Percorrer por autor "Oliveira, Rafael"
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- 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.
- Acute and chronic workload ratios of perceived exertion, global positioning system, and running-based variables between starters and non-starters: a male professional team studyPublication . Nobari, Hadi; Alijanpour, Nader; Martins, Alexandre Duarte; Oliveira, RafaelThe study aim was 2-fold (i) to describe and compare the in-season variations of acute: chronic workload ratio (ACWR) coupled, ACWR uncoupled, and exponentially weighted moving average (EWMA) through session-rated perceived exertion (s-RPE), total distance (TD), high-speed running distance (HSRD), and sprint distance across different periods of a professional soccer season (early, mid, and end-season) between starters and non-starters; (ii) to analyze the relationship the aforementioned measures across different periods of the season for starters and non-starters. Twenty elite soccer players (mean±SD age, 29.4±4.4 y; height, 1.8±0.1m; and body mass, 74.8±2.3kg). They were divided into starter and non-starter groups and were evaluated for 20weeks. ACWR had general changes throughout the season. At the beginning and end of the mid-season, the highest ACWR was observed in three parameters: s-RPE, TD, and HSRD. ACWR and EWMA through sprint distance were higher at the beginning of the early-season than at any other time of the season. The ACWR coupled of s-RPE shows a significant higher value for non-starters than starters (p=0.015; g=−1.01 [−1.98, −0.09]) and the ACWR coupled of TD shows a significant higher value for starters than non-starters in early-season (p<0.01; g=3.01 [1.78, 4.46]) and shows a significant higher value for non-starters than starters in mid-season (p<0.01; g=−2.52 [−3.83, −1.39]), and end-season (p<0.01; g=−2.57 [−3.89, −1.43]). While the EWMA of TD shows a significant higher value for starters than non-starters in early season (p<0.01; g=2.25 [1.17, 3.49]) and mid-season (p<0.01; g=2.42 [1.31, 3.71]), and shows a significant higher value for non-starters than starters in end-season (p<0.01; g=−2.23 [−3.47, −1.16]). Additionally, we found some correlations between external and internal load measures during three periods of the in-season. The study’s main finding was that the indexes of ACWR and EWMA were useful to detect differences between period and between playing status with the exception for the sprint variable. In addition, the necessary work for non-starter players’ improvement is not done during training, and these players lose their readiness as the season progresses. Consequently, these players perform poorly during the match. Therefore, coaches and their staff should consider devising new activities to keep non-starter players physically fit. This deficit must be accounted for in training because they compete in fewer matches and have less burden than starters.
- 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.
- Acute: chronic workload ratio and training monotony variations over the season in professional soccer: a systematic reviewPublication . Rico-González, Markel; González Fernández, Francisco Tomás; Oliveira, Rafael; Clemente, Filipe ManuelAcute: chronic workload ratio (ACWR) and training monotony have been criticized as injury risk predictors. Therefore, the use of intensity measures should be oriented to understand the variations of intensity across the season. The aim of this systematic review is to summarize the main evidence about the ACWR and training monotony variations over the season in professional soccer players. The search was made in PubMed, SPORTDiscus, and FECYT according to the Preferred Reporting Items for Systematic Reviews and Meta-Analyses guidelines. From the 225 studies initially identified, 27 were fully reviewed, and their outcome measures were extracted and analyzed. Existing literature revealed a variety of designs, ACWR and training monotony ranges, variables assessed and durations of the studies. Overall, the range values for ACWR were 0.4–3.39 AU, while those focused on monotony were 0.49–5.7 AU. Regarding ACWR, the ratios located around 0.85–1.25 could predict lower risk values and ratios around ≥1.50 could predict higher risk values. On the contrary, with respect to training monotony, the ratios are approximately between 0.5 and 2.00 (low values in the preseason and low competition weeks and high values when soccer players are in highly scheduled competition weeks). Nevertheless, ACWR and training monotony methods should be addressed and considered based on their real value before using this indicator to reduce injury risk. In fact, the data did not conclusively define injured and non-injured players. For this reason, utilizing standardized approaches will allow for more precise conclusions about professional soccer players.
- Acute:chronic workload ratio and training monotony variations over the season in youth soccer players: A systematic reviewPublication . Rico-González, Markel; Oliveira, Rafael; González Fernández, Francisco Tomás; Clemente, Filipe ManuelSince acute:chronic workload ratio and training monotony have been criticized as injury risk predictors, the use of inten sity measures should be more oriented to understand the variations of intensity across the season. The aim of this sys tematic review is to summarize the main evidence about the acute:chronic workload ratio and training monotony variations over the season in youth soccer players. The search was made in PubMed, SPORTDiscus, and FECYT (Web of Sciences, CCC, DIIDW, KJD, MEDLINE, RSCI, and SCIELO) according to Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines. From the 225 studies initially identified, 13 were fully reviewed, and their outcome measures were extracted and analyzed. Nine analyzed acute:chronic workload ratio, seven analyzed mon otony, and four studies analyzed both acute:chronic workload ratio and monotony. Overall, the range values for acute: chronic workload ratio were 0.58–17.5 AU, while for monotony were 0.83–23.0 AU which showed a higher variability. Few studies showed an association between higher values of acute:chronic workload ratio and/monotony with injury risk or to prevent health problems. These measures could be used to understand the variations of the data through the in season periods. However, caution is necessary due to the scarce studies performed in young soccer players.
- Adaptações fisiológicas ao esforço na gravidez e pós-partoPublication . Brito, João; Oliveira, RafaelA gravidez (gestação) é vista como um fenómeno fisiológico, embora tivesse existido um processo histórico baseado nos sinais e sintomas da gestação que pudesse indicar alguma doença. Apesar disso considera-se a condição fisiológica normal do período gestacional (Ferreira & Nakano, 2001). As adaptações sofridas pela gestante destinam-se a fornecer necessidades de homeostasia e crescimento fetal, sem um comprometimento do bem-estar materno. Sendo assim, todas as transformações que ocorrem na grávida são fisiológicas e não patológicas, produzindo na gestante a capacidade de nutrição e proteção aumentadas para o bebé, aumentando a eficácia das funções corporais (Barron & Lindheimer 1996; Hacker & Moore, 1994). Durante a gestação, o corpo da grávida passa por uma série de adaptações que envolvem vários aparelhos e sistemas, tais como, respiratório, cardíaco, hormonal, ósseo e muscular. Essas alterações são de nível fisiológico e também mecânico. Desse modo, torna-se importante compreender essas alterações para que os profissionais de saúde e do desporto possam intervir proporcionando uma melhoria, bem-estar e qualidade de vida às gestantes (Almeida et al. 2005).
- An analysis of positional generic and individualized speed thresholds within the most demanding phases of match play in the english premier leaguePublication . Kavanagh, Ronan; McDaid, Kevin; Rhodes, David; McDonnell, Jack; Oliveira, Rafael; Morgans, RylandTo analyze the positional distances covered above generic and individualized speed thresholds within the most demanding phases of match play. Categorized by position, 17 English Premier League players’ match data were analyzed over 2 consecutive seasons (2019–20 and 2020–21). The most demanding phases of play were determined using a rolling average across 4 periods of 1, 3, 5, and 10 minutes. Distance covered in the time above the standard speed of 5.5 m/s was analyzed, with individualized metrics based on the maximal aerobic speed (MAS) test data. Results: Central defenders displayed lower values for high-intensity periods when compared with fullbacks, midfielders, and wide midfielders for both generic and individualized metrics. MAS during 1-minute periods was significantly higher for forwards when compared with central defenders (82.9 [18.9] vs 67.5 [14.8] for maximum high-speed running [HSR] and 96.0 [15.9] vs 75.7 [13.8] HSR for maximum MAS activity). The maximum effect size differences between the central midfielders, wide midfielders, and fullbacks for HSR and MAS measures under the maximum HSR criterion was 0.28 and 0.18 for the 1-minute period, 0.36 and 0.19 for the 3-minute period, 0.46 and 0.31 for the 5-minute period, and 0.49 and 0.315 for the 10-minute period. Conclusions: Individualized speed metrics may provide a more precise and comparable measure than generic values. Data appear to be consistent across playing positions except for central defenders. This information may allow practitioners to directly compare individualized physical outputs of non–central defenders during the most demanding phases of play regardless of the players’ positional group. This may provide coaches with important information regarding session design, training load, and fatigue monitoring.
- 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.