Percorrer por tipo de recurso "research article"
A mostrar 1 - 10 de 30
Resultados por página
Opções de ordenação
- Active and sham transcranial direct-current stimulation (tDCS) plus core stability on the knee kinematic and performance of the lower limb of the soccer players with dynamic knee valgus; two armed randomized clinical trialPublication . Samakosh, H.M.N; Maktoubian, M.; Doost, S.P.R.; Oliveira, Rafael; Badicu, G.; Al-Mhanna, S.B.; Hassanzadeh, M.; Amadekhiar, P.; Vaskasi, R.R.; Oliveira, RafaelDynamic knee valgus (DKV) is a prevalent risk factor for anterior cruciate ligament (ACL) injuries in soccer players, particularly during noncontact mechanisms. Transcranial direct-current stimulation (tDCS) and core stability exercises have shown promise in enhancing motor control and biomechanical alignment, but their combined effects on DKV remain unexplored. This study aimed to evaluate the efficacy of active versus sham tDCS combined with core stability exercises on knee kinematic alignment and lower limb performance in young male soccer players with DKV. In this double-blind, randomized controlled trial, 42 male soccer players (aged 18–25 years) with DKV were randomly assigned to either an active tDCS group (n = 21) or a sham tDCS group (n = 21). Both groups underwent 8 weeks of core stability exercises (3 sessions/week, 30 minutes/session) preceded by 15 minutes of active (2 mA) or sham tDCS targeting the primary motor cortex (M1). The primary outcome was the frontal plane projection angle (FPPA) during a single-leg landing task, measured using 2D video analysis. Secondary outcomes included vertical jump height and 8-hop test time. Outcomes were assessed at baseline and post-intervention. A 2 × 2 mixed-model ANOVA with Bonferroni-corrected post hoc tests was used for statistical analysis via SPSS27. The active tDCS group showed significantly greater improvements in FPPA (+5.65% vs. +2.26%, p < 0.001, 𝜂p² = 0.82), vertical jump height (+25.30% vs. +10.45%, p < 0.001, 𝜂p² = 0.75), and 8-hop test time (−21.05% vs. −14.27%, p < 0.001, � �p² = 0.68) compared to the sham group. Both groups improved from baseline, but the active tDCS group exhibited larger effect sizes across all outcomes. Active tDCS combined with core stability exercises significantly enhanced knee kinematic alignment and lower limb performance in soccer players with DKV compared to sham tDCS. These findings suggest that neuromodulation, when paired with targeted exercise, is a promising strategy for injury prevention and performance enhancement in athletes. Further research is needed to explore long-term effects and applicability to diverse populations.
- The acute effect of foam roller application on eccentric knee flexor strength in rugby sevens players: a randomised crossover trialPublication . Sağıroğlu, Isa; Ceylan, Halil İbrahim; Özdemir, Kübra; Oliveira, Rafael; Morgans, Ryland; Bragazzi, Nicola Luigi; ceylan, halil ibrahimBackground: Hamstring injuries account for approximately one in six injuries for rugby players. Contributing factors include poor eccentric strength and reduced range of motion (ROM) at the hip and knee joints. Beyond specific training methods, foam rolling is employed extensively to enhance ROM, joint mobility, general performance, and other outcomes pre- and post-physical exercise. The study aimed to investigate the acute effect of foam roller application on eccentric knee flexor strength, hip, and knee ROM in rugby sevens players. Methods: A total of 23 rugby sevens players (age: 24.16 ± 2.15 years, height: 177.0 ± 5.89 cm, body mass: 64.57 ± 6.65 kg) underwent two conditions in a randomised crossover experiment. The experimental condition included Foam Roller (FR) exercises (3 sets, 30 seconds each with 10-second recovery intervals) on the gastrocnemius and hamstring muscles of both limbs. The non-foam rolling (NFR) condition involved resting on the mat for the same time period as the foam rolling session. Maximal eccentric strength (MES), average eccentric strength (of three repetitions) (AES), active straight leg raise (ASLR), and active knee extension (AKE) tests were performed on both limbs pre- and post- each condition. Results: The present study revealed that FR improved MES and AES (~1.4–1.7%, p < 0.001), ASLR (~9–10%, p < 0.001), and AKE (~8–10%, p < 0.001) compared to the NFR condition. Conclusions: These findings confirm that FR is a viable strategy to improve eccentric knee flexor strength, hip, and knee ROM before other activities. Such applications may be useful in improving performance and reducing injury risk for athletes.
- Acute skin temperature responses to the 30-15 intermittent fitness test in professional male soccer playersPublication . Sümer Alvurdu; Arslan, Yasin; Keskin, Kadir; Oliveira, Rafael; Nobari, HadiIntroduction: Thermal imaging technology provides detailed insights into the skin temperature patterns and asymmetries of athletes, offering valuable data to enhance performance, assess the effectiveness of rehabilitation, monitor fatigue, and prevent injuries. Methods: The aim of this study was to assess acute skin temperature responses before and after the 30-15 Intermittent Fitness Test in professional male soccer players. Twenty-one profes sional soccer players performed a 30-15 IFT, and the running time, peak velocity, and true ve locity were calculated. Thermal images of the players were acquired using an infrared thermal camera before and immediately after the 30-15 IFT, and skin temperature measurements were analyzed from the anterior thigh, anterior leg, posterior thigh, and posterior leg. Results: The skin temperature asymmetries differed significantly between all regions of inter est, with the greatest difference in the anterior and posterior thighs. Pearson correlation anal ysis revealed that the 30-15 IFT parameters were not correlated with the posttest skin temper ature asymmetry for any of the region of interests. However, there were significant negative correlations between pretest skin temperature asymmetry in the posterior leg region and all 30-15 IFT parameters for running time (r=0.30; p<.05), peak velocity (r=0.3; p<.05), and true velocity (r=0.25; p<.05). Finally, athletes with lower baseline skin temperature asymmetries in the posterior leg region have better 30-15 IFT performance. Conclusion: Thermal imaging can be used to assess muscular asymmetries following specific endurance tests or conditioning training, and this information can provide valuable information for optimizing performance and injury prevention.
- Análise da composição corporal, competência motora e saúde mental no risco de lesão em atletas de formação de futebol e futsalPublication . Tavares, Bárbara; Mercê, Cristiana; Santos, Fernando Jorge Lourenço; Oliveira, RafaelA prática desportiva, particularmente no âmbito da formação de jovens atletas, é essencial para o seu desenvolvimento integral, abrangendo as dimensões físicas, psicológicas e sociais. Este estudo teve como objetivo avaliar diferenças entre atletas de futebol e futsal, considerando variáveis antropométricas, motoras e psicológicas, bem como explorar possíveis correlações entre estas dimensões. Participaram 228 atletas masculinos e femininos de ambas as modalidades, sendo utilizados instrumentos como a bateria Motor Competence Assessment (MCA) para avaliação da competência motora, o Inquérito de Morbidade Referida (IMR) para levantamento de lesões, e o Questionário das Características Psicológicas Relacionadas com o Rendimento Desportivo (CPRD) para análise de variáveis psicológicas. Igualmente foi avaliada a composição corporal através do peso e altura. Os resultados demonstraram que os atletas de futebol apresentaram maior incidência de lesões em comparação com os de futsal (p = 0,014), enquanto o desempenho motor foi significativamente superior no futebol em testes como os saltos laterais, horizontais e shuttle run (p < 0,001). Além disso, ambas as modalidades obtiveram percentis máximos nos testes de atirar e pontapear, refletindo a influência da especificidade das modalidades. As características psicológicas apresentaram relações limitadas com a competência motora, sendo observadas apenas algumas correlações no futebol feminino. Conclui-se que as especificidades das modalidades influenciam diretamente as competências motoras e as incidências de lesões, sublinhando a necessidade de estratégias de treino personalizadas e integradas para otimizar o desempenho e prevenir lesões em cada contexto desportivo.
- Análise da variação da carga Interna de treino ao longo de dez microciclos dos períodos preparatório e competitivo numa equipa europeia de futebol jovemPublication . Oliveira, Rafael; Fernandes, Renato; Dinis, Miguel; Ferreira, Francisco; Brito, João PauloO presente estudo comparou a carga semanal de treino interno em 10 microciclos (M) em atletas sub-12. Vinte e oito jogadores de futebol sub-12 (idade, 10,96 ± 0,19 anos, altura, 152,82 ± 7,47 cm, peso 40,76 ± 6,29 kg) participaram no estudo. A carga de treino interno foi quantificada através da perceção subjetiva de esforço da sessão. Foram calculadas a carga semanal média, a carga semanal acumulada, a monotonia e tensão do treino para cada M (1 a 5 do período preparatório e 6 a 10 do período competitivo). Os resultados revelaram diferenças significativas considerando todas as métricas (p < 0,001 para todas). Especificamente, a carga semanal média foi menor nos M4 e M7, enquanto a carga semanal acumulada foi menor nos M1, M2 e M9. A monotonia do treino e o esforço do treino apresentaram os valores mais baixos (p < 0,001 para todos) nos M1 e M9 (0 unidades arbitrárias) e os mais elevados no M6. Os dados revelaram variações de carga com todas as métricas analisadas. No entanto, as principais diferenças foram encontradas entre os microciclos com menor número de sessões de treino (uma ou duas) e os restantes microciclos, o que revela uma manutenção geral da carga ao longo dos períodos preparatório e competitivo. No entanto, este parece ser o primeiro estudo realizado com atletas sub-12, fornecendo dados relevantes para os treinadores e as suas equipas técnicas.
- Analysis of Internal Training Load Variation Over Ten Microcycles of the Preparatory and Competitive Periods in a European Youth Football TeamPublication . Oliveira, Rafael; Fernandes, Renato; da Costa Dinis, Miguel; Ferreira, Francisco; Brito, João PauloThe current study compared weekly internal training load across 10 microcycles (M) in under-12 athletes. Twenty-eight under-12 soccer players (age, 10.96 ± 0.19 years; height, 152.82 ± 7.47 cm; weight, 40.76 ± 6.29 kg) participated in the study. Internal training load was quantified using session Rating of Perceived Exertion. The average weekly load, accumulated weekly load, monotony and training strain were calculated for each M (1 to 5 of the preparatory period and 6 to 10 of the competitive period). Results revealed significant differences considering all metrics (all, p < .001). Specifically, the average weekly load was lower in M4 and M7, while the accumulated weekly load was lower in M1, M2 and M9. Training monotony and training strain showed lower values (all, p < .001) in M1 and M9 (0 arbitrary units) and the highest on M6. The data revealed load variations with all metrics analysed. However, the main differences were found between the microcycles with the lowest number of training sessions (one or two) and the remaining microcycles, which reveals a general maintenance of the load throughout the preparatory and competitive periods. However, this appears to be the first study carried out with under-12 athletes, providing relevant data for coaches and their technical staff.
- Comparison of external load during differing microcycle structures across two competitive seasons in elite female portuguese soccer playersPublication . Espada, Mário C.; Santos, Fernando J.; Nalha, Matilde; Zmijewski, Piotr; Morgans, Ryland; Oliveira, Rafael; Brito, João Paulo; FERNANDES, RENATOThis study aimed to: (i) compare the accumulated load between three and four training sessions per week plus a match across two consecutive seasons in elite female soccer players, and (ii) compare the training/match ratio (TMr) of external load. Data from 10 players in each season were analysed during the study period. The microcycle structure of the first season included three training sessions (3dW) and a match per week, while the second season included four training sessions (4dW) plus a match per week. The following measures were used for analysis: duration, total distance, high-speed running distance (HSR,>15 km/h), number of accelerations (ACC,>1–2 m.s−2 [ACC1];>2–3 m.s−2 [ACC2];>3 4 m.s−2 [ACC3];>4m.s−2 [ACC4]) and decelerations (DEC,<1–2m.s−2 [DEC1]; <2–3 m.s−2 [DEC2];< 3–4 m.s−2 [DEC3];< 4m.s−2 [DEC4]). The accumulated load was calculated by summing key metrics for all training sessions and matches, while TMr was calculated by dividing the accumulated load by match data. The main results showed that all variables showed meaningful differences (p<0.05) except for ACC4 and DEC4. Specifically, total distance was higher in 3dW than 4dW (p=0.007), while the remaining variables were higher during 4dW. Moreover, all TMr were higher in 4dW than 3dW (p<0.001 for all variables except for ACC4 and DEC4). As expected, this study showed that adding one training session per week increased accumulated load and TMr for several key variables.
- Comparisons of running and accelerometry based measures between playing positions in touch rugby. A case study of an amateur male teamPublication . Oliveira, Rafael; Nalha, MatildeBackground: The main objective of the present study was to quantify the external load of the games that belong to a national tournament by comparing playing positions. A secondary objective consisted in comparing the match-to-match variations. Methods: Fourteen players (four links, four middles and six wings) were included (age: 39.36 ±5.83 years; body mass index: 26.65 ± 4.13). Participants were monitored during a tournament. ThroughGpexepro2, thefollowingmeasureswerecollectedandrelativized per minute: total distance, forward distance, backward distance, zone 1 (0–1.50 m/s), zone 2 (1.50–3.00 m/s), zone 3 (3.00–4.00 m/s), zone 4 (4.00–5.50 m/s), zone 5 (5.50 7.00 m/s)andzone6(>7.00m/s),thenumberofaccelerationsanddecelerations, impacts and jumps. The absolute values of maximal speed, maximal acceleration speed and maximal deceleration speed were also used for analysis. Results: The main findings showed meaningful higher values of zone 4 (16.18 ± 1.89 vs. 5.56 ± 3.53), zone 5 (2.91 ± 0.81 vs. 0.38 ± 0.38), zone 6 (0.35 ± 0.24 vs. 0.00 ± 0.00), deceleration (0.56 ± 0.21 vs. 0.19 ± 0.12), maximal speed (23.56 ± 1.90 vs. 18.84 ± 1.24) and forward distance (102.20 ± 13.45 vs. 67.42 ± 17.40) for middles than wings (p < 0.05), with large to very large effect sizes. In addition, no differences were found when comparing external load data from all matches. Conclusions: The findings of this study showed a clear tendency of higher values for middles than links and wings which provides a deeper understanding of the positional activity profile of an Amateur Portuguese team allowing practitioners to adjust training with the common external load experienced in a tournament. Moreover, the analysis of match-to-match comparison revealed no differences through the competition day, which means a proper fatigue management.
- Contextual analysis of physical-tactical match performance Contextual analysis of physical-tactical match performance demands in elite U21 soccer playersPublication . Craig Davies; Vassallo, Christian; Ryan, Ben; Zmijewski, Piotr; Oliveira, Rafael; Teixeira, José Eduardo; Moreira, Alexandre; Morgans, RylandBackground: Soccer matches include physical and tactical factors, yet limited research has integrated physical-tactical variables involving U21 soccer players. This study examined how different phases of play influence physical intensity in elite U21 soccer players. Materials and Methods: Twelve professional development league matches involving 29 male U21 soccer players (106 obser vations) were analysed. Players wore 10 Hz GPS units to derive relative (m/min) physical metrics during six phases of play. Phases and positions were compared using repeated‑measures ANOVA and one‑way ANOVA. Results: Players covered significantly greater high-speed running per mi nute (HSR/min) during the final third compared to build-up (p = 0.015, ES: 0.5, small) and progres sion phases (p = < 0.001, ES: 0.6, moderate). Furthermore, players covered significantly greater HSR/min during the defensive low block phase compared to build-up (p = 0.001, ES: 0.7, moderate), progression (p = < 0.001, ES: 0.9, moderate), middle block (p = 0.011, ES: 0.7, moderate) and high press (p = 0.001, ES: 0.8, moderate) phases. Conclusions: Differing phases of play required specific physical qualities depending on the position and the tactical role within the team. This integrated approach provides contextualisation of important physical metrics relevant to tactical actions that may inform training design and rehabilitation sessions.
- Correlating diurnal variations in peak athleticism with buccalgene expression in youth football playersPublication . Thomas, A.; Wheeler, J.; Bishop, R.; Prato, M.F.G.; Karakuş, O.; Cain, E.; Kana-Ah, A.; Nisbet, D.; Morgans, Ryland; Oliveira, RafaelHourly variations in athletic performance are a well-documentedphysiological phenomenon in individual and team sports includingfootball. Measuring the timing of maximal performance couldpotentially improve performance. Evidence suggests that buccalgene expression correlates with athletic performance, yet this hasnot been studied in sport-specific participants. Therefore, the studyaimed to (A) examine the expression of Per2 and Bmal1 genes in 45youth football players and correlate with countermovement jump(CMJ) performance; (B) investigate the fluctuations in Per2 andBmal1 expression levels and CMJ performance at various timepointsduring a regular training day. CMJ metrics (Reactive Strength Index-Modified, Force at Peak Power, Eccentric Duration, and Peak Power)and gene expression levels were measured in 45 youth footballplayers at 08:30 and 17:30. Exercise timing made a significant dif-ference in each measured performance metric at the individual andsquad level. Thirty-four participants displayed increases in RSI-mod(p < 0.001) over the morning measurements. This contributed to an8% increase in overall squad performance (p = 0.0009), which sig-nificantly correlated to buccal gene expression (R2 = 0.94). Profilingplayer buccal gene expression could inform the timing of trainingand rehabilitation protocols to coincide with maximal athletic per-formance in football, other team sports, and individual sports.
- «
- 1 (current)
- 2
- 3
- »