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- Change in spatiotemporal parameters during running at different degrees of inclination: systematic reviewPublication . Marszałek, Patryk; Przednowek, Krzysztof; França, Cíntia; Martinho, Diogo V.; Marques, Adilson; Ferrari, Gerson; Paśko, Wojciech; Gouveia, Élvio Rúbio; França, Cíntia; Martinho, Diogo; Marques, Adilson; Gouveia, Élvio RúbioBackground:Running is one of the simplest and most popular forms of exercise. Biomechanical evaluation of running is one of the elements of evaluating running technique and, consequently, improving sports performance. Running uphill and downhill is one of the components of daily running but also an element of training used by recreational runners. The aim of this study is to optimize running training and minimize the risk of injury by identifying changes in the spatiotemporal structure of running at different inclinations. Methods: The Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines were followed. The protocol has been registered on the international platform INPLASY under the number INPLASY202430094U2. The search was conducted up to 30 March 2024 using the Scopus, PubMed, and Web of Science databases. Results: Spatiotemporal parameters were most frequently analyzed at 2.8–3.35 m/s velocities and inclinations in the range of −11% to 11%. Decreases in stride length (SL) and flight time (FT), and increases in step frequency (SF) were the most frequently reported changes from all parameters analyzed as a function of inclination and velocity. Significant increases or decreases in individual parameters were more often observed for positive inclination values than negative ones. Conclusions: The heterogeneous results of the study limit the possibility of determining the changes that occur in the spatiotemporal structure of the run under the impact of different inclinations. The variation in the results for negative inclination values indicates the different characteristics of running uphill and downhill. However, for uphill running, SF, SL, and FT are closely related to the increase in inclination.
- Analyzing the effects of competitive fatigue on body composition and functional capacities of youth elite handball playersPublication . Martins, Francisco; França, Cíntia; Sarmento, Hugo; Przednowek, Krzysztof; Śliż, Maciej; Campos, Pedro; Lopes, Helder; Marques, Adilson; Gouveia, Élvio Rúbio; Pestana Martins, João Francisco; França, Cíntia; Sarmento, Hugo; Pereira Campos, Pedro Filipe; Lopes, Helder; Marques, Adilson; Gouveia, Élvio RúbioHandball demands intense movements like rapid direction changes and physical contact. Consecutive competitions expose player fatigue and weaknesses due to the sport’s exhaustive nature. Therefore, the aims of this study are twofold: (i) to investigate the impact of competitive fatigue on the body composition of youth elite handball players, and (ii) to analyze the impact of concentrated competition on their functional capacity performance. Seventeen young male handball players (age: 16.2 years, height; 177.8 cm, body mass: 73.0 kg) were assessed twenty-four hours before (TM1) and after the competitive period (TM2) in body composition, static strength, lower- and upper-body explosive strength, speed, agility, balance, and flexibility indicators. A Wilcoxon Signed Rank Test was conducted to assess differences in body composition and functional capacities assessment between TM1 and TM2. Regarding results, body mass significantly increased in TM2 (p < 0.01), while increases in waist circumference and body fat percentage were not statistically significant. Functional capacity assessments revealed a significant decline in jumping performance (CMJ and SJ; p ≤ 0.01). Speed and agility assessments showed worse performance in TM2, significantly increasing 30 m sprint time (p ≤ 0.01). Balance indicators showed no significant differences, with mixed results in performance across different conditions. In sum, evaluating vertical jumps and long-distance maximum speed (i.e., 30 meters) could be valid tests for measuring and controlling fatigue in young elite handball players. Future research should regularly monitor young handballers after the competition to analyze the entire fatigue recovery process.
- Variations in locomotor intensities across soccer match halves concerning player sectorial positionsPublication . Gouveia, Élvio Rubio; França, Cíntia; Henriques, Ricardo; Santos, Francisco; Mâncio, Rui; Przednowek, Krzysztof; Sarmento, Hugo; Gouveia, Élvio Rúbio; França, Cíntia; Baeta Santos, Francisco José; Sarmento, HugoPurposeThis study aims to explore disparities in locomotor metrics such as total distance (TD), high-speed running (HSR), accelerations (Acc), decelerations (Dec), and maximum speed (MS) across five soccer positions – centre defenders, fullbacks, midfielders, wingers, and forwards – during the 1-, 3-, and 5-minute match intensity periods (MIP). Additionally, it seeks to assess the difference in those locomotor metrics between the first and second halves of the match.MethodsAn observational, retrospective cohort study was undertaken with a professional team covering 32 official matches. A total of 20 soccer players participated in this study. Data were collected using a 10-Hz GNSS unit (Apex pro series, StatSports, Northern Ireland). The MIP considered different time durations (1, 3, 5 min in the 1st and the 2nd halves).ResultsSoccer players exhibited position-specific differences in locomotion, with Wingers covering the most distance and forwards showing the highest Acc and Dec. HSR was most notable in the fullbacks. The second half saw varied changes, with midfielders increasing in distance covered. ANCOVA revealed significant positional differences in TD during longer MIPs and between match halves. HSR varied across positions but only differed between halves in the 5-minute MIP. Acc and Dec displayed half-time differences, while maximal speed was consistently higher in the second half.ConclusionsThis study highlights the impact of player position and matches progression on locomotor metrics in soccer, underscoring the need for customised training and strategic adaptability to maximise performance throughout the game.
- Lower-body power, body composition, speed, and agility performance among youth soccer playersPublication . França, Cíntia; Gouveia, Élvio; Martins, Francisco; Ihle, Andreas; Henriques, Ricardo; Marques, Adilson; Sarmento, Hugo; Przednowek, Krzysztof; Lopes, Helder; França, Cíntia; Gouveia, Élvio Rúbio; Pestana Martins, João Francisco; Ihle, Andreas; Marques, Adilson; Sarmento, Hugo; Lopes, HelderSpeed and agility have been described as crucial abilities for soccer players. The purpose of this study was to analyze, in detail, the variance in speed and agility tasks explained by lower-body power after controlling for age and body composition. The participants were 96 male soccer players aged 16.1 ± 1.6 years. Body composition (stature, body fat percentage—BF%, body mass, and fat-free mass—FFM), lower-body power (countermovement jump—CMJ, and squat jump—SJ), speed (5-, 10-, and 35 m sprints), and agility (t-test) were assessed. Among body composition parameters, BF% presented the highest number of significant relationships with speed and agility, with the strength of correlations ranging from small (5 m sprint, r = 0.25) to large (35 m sprint, r = 0.52). The strongest correlation coefficient emerged between FFM and the 35 m sprint (r = −0.65). Significant correlations were found between vertical jump performance and the 35 m sprint (CMJ: r = −0.68; SJ: r = −0.69), followed by the t-test (CMJ: r = −0.35; SJ: r = −0.47). The hierarchical multiple regression model could explain 22% to 67% of the variance observed in agility scores and speed. BF% remained the most statistically significant negative predictor of all regression models. The CMJ remained a statistically significant positive predictor of the 35 m sprint (β = −0.581, p ≤ 0.01) after controlling for age and body composition. Integrating programs targeting lower-body power might be important to enhance speed and agility performance in youth soccer. On the other hand, future research based on multidisciplinary approaches to investigate the effects of nutritional strategies in reducing or preventing gains in BF% is still needed, which remained a significant predictor of sprint and agility performance in the final models.
- Knee and hip muscle strength of male soccer players from different competitive levelsPublication . França, Cíntia; Martins, Francisco; Przednowek, Krzysztof; Marques, Adilson; Ihle, Andreas; Sarmento, Hugo; Gouveia, Élvio Rúbio; França, Cíntia; Pestana Martins, João Francisco; Marques, Adilson; Ihle, Andreas; Sarmento, Hugo; Gouveia, Élvio RúbioIn soccer, knee and hip muscle strength assessments have been recommended for injury prevention. The aims of this study were threefold: (1) to compare knee and hip muscle strength between professional players competing at different levels; (2) to compare strength performance according to the preferred leg (PL) and the non-preferred leg (NPL); and (3) to compare knee and hip muscle strength performance at two moments of the season. This study included 33 professional soccer players: 13 were in the elite group (EG), and 20 were in the sub-elite group (SEG). Body composition, isokinetic knee strength at 60º/s, and hip adduction strength were assessed at two different moments (M1 and M2). Values of peak torque (PT), peak torque/bodyweight (PT/BW), and the hamstring-to-quadriceps strength ratio (H:Q) for knee extensors (KEs) and knee flexors (KFs) for both legs were used for analysis. The statistical analysis included the Mann-Whitney U and the Wilcoxon Signed Rank tests. At M1, the EG presented a significantly better performance in KF PT/BW and in the squeeze strength test for the PL and the NPL (p 0.01). At M2, the EG performed substantially better in KE PT/BW and KF PT/BW (p 0.01). No substantial strength differences were observed in knee and hip muscle performance between the PL and the NPL. From M1 to M2, significant increases were found in knee strength in both groups (p 0.01). Overall, the EG players outperformed significantly their lower-division peers in strength assessments. The results indicate significant knee and hip muscle strength increases during the season, probably as a response to the exposure to training and competition.
- Estimated energy expenditure in youth while playing active video games: a systematic reviewPublication . França, Cíntia; Ashraf, Sadaf; Santos, Francisco; Dionísio, Mara; Ihle, Andreas; Marques, Adilson; Nascimento, Marcelo de Maio; Gouveia, Élvio Rúbio; França, Cíntia; Dionisio, Mara; Marques, Adilson; de Maio Nascimento, Marcelo; Gouveia, Élvio Rúbio; Baeta Santos, Francisco JoséSedentary behavior and inadequate energy expenditure are serious global public health concerns among youngsters. The exponential growth in technology emerges as a valuable opportunity to foster physical activity, particularly through active video games. We performed a systematic review following the Preferred Reporting Items for Systematic Reviews and Meta-Analyses guidelines in PubMed, Web of Science, Cochrane, and Scopus to provide a comprehensive view of the literature on energy expenditure levels among adolescents while playing active video games. Among the 574 manuscripts identified at the first screening stage, 23 were retained for analysis. Ten studies were characterized by longitudinal and thirteen by cross-sectional designs. The results showed that short-term active video games elicited energy expenditure values comparable to moderate-intensity physical activity (3–6 METs). However, in intervention programs (with at least six weeks) the results indicate no significant effects of active video games on youngsters’ energy expenditure levels and physical activity profiles between baseline and follow-up assessments. Overall, active video games based on sports and dance were the most used, and boys tended to achieve higher energy expenditure than girls. The diversity of methods implemented limits comparing results and drawing generalized conclusions. However, considering its attractiveness to youth, active video games might emerge as a complementary tool to traditional physical activities promoted in schools and local communities. Details regarding gender differences and contradictory results of longitudinal approaches should be considered in future research based on standardized methods.
- Systematization of the types of adaptations requested in pedestrian routes: human strategies in sport, tourism and other critical situationsPublication . Fernando, Catarina; Fernando, Catarina; Lopes, Hélder; Lopes, Helder; Prudente, João; Prudente, João Filipe; Vicente, AntónioThe aim of this work is to create a structure of knowledge that allows to understand and explain different adaptations requested in pedestrian routes to individuals. We establish the conceptual framework in which this study fits and define its application to two types of frequent adaptations in these activities: uneven terrain and sloped terrain (downhill), establishing which variables to consider and how they interrelate in order to establish decision trees that allow us to make choices and set up strategies consciously and intentionally. We also try to highlight some particularities in the application of these instruments to situations in the field of sport and tourism.
- Evolution of attack in handball when playing 7 vs. 6 with empty goal between 2020 and 2023: coaches’ perception vs. observational resultsPublication . Prudente, João Nunes; Cardoso, Américo Ramos; Rodrigues, Ana José; Mendes, João N.; Fernando, Catarina; Lopes, Hélder; Trejo-Silva, Alejandro; Sousa, Duarte Filipe; Prudente, João Filipe; Ramos Cardoso, Américo; Rodrigues, Ana; Noite Mendes, Joao Manuel; Fernando, Catarina; Lopes, Helder; Sousa, DuarteRecently, several studies on the 7 vs. 6 “empty goal” (EG) in handball have produced different and even contradictory results. The aim of the present study was to investigate the behavior of teams and players in the 7 vs. 6 EG attack in the European (Euro) and World Championships (WCh) between 2020 and 2023 and characterize the coaches’ perceptions.MethodsA mixed-methods approach was used, consisting of the following: (i) an observational methodology and instrument developed and validated to collect observational data on player and team behavior; and (ii) a developed and validated questionnaire to coaches on their perceptions of the 7 vs. 6 game. Observational data were collected during the Euro 2020 and 2022 games (n = 62) and the WCh 2021 and 2023 games (n = 70). A total of 132 games and 391 situations of 7 vs. 6 attacking sequences were observed. In total, 156 coaches participated (146 men), with a mean age 42.33 ± 11.87 years, 19 nationalities, and with 12.77 ± 9.45 years of experience.Results and discussionThe choice of 7 vs. 6 offensive play was mostly made in the second half (>73%). The effectiveness of 7 vs. 6 offensive sequences was higher in the top six teams than in the team's ranked 7th to 12th (Euro 2020 51.6%–50.0%; WCh 2021 52.0%–50.0%; Euro 2022 53.1%–41.7%; WCh 2023 50.0%–43.8%). Some patterns of association were found (p < 0.05 and with values >±1.96): (i) scoring a goal with a breakthrough shot was significantly associated with the effectiveness of the 7 vs. 6 attack (Euro 2020 2.61; WCh 2021 2.87; Euro 2022 2.68; WCh 2023 2.32); (ii) teams in the top six significantly used 7 vs. 6 when they were winning (Euro 2020 2.17; WCh 2021 3.52; Euro 2022 5.88; WCh 2023 2.54); and (iii) teams in the bottom six used it when they were losing by at least four goals (Euro 2020 7.56; Euro 2022 6.64; WCh 2023 4.37) or when they were winning by four goals or more (WCh 2021 2.58). Coaches that agree with the possibility of playing 7 vs. 6 (74.4%), rarely or never do so (55.6%) because it brings little or no advantage (52.6%). The results of the analysis confirmed the perception of the coaches, the low use of 7 vs. 6, the low advantage associated with it, and the influence of the result and the moment of the game on its use.
- Hikes and trails systematization of the types of obstacles/adaptations in pedestrian routesPublication . Fernando, Catarina; Fernando, Catarina; Vicente, António; Lopes, Hélder; Lopes, Helder; Prudente, João; Prudente, João FilipeHikes and trails are increasingly popular activities, in the field of tourism, but also at the level of recreational activities. With this work, we intend to create an integrative vision of the activity that includes the Situation / Context / Individual, which allows the development of instruments in order to enable an intervention, with a functional character, in this type of activities. To this end, we have systematized a set of adaptations requested from individuals, characteristics in the pedestrian paths, using the existing bibliography and an analysis of the obstacles identified in the activities.
- Soluble extracellular polymeric substances and microplastics: exposure-response and circular reuse for removalPublication . Rodrigues, Filipa; Mendonça, Ivana; Faria, Marisa; Gomes, Ricardo; Gómez Pinchetti, Juan L.; Ferreira, Artur; Cordeiro, Nereida; cordeiro, nereidaMicroplastics (MPs) are pervasive in aquatic systems, threatening ecosystems, human health, and microalgal production. Soluble extracellular polymeric substances (S-EPS) can agglomerate particles and aid removal. This study examines S-EPS from the cyanobacterium Cyanocohniella rudolphia (BEA 0786B) to (i) model and optimise S-EPS production, (ii) assess production in water contaminated with polystyrene MPs (PS-MPs), and (iii) test S EPS as a bioflocculant for PS-MPs removal. Response surface methodology (RSM) defined a cost-lean operating window and predicted an optimum S-EPS titre of 113 mg/L at 7 days using 10 g/L nitrogen, 0.98 g/L phosphorus, and a biomass-to-medium ratio of 1:6.87 (w/v). Cultures were challenged with PS-MPs (50 μg/L and 5 mg/L) under static or aerated conditions, and at both exponential and stationary phases, and showed stimulated S-EPS synthesis with increases of up to 34%, depending on hydrodynamics and growth stage. Purified S-EPS were evaluated as a bioflocculant at 2 g/L PS-MPs to probe robustness and rate-limiting mechanisms and to delineate a conservative operating window. Maximum removal of 82% was achieved in freshwater at pH 3.5 with Fe3+ 0.05% (w/w), 25 ◦C, S-EPS dose 400 mg/L (S-EPS:PS-MPs 1:5, w/w), and 60 min flocculation. Zeta potential trends and microscopy support charge neutralisation/bridging as the dominant mechanism. Compatible with standard coagulation/flocculation units, the approach links cost-lean, cultivation-derived S-EPS (typically dis carded) to their reuse as a low-additive pretreatment for algal-cultivation intake waters (freshwater/low salinity), reducing reliance on synthetic coagulants and added salinity/metal-sludge burdens. Overall, C. rudolphia is a promising S-EPS producer, whose production is enhanced by exposure to PS-MPs, and its S-EPS acts as an efficient, bio-based flocculant for PS-MPs. The results support process designs to safeguard microalgal operations and to mitigate microplastic pollution in water. This work integrates RSM-optimised S-EPS produc tion, environmental-level exposure-response, and a high-load removal benchmark, enabling circular, low additive, drop-in pretreatment compatible with standard coagulation/flocculation units.