleep, and promote greater emotional management and understanding to control negative moods.


Assuntos
Basquetebol , COVID-19 , Atletas , Controle de Doenças Transmissíveis , Feminino , Hábitos , Humanos , Masculino , Pandemias , SARS-CoV-2
17.
Front Psychol ; 11: 1947, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-33071837

RESUMO

Background: The impact on athletes based on grouping methods according to the date of birth within the constituent year, known as the relative effect of age (RAE), is a factor that can influence the achievement of sports success. Many studies have examined the magnitude of this phenomenon in sport; however, the relationship between the RAE and performance in team sports competition has not been accurately evaluated so far. The purpose of this study was to conduct a systematic review on the influence of the RAE on competition performance in team sports through analysis of published peer-reviewed articles from 2000 to 2019. Methods: According to Preferred Reporting Items for Systematic Reviews and Meta-Analysis systematic search guidelines, 19 studies were identified of the 2,093 that were found in the systematic searching process carried out in four databases: Sport Discus, PubMed, Web of Knowledge, and Scopus. The sample of the study was composed by 77,329 players, of which 92.08% were male and 7.92% were female, whereas the recorded performance measurements were 87,556. The relation between relative age effects and competition performance was registered according to constraints-based theoretical model: individual constraints (sample characteristics) and task constraints (sport context). Moreover, study quality analysis, Strengthening the Reporting of Observational Studies in Epidemiology, was carried out. Results: The short-term individual (10.20%) and collective (18.09%) performance was influenced by the RAE, whereas the long-term individual performance (49.71%) was affected by the RAE reverse. However, in 16.99% of the measurements, no relationship was found between the RAE and competition performance. In the analysis by subcategory, the influence of the RAE was higher in men, in adulthood (senior category), in invasion games, and in national contexts. Discussion: The findings clearly demonstrated that the RAE has a great influence on the performance in team sport. Possible implications for policy and practice should be discussed in order to prevent unequal practice based on biased models that prioritize the athlete's current performance and therefore obviate their maturational development. The heterogeneity and variability of the identified results require a relativization of the findings of this study.

18.
Artigo em Inglês | MEDLINE | ID: mdl-33228103

RESUMO

Performance in basketball is multifactorial. One of the modifying factors is the "Relative Age Effect-RAE". However, its impact depends on the sample characteristics and sport context. The purpose of this study was to examine the influence of the RAE on basketball competition performance by analysing peer-reviewed articles published until July 2020. According to the Preferred Reporting Items for Systematic Reviews and Meta-Analyses systematic search guidelines, nine studies were identified in four databases: Sport Discus, PubMed, Web of Science, and Scopus. Moreover, a study quality analysis using "Strengthening the Reporting of Observational Studies in Epidemiology" guidelines was carried out. The results confirmed an impact of the RAE on competition performance in basketball (56% measurements) and a higher influence of the RAE on short-term collective performance (54% measurements). Statistical parameters were affected, especially in men and U14-U18 categories. No impact of the RAE reversal and no influence of the RAE on long-term collective performance were found. There was a higher impact of the RAE in men (71%), the U14-U18 categories (44%), and at the national level (40%) was identified. The RAE has a variable influence on basketball performance according to developmental constraints. Nevertheless, the findings should be considered based on the sport context due to the heterogeneity and variability of the identified results.


Assuntos
Desempenho Atlético , Basquetebol , Adolescente , Fatores Etários , Desempenho Atlético/estatística & dados numéricos , Basquetebol/estatística & dados numéricos , Feminino , Humanos , Masculino
19.
Artigo em Inglês | MEDLINE | ID: mdl-32326256

RESUMO

Combat sports have a great interest in society and among professional sports. They are an important group of sports in the Olympic Games, but the strategies carried out by athletes to reduce body weight for weighing day, is famously known, suffering the adverse physical and psychological effects of rapid weight loss. This could compromise not only the performance, but the health and development of young athletes. A total of 22 elite male judokas (18.05 ± 1.05 years old) were evaluated during four different competitions in one season; the variables of body weight, water levels, and lean and fat mass were measured by bioimpedance (BIA), (Tanita BC545N) during one season. Using the linear mixed model test, we found significant differences in bodyweight variable during the competitions 3-4. The water level variable showed significant differences in all competitions, except for 2-4. Body mass index was significantly different in all competitions, being higher in the later competitions, except between competitions 1-2 and 2-3. Judokas participate in weight loss methods for their weigh-in days. Furthermore, the age at which the athletes reduced their water levels are worrisome. These results could be used to create healthy programs, especially in elite judokas, in order to carry out strategies before, during, and after competitions with weight loss and controlled water levels increasing future performance and health.


Assuntos
Índice de Massa Corporal , Peso Corporal , Artes Marciais , Adolescente , Adulto , Atletas , Humanos , Masculino , Redução de Peso , Adulto Jovem
20.
Nutrients ; 12(6)2020 Jun 17.
Artigo em Inglês | MEDLINE | ID: mdl-32560317

RESUMO

Endurance can be defined as the capacity to maintain one's velocity or power output for the longest possible time. Maintaining such activity can lead to the onset of fatigue. Dietary nitrate supplementation produces an ergogenic effect due to the improvement of mitochondrial oxygen efficiency through a reduction in the oxygen cost of exercise that increases vasodilation and blood flow to the skeletal muscle in recreationally active subjects. However, the effects of dietary nitrate supplementation on well-trained endurance athletes remain unclear; such supplementation could affect more performance areas. In the present study, a systematic review of the literature was conducted to clarify the use and effects of nitrate as a dietary supplement in endurance athletes trained in cyclic sports (repetitive movement sports). A systematic search was carried out following the Preferred Reporting Items for Systematic Review and Meta-Analyses (PRISMA) guidelines in the databases of SCOPUS, Web of Science (WOS), Medline (PubMed), and Sport Discus from 1 January 2010 to 30 November 2019. Twenty-seven studies were included in the study. The methodological quality of the articles was assessed using the McMaster Critical Review Form. Statistically significant ergogenic results were obtained in 8 (29.63%) of the 27 studies investigated, with significant results obtained for cardiorespiratory parameters and performance measures. Improvement in exercise tolerance was obtained, which could help with exhaustion over time, while the improvement in exercise economics was not as clear. Additionally, the dose necessary for this ergogenic effect seems to have a direct relationship with the physical condition of the athlete. The acute dose is around 6-12.4 mmol/day of nitrate administered 2-3 h before the activity, with the same amount given as a chronic dose over 6-15 days. Further studies are required to understand the factors that affect the potential ergogenic impacts of nitrate on athletic performance among endurance athletes.


Assuntos
Atletas , Suplementos Nutricionais , Nitratos/farmacologia , Substâncias para Melhoria do Desempenho/farmacologia , Resistência Física/efeitos dos fármacos , Humanos
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