Injury risks for fitness instructors: a review of key factors

The labour risks control is an occupational health concern. Fitness participants have been increasing in the last years (Lindwall, 2004). Clients’ demand and the increase in classes number take the fitness instructors (FI) to a higher injuries exposure due to high workload. It is possible to observe several variations in aerobic dance, cycling, pilates, strength training, flexibility and balance. The main differences are in the cardiovascular intensities and the low to high impact dance (Van Mechelen, Hlobil & Kemper, 1992). The FI are exposed to high volumes of classes and injuries risks due to the high number of students and classes (Couto et al., 2016). As far as our understanding goes, FI are 50% more prone to injuries incidence in comparison to students. Thus, the aim of this study was to assess by a bibliographic research the health and injuries risk in FI. This is a bibliographic review made in PUBMED, Google Scholar, SCIELO and Web of Science. The used keywords were “fitness instructors injuries”, “fitness professor’s injuries”, and “fitness instructor’s risks”. From an analysis of 23 papers, ten were chosen considering title and abstract. After a full integral analysis, only five papers were selected for revision. The others did not aimed to analyse the injuries and the health risks for FI. The selected papers approached the injuries and health risk factors for FI. There is a positive and significant correlation between the formation levels and injuries incidence prevention in FI and students (Malek, Nalbone, Berger & Coburn, 2002). FI with higher classification prevent higher frequency of injuries events. The injuries prevalence was superior in FI than in students (72.4 – 75.9% and 22.8 – 43.3% respectively) (Mutoh, Sawai, Takanashi & Skurko, 1998; Francis, Francis & Welshons-Smith, 1985). The injuries were general inflammations, muscle strains or sprains and stress fractures by overuse (Rothenberger, Chang & Cable, 1988). The FI are more exposed to injuries than students are (0.17 injuries/100h vs 0.15/100h of practice, respectively) and about 77% of the injuries were in the lower limbs (Garrick, Gillien & Whiteside, 1986). There is a lack of research in FI injuries risk of factors. However, FI seem to have a higher exposure to injuries in comparison to students. The high workload seem to be determinant to the incidence of overuse injuries.info:eu-repo/semantics/publishedVersio

The effects of 6-month multi-component exercise intervention on body composition in aged women: a single-arm experimental with follow-up study

Multicomponent exercise programs, which combine multiple modalities such as aerobic exercises, strength training exercises, flexibility exercises, and balance exercises, can help to promote healthy aging and prevent chronic diseases in aged women. Thus, the goal of this study is to examine if a multicomponent exercise program could improve body composition in community- dwelling aged women. A 6-month single-arm quasi-experimental research was conducted using a multicomponent exercise program for older adults. The sample included 38 women with a mean age of 63.50 years (SD = 6.47 years). Body composition and anthropometric measurement was conducted from baseline (T1), after intervention (T2), and follow-Up (T3). In addition, after exercise intervention, a significant difference with moderate to large effects was reported for fat mass [η2p = 0.374, p < 0.001)], bone density [η2p = 0.374, p < 0.05)], percentage of water [η2p = 0.374, p < 0.001)], and a metabolic equivalent task [η2p = 0.374, p < 0.05]. Additionally, a significant large effect size between T1 and T2 was verified. However, body composition indicators seem to decrease below baseline levels after concluding exercise intervention (T3). Muscle mass decreased significantly after exercise intervention and mean scores were lower compared to baseline data (T1). Thus, a positive effect of the multicomponent exercise program on body composition was established in this group of community-dwelling aged women. However, the relative improvement in body fat and muscle mass were lost after the exercise program’s conclusion for values below the baselines. Avoiding detraining periods is, therefore, fundamental to maintaining the normal relative body composition.This research was funded by national funds through the Portuguese Foundation for Science and Technology, I.P., grant number UIDB/04748/2020info:eu-repo/semantics/publishedVersio

Editorial: Towards a psychophysiological approach in physical activity, exercise, and sports

This Research Topic aims to look at specific themes related to physiological stress and mental well-being. Additionally, we aim to provide evidence to coaches and sports scientists highlighting the relationship between training and competition demands, related to performance. We also want to analyze the effects of strength and conditioning training, and coaching effects (acute and chronic) on psychological and physiological. Finally, it is our intention to provide scientific literature with evidence for a relationship between movement, behavior and cognition with physiological performance: the psychophysiological approach.info:eu-repo/semantics/publishedVersio

Perfis de força: velocidade no sprint em jogadores portugueses de futebol e futsal: um estudo piloto transversal

Background: Sprint running is a key factor of performance for team sports as football and futsal. Force-power-velocity relationships and mechanical effectiveness have been recently used to analyse force-velocity (F-V) profiles. The aim of this study was two-fold: (1) to quantify the sprint mechanical F-V profiles in Portuguese football and futsal players; (2) to analyse differences among sexes, competitive levels and sports on sprint mechanical variables in Portuguese football and futsal players. Methods: Four football players (2 mens) and four futsal players (2 mens), aged 26 ± 4.24 years, performed a 3 maximal sprints of 30 m from a standing position with 4 min of rest between successive sprints. Video data was collected with a Go Pro Hero (Full HD 1080p, 30 fps). Force-velocity profile was obtained with time motion data: F0 (N/kg), V0 (m/s), Pmax (W/kg), Sfv, RFmax (%), DRF (%), Vopt (m/s) and max speed (m/s). Results: Men’s players showed a higher V0 (t = -7.12;p<0.001,d=5.04),Vopt (t=-2.90;p≤ 0.05,d=2.05)andmaxspeed(t=-5.09;p≤ 0.05, d = 3.60) than women players. No differences with statistical significance were observed among competitive levels and sports. Conclusion: These results showed that the sprint mechanical F-V profiles is able to distinguish between men and women football and futsal players. No differences among competitive levels could be due to the low competitive level of the sample. Future research should include different competitive level such as elite, sub-elite and recreational.Enqudramento – O sprint é um fator determinante para o desempenho em desportos coletivos como o futebol e o futsal. As relações força-potência-velocidade e eficácia mecânica têm sido recentemente utilizadas para analisar perfis de força-velocidade (F-V). O objetivo deste estudo era duplo: (1) quantificar os perfis biomecânicos F-V do sprint em jogadores de futebol e futsal portugueses; (2) analisar diferenças entre sexos, níveis competitivos e desportos nas variáveis em estudo. Métodos – 4 jogadores de futebol (2 homens) e 4 jogadores de futsal (2 homens), com 26 ± 4,24 anos, realizaram 3 sprints máximos de 30 m a partir de uma posição de pé com 4 min de descanso entre sprints sucessivos. Foram recolhidos dados de vídeo com um Go Pro Hero (Full HD 1080p, 30 fps). O perfil de força- velocidade foi obtido com: F0 (N/kg), V0 (m/s), Pmax (W/kg), Sfv, RFmax (%), DRF (%), Vopt (m/s) e velocidade máxima (m/s). Results – Os jogadores masculinos mostraram umV0 (t=-7,12;p<0,001,d=5,04),Vopt (t=- 2,90; p ≤ 0,05, d = 2,05) e velocidade máxima (t =-5,09;p≤0,05,d=3,60)maisaltadoque nas jogadoras femininas. Não foram observadas diferenças com significado estatístico entre os níveis competitivos e o desporto. Conclusão – Estes resultados mostraram que os perfis mecânicos de sprint (F-V) são capazes de diferenciar entre jogadores masculinos e femininos de futebol e jogadores de futsal. Nenhuma diferença entre os níveis competitivos pode dever-se ao baixo nível competitivo da amostra. A investigação futura deve incluir diferentes níveis competitivos, tais como elite, subelite e recreativo.info:eu-repo/semantics/publishedVersio

Integrating physical and tactical factors in football using positional data: a systematic review

Positional data have been used to capture physical and tactical factors in football, however current research is now looking to apply spatiotemporal parameters from an integrative perspective. Thus, the aim of this article was to systematically review the published articles that integrate physical and tactical variables in football using positional data. Methods and Materials: Following the Preferred Reporting Item for Systematic Reviews and Meta-analyses (PRISMA), a systematic search of relevant English-language articles was performed from earliest record to August 2021. The methodological quality of the studies was evaluated using the modified Downs and Black Quality Index (observational and cross-sectional studies) and the Physiotherapy Evidence Database (PEDro) scale (intervention studies). Results: The literature search returned 982 articles (WoS = 495; PubMed = 232 and SportDiscus = 255). After screening, 26 full-text articles met the inclusion criteria and data extraction was conducted. All studies considered the integration of physical and tactical variables in football using positional data (n = 26). Other dimensions were also reported, such as psychophysiological and technical factors, however the results of these approaches were not the focus of the analysis (n = 5). Quasi-experimental approaches considered training sets (n = 20) and match contexts (n = 6). One study analysed both training and play insights. Small sided-games (SSG) were the most common training task formats in the reviewed studies, with only three articles addressing medium-sided (MSG) (n = 1) and large-sided games (LSG) (n = 2), respectively. Conclusions: Among the current systematic review, the physical data can be integrated by player’s movement speed. Positional datasets can be computed by spatial movement, complex indexes, playing areas, intra-team and inter-team dyads. Futures researches should consider applying positional data in women’s football environments and explore the representativeness of the MSG and LSG.This research was supported by Portuguese Foundation for Science and Technology, I.P. (project UIDB/04045/2020). The funders had no role in study design, data collection and analysis, decision to publish, or preparation of the manuscriptinfo:eu-repo/semantics/publishedVersio

Effects of match location, quality of opposition and match outcome on match running performance in a Portuguese professional football team

The aim of this study was to analyze the effects of match location, quality of opposition and match outcome on match running performance according to playing position in a Portuguese professional football team. Twenty-three male professional football players were monitored from eighteen Portuguese Football League matches during the 2019–2020 season. Global positioning system technology (GPS) was used to collect time-motion data. The match running performance was obtained from five playing positions: central defenders (CD), fullbacks (FB), central midfielders (CM), wide midfielders (WM) and forwards (FW). Match running performance was analyzed within specific position and contextual factors using one-way analysis of variance (ANOVA) for repeated measures, standardized (Cohen) differences and smallest worthwhile change. CM and WM players covered significantly greater total distance (F = 15.45, p = 0.000, η2 = 0.334) and average speed (F = 12.79, p < 0.001, η2 = 0.294). WM and FB players covered higher distances at high-speed running (F = 16.93, p = 0.000, η2 = 0.355) and sprinting (F = 13.49; p < 0.001, η2 = 0.305). WM players covered the highest number of accelerations (F = 4.69, p < 0.001, η2 = 0.132) and decelerations (F = 12.21, p < 0.001, η2 = 0.284). The match running performance was influenced by match location (d = 0.06–2.04; CI: −0.42–2.31; SWC = 0.01–1.10), quality of opposition (d = 0.13–2.14; CI: –0.02–2.60; SWC = 0.01–1.55) and match outcome (d = 0.01–2.49; CI: −0.01–2.31; SWC = 0.01–0.35). Contextual factors influenced the match running performance with differential effects between playing positions. This study provides the first report about the contextual influence on match running performance in a Portuguese professional football team. Future research should also integrate tactical and technical key indicators when analyzing the match-related contextual influence on match running performanceThis research was supported by the Douro Higher Institute of Educational Sciences and the Portuguese Foundation for Science and Technology, I.P. (project UIDB04045/2021)info:eu-repo/semantics/publishedVersio

Methodological procedures for non-linear analyses of physiological and behavioural data in football

Complex and dynamic systems are characterised by emergent behaviour, self-similarity, self-organisation and a chaotic component. In team sports as football, complexity and non-linear dynamics includes understanding the mechanisms underlying human movement and collective behaviour. Linear systems approaches in this kind of sports may limit performance understanding due to the fact that small changes in the inputs may not represent proportional and quantifiable changes in the output. Thus, non-linear approaches have been applied to assess training and match outcomes in football. The increasing access to wearable and tracking technology provides large datasets, enabling the analyses of time-series related to different performance indicators such as physiological and positional parameters. However, it is important to frame the theoretical concepts, mathematical models and procedures to determine metrics with physiological and behavioural significance. Additionally, physiological and behavioural data should be considered to determine the complexity and non-linearity of the system in football. Thus, the current chapter summarises the main methodological procedures to extract positional data using non-linear analyses such as entropy scales, relative phase transforms, non-linear indexes, cross correlation, fractals and clustering methods.This research was supported by Portuguese Foundation for Science and Technology, I.P. (project UIDB04045/2021).info:eu-repo/semantics/publishedVersio

Aerodynamic analysis of human walking, running and sprinting by numerical simulations

The drag in walking, running, and sprinting locomotion can be assessed by analytical procedures and experimental techniques. However, assessing the drag variations by these three main locomotion’s (i.e., walking, running, and sprinting) were not found using computational fluid dynamics. (CFD). Thus, the aim of this study was two-fold: (1) to assess the aerodynamics of human walking, running, and sprinting by CFD technique; 2) compare such aerodynamic characteristics between walking and running. Three 3D models were produced depicting the walking, running, and sprinting locomotion techniques, converted to computer aided design models and meshed. The drag varied with 4 locomotion type. Walking had the lowest drag, followed-up by running and then sprinting. At the same velocities, the drag was larger in walking than in running and increased with velocity. In conclusion, drag varied with locomotion type. Walking had the lowest drag, followed-up by running and then sprinting. At the same velocities, the drag was larger in walking than in running and increased with velocity.This project was founded by the Portuguese Foundation for Science and Technology, I.P. (project UIDB04045/2020)info:eu-repo/semantics/publishedVersio