Effects of changing the head coach on soccer team's performance: A systematic review.

The aim of this review was to identify and synthesise the most significant literature addressing the effects of changing the HC on soccer team's performance, identifying the most frequently researched outcomes and characterizing their methodologies. A systematic review of PubMed, Scopus, Web of Science and SPORTDiscus databases was performed according to the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA, 2020) guidelines. The following keywords and synonyms were entered in various combinations in the title, abstract or keywords: "football*" OR soccer AND "coach*" OR "manager*" AND "replacement" OR "turnover" OR "substitution*" OR "change". Solely original articles written in English that contained data about the effects of the change in the HC on performance in professional male soccer were included. A total of 94 titles were identified, of which 24 met the eligibility criteria. The quality of the studies was considered excellent. The most common topic of analysis was the effects of the HC on match outcomes (i.e., win, draw, loss, points won, goals average). Some studies suggest that the HCs dismissal has small but positive impacts on a team's short-term performance, while other findings suggest that little-to-no impact is observed following HC departure. The dismissal of the HC does not guarantee increase success of an underperforming team. Some studies suggest that hiring an appropriate coach could positively affect match performance in the short-term. Due to limited variations in study designs, further research is needed before robust conclusions can be drawn.

Contemporary practices of Portuguese and Brazilian soccer coaches in designing and applying small-sided games.

This descriptive study aimed to investigate the current practices of Portuguese and Brazilian soccer coaches in the design and implementation of small-sided games (SSGs) in soccer. A total of 187 male coaches participated in the online survey, consisting of 82 Portuguese and 105 Brazilian individuals. These coaches held various positions within the technical staff, with 63 serving as head coaches, 38 as assistant coaches, 38 as physical trainers, and 48 in other roles related to the technical staff. Additionally, the participants represented both youth (n = 102) and adult competitive levels (n = 59), along with some who were not currently associated with a specific group. The survey consisted of 32 questions divided into three main sections: (i) the timing of SSG application, (ii) the methods used for applying SSGs, and (iii) the reasons for applying SSGs. The Chi-square test revealed a statistically significant association between nationality and the frequency of SSGs used in training sessions during the pre-season (p = 0.039) and in-season (p < 0.001). Moreover, significant association between nationality and the time allocated to employing SSGs for targeting aerobic training (p < 0.001) was found. There was a significant association between nationality and the weekly frequency of SSGs use for targeting sprint training (p = 0.019). The Chi-square test identified significant associations between nationality and the use of SSGs for targeting technical training (p = 0.002), as well as for tactical training (p = 0.002). In summary, this study underscores that SSGs are primarily employed to enhance aerobic fitness, change of direction, technical skills, and tactical behaviors. Coaches generally favor employing SSGs two to three times a week, with typical sessions lasting between 16 to 30 minutes. Notably, the major discrepancies between nationalities lie in the importance assigned to the use of SSGs. However, in practice, the formats and objectives for implementing SSGs remain relatively similar.

The Quantification of Physical Performance and Internal Training Load in Youth Male Soccer Players During Preseason.

PURPOSE: The monitoring of training loads and quantification of physical performance are common practices in youth soccer academies to support coaches in prescribing and programming training for individuals. The interaction between training load and physical performance is unknown during a preseason period in youth soccer players. The current study assessed changes in training load and physical assessments across a 4-week preseason period. The relationship between physical performance and match playing time in youth male soccer players was also investigated. METHODS: The training loads of 25 professional youth academy male soccer players were monitored throughout a 4-week preseason period. Assessments of power, agility, speed, and aerobic capacity were undertaken in the first training session. Session ratings of perceived exertion (sRPE) and well-being questionnaires were collected during all training sessions and preseason matches. Playing time during subsequent competitive matches was recorded. RESULTS: T test and 30-m-sprint assessments, conducted on the first day of preseason, were predictors of sRPE throughout preseason (t test χ2/df = 2.895, poor adjustment; 30-m sprint χ2/df = 1.608, good adjustment). YoYo Test performance was related with changes in perceived fatigue (χ2/df = 0.534, very good adjustment). Faster players reported higher values of sRPE, and players with higher aerobic capacity reported higher levels of fatigue across preseason. Well-being, perceived fatigue and soreness, and sRPE decreased across preseason. Greater match durations were related to higher levels of fatigue during preseason (P < .05). CONCLUSION: The current study highlights the relationship between training load, physical assessments, and playing time. Coaches and practitioners can use physical test data at the start of preseason as an indication of players that report higher sRPE, perceived fatigue, and reduced well-being across preseason, supporting decisions around individualized training prescriptions.

What We Do Not Know About Stretching in Healthy Athletes: A Scoping Review with Evidence Gap Map from 300 Trials.

BACKGROUND: Stretching has garnered significant attention in sports sciences, resulting in numerous studies. However, there is no comprehensive overview on investigation of stretching in healthy athletes. OBJECTIVES: To perform a systematic scoping review with an evidence gap map of stretching studies in healthy athletes, identify current gaps in the literature, and provide stakeholders with priorities for future research. METHODS: Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) 2020 and PRISMA-ScR guidelines were followed. We included studies comprising healthy athletes exposed to acute and/or chronic stretching interventions. Six databases were searched (CINAHL, EMBASE, PubMed, Scopus, SPORTDiscus, and Web of Science) until 1 January 2023. The relevant data were narratively synthesized; quantitative data summaries were provided for key data items. An evidence gap map was developed to offer an overview of the existing research and relevant gaps. RESULTS: Of ~ 220,000 screened records, we included 300 trials involving 7080 athletes [mostly males (~ 65% versus ~ 20% female, and ~ 15% unreported) under 36 years of age; tiers 2 and 3 of the Participant Classification Framework] across 43 sports. Sports requiring extreme range of motion (e.g., gymnastics) were underrepresented. Most trials assessed the acute effects of stretching, with chronic effects being scrutinized in less than 20% of trials. Chronic interventions averaged 7.4 ± 5.1 weeks and never exceeded 6 months. Most trials (~ 85%) implemented stretching within the warm-up, with other application timings (e.g., post-exercise) being under-researched. Most trials examined static active stretching (62.3%), followed by dynamic stretching (38.3%) and proprioceptive neuromuscular facilitation (PNF) stretching (12.0%), with scarce research on alternative methods (e.g., ballistic stretching). Comparators were mostly limited to passive controls, with ~ 25% of trials including active controls (e.g., strength training). The lower limbs were primarily targeted by interventions (~ 75%). Reporting of dose was heterogeneous in style (e.g., 10 repetitions versus 10 s for dynamic stretching) and completeness of information (i.e., with disparities in the comprehensiveness of the provided information). Most trials (~ 90%) reported performance-related outcomes (mainly strength/power and range of motion); sport-specific outcomes were collected in less than 15% of trials. Biomechanical, physiological, and neural/psychological outcomes were assessed sparsely and heterogeneously; only five trials investigated injury-related outcomes. CONCLUSIONS: There is room for improvement, with many areas of research on stretching being underexplored and others currently too heterogeneous for reliable comparisons between studies. There is limited representation of elite-level athletes (~ 5% tier 4 and no tier 5) and underpowered sample sizes (≤ 20 participants). Research was biased toward adult male athletes of sports not requiring extreme ranges of motion, and mostly assessed the acute effects of static active stretching and dynamic stretching during the warm-up. Dose-response relationships remain largely underexplored. Outcomes were mostly limited to general performance testing. Injury prevention and other effects of stretching remain poorly investigated. These relevant research gaps should be prioritized by funding policies. REGISTRATION: OSF project ( https://osf.io/6auyj/ ) and registration ( https://osf.io/gu8ya ).

One more step in solving the Chydorus puzzlea morphological comparison between Chydorus tilhoi Rey & Saint-Jeans, 1969 and Chydorus sphaericus (O.F. Mller, 1776) (Crustacea: Cladocera).

A number of species of Chydorus Leach, 1816 (Crustacea: Cladocera) need improvements in their taxonomy much more than any other genus within the family Chydoridae Dybowsky & Grochowski, 1894 emend. Frey, 1967, which makes the systematics of the genus still a puzzle that lacks several pieces. Here, we redescribe the African species Chydorus tilhoi Rey & Saint-Jeans, 1969 and compare its morphology with that of Chydorus sphaericus (O.F. Mller, 1776). The two taxa might be easily differentiated because C. tilhoi has a single and relatively large major head pore with a wide rim, labral keel elongated with a large spine, and postabdomen with postanal part elongated, narrowing distally and with denticles near its anal margin, organized in groups. These morphological traits are absent in C. sphaericus. Chydorus tilhoi and C. sphaericus also differ in the morphology of the first (Inner Distal Lobe setae), third (exopodite proportion), and fifth (exopodite shape) limbs. Based on the literature and our observations, the limb morphology of C. tilhoi has important similarities with that of C. breviceps, C. nitidulus and C. dentifer, and their translocation to a new genus seems to be a fundamental piece in the puzzle of Chydorus.

Effects of small-sided games training programs on physiological and physical adaptations of youth basketball players: A systematic review.

The primary objective of this study was to systematically investigate the physiological and physical fitness adaptations resulting from small-sided games (SSGs) training programs in basketball players competing at youth competitive levels, as compared to other training approaches and/or control groups. To achieve this, we conducted a literature search on PubMed, Scopus, SPORTDiscus, and Web of Science, adhering to the Preferred Reporting Items for Systematic Reviews and Meta-Analyses guidelines. From the initial 626 studies retrieved, five were considered eligible for the current study. Among the five included articles, four conducted comparisons between the effects of SSGs and running-based high-intensity interval training. Regarding this, the four studies revealed a significant improvement in the final velocity during the 30-15 Intermittent Fitness Test, ranging from 4.07% to 7.29% following SSG-based interventions. This improvement was not significantly different from the comparator group. Additionally, two studies indicated that the SSGs group showed a significant advantage in change-of-direction time, with improvements ranging from -2.11% to 6.69% after interventions, and these results were not significantly different from the comparator group. However, the effects on repeated sprint ability yielded contradictory findings; two studies reported significant improvements ranging from -5.00% to -2.16%, while two others did not show significant effects following SSGs-based interventions. Similarly, in the linear sprint, the results of SSGs-based interventions were inconsistent. In summary, based on the available research, it can be concluded that SSG-based training is effective in significantly enhancing aerobic performance and change of direction, comparable to alternative approaches. However, the effects on repeated sprint ability and sprint performance are not consistently demonstrated.

Lower limbs strength variations between injured and non-injured professional soccer players.

Due to its physical demands, professional soccer is becoming a real challenge regarding players' exposure to high injury risk. Given its tight correlation with high-intensity actions, muscular strength is a crucial physical characteristic for soccer players. Therefore, the aims of this study are (a) to compare the vertical jumping performance during the season according to the injury profile, and (b) to investigate differences in isokinetic strength performance at the beginning and the end of the season. Twenty-one male professional soccer players (age: 26.0 ± 4.1 years, height: 181.0 ± 6.9 cm, body mass: 73.7 ± 6.9 kg) were assessed in isokinetic strength (Biodex System 4 Pro Dynamometer), and Optojump Next (Microgate, Bolzano, Italy). Isokinetic strength analyses considered the peak torque scores of knee flexors and knee extensors, according to the player's preferred and non-preferred limb. The countermovement and squat jump maximum height were assessed as lower body explosive strength indicators. No significant differences were found when comparing injured and non-injured players in vertical jump and isokinetic strength assessments. However, significant results were found when comparing both groups' initial and final evaluation in isokinetic strength assessment, with both groups significantly improving their performance. Our findings indicate that the overall lower body strength performance was not a discriminant factor between injured and non-injury players. Thus, muscular strength assessment performance increased throughout the season independently of the injury profile. Future research needs to integrate other variables related to sports injuries since they seem to result from multifactorial causes.

Tracking devices and physical performance analysis in team sports: a comprehensive framework for research-trends and future directions.

Background: Tracking devices, such as global (GPS) and local (LPS) positioning systems, combined with physiological measurements, have become reliable tools to characterize movement patterns, assessing the external load (EL), internal load (IL), fatigue, and performance of athletes in team sports. This scoping review aims to provide a comprehensive understanding of the applicability of tracking systems in physical performance analysis within team sports and the wellbeing of athletes based on research strategies and combined variables. Methods: A systematic search was conducted in PubMed, Web of Knowledge, and Scopus databases according to PRISMA guidelines. The 79 studies that were reviewed met the following criteria: (1) contained relevant data regarding elite athletes' performance; (2) athletes' EL and IL; (3) were written in the English language; (4) were related only to team sports. Results: The findings indicate that tracking technology has been engaged in several research areas, including performance analysis, training vs. match load management, injuries, and nutrition, through characterization and correlational studies. Metrics, primarily focused on kinematic and mechanical EL aspects, have been employed in combination with IL data to analyze the performance of athletes. However, the lack of an integrative model for the analysis and integration of EL and IL metrics within each team sport suggests an interesting direction for further research. Conclusion: There is a need for coherence between the methods and the research goals on performance analysis. The development of a framework that guides experimental studies is highly recommended, particularly on manipulating metrics analyzed between training and match sessions, injury prevention, and nutrition. This will lead to the development of the most applied sports science research to improve the preparation and decision-making of athletes based on reliable data. Systematic Review Registration: https://inplasy.com/?s=2022120039, identifier 2022120039.

Physical predictors for retention and dismissal of professional soccer head coaches: an analysis of locomotor variables using logistic regression pipeline.

Introduction: Soccer has enormous global popularity, increasing pressure on clubs to optimize performance. In failure, the tendency is to replace the Head coach (HC). This study aimed to check the physical effects of mid-season replacements of HCs, investigating which external load variables can predict retention or dismissal. Methods: The data was collected in training and matches of a professional adult male soccer team during three complete seasons (2020/21-2022/2023). The sample included 6 different HCs (48.8 ± 7.4 years of age; 11.2 ± 3.9 years as a HC). The 4 weeks and 4 games before and after the replacement of HCs were analysed. External load variables were collected with Global Positioning System (GPS) devices. A logistic regression (LR) model was developed to classify the HCs' retention or dismissal. A sensitivity analysis was also conducted to determine the specific locomotive variables that could predict the likelihood of HC retention or dismissal. Results: In competition, locomotor performance was better under the dismissed HCs, whereas the new HC had better values during training. The LR model demonstrated a good prediction accuracy of 80% with a recall and precision of 85% and 78%, respectively, amongst other model performance indicators. Meters per minute in games was the only significant variable that could serve as a potential physical marker to signal performance decline and predict the potential dismissal of an HC with an odd ratio of 32.4%. Discussion: An in-depth analysis and further studies are needed to understand other factors' effects on HC replacement or retention.

Effects of recreational small-sided games from different team sports on the improvement of aerobic fitness in youth sedentary populations: A systematic review.

Aerobic fitness is a critical aspect of overall health and well-being, essential for maintaining a high quality of life. Unfortunately, sedentary behavior has been on the rise among young adults, and this has had a negative impact on their aerobic fitness levels. Therefore, it is crucial to identify enjoyable physical exercise training programs that can play a pivotal role in improving aerobic fitness. The objective of this study was to systematically review the experimental studies concerning the impact of small-sided games (SSGs) training programs, implemented across various team sports, on the enhancement of aerobic fitness in a youth sedentary population. A literature search was conducted in PubMed, Scopus, and the Web of Science on August 01, 2023. Our eligibility criteria focused on studies involving sedentary youth populations (aged <18 years) as the target population. These studies needed to incorporate interventions based on SSGs as the intervention of interest, comparing them to passive or control groups as the comparator. The primary outcomes of interest were related to maximal oxygen uptake (VO2max), assessed either directly or indirectly, or the results of field-based cardiorespiratory tests. We specifically considered two- or multi-arm randomized controlled studies as the study design of interest. Out of the initial pool of 1980 studies, we reviewed 38 full-text articles, ultimately selecting and analyzing 13 studies for inclusion in our review. Among the studies included, a total of 1281 participants were enrolled in SSG-based interventions, while 744 participants acted as part of the control groups. Regarding the impact on VO2max, the six studies that investigated this outcome showed varying improvements, ranging from 2.2 % to 31.3 % when participants were exposed to SSGs. In terms of the outcome related to endurance performance in field-based tests, the eight studies that examined this aspect found that participants exposed to SSGs showed improvements ranging from 0.1 % to 79.8 %. In conclusion, this systematic review suggests that SSG-based interventions conducted among sedentary youth populations can play a positive role in improving their aerobic fitness. This improvement in aerobic fitness can have potential positive impacts on their overall health and quality of life.

Global biogeography of the smallest plankton across ocean depths.

Tiny ocean plankton (picoplankton) are fundamental for the functioning of the biosphere, but the ecological mechanisms shaping their biogeography were partially understood. Comprehending whether these microorganisms are structured by niche versus neutral processes is relevant in the context of global change. We investigate the ecological processes (selection, dispersal, and drift) structuring global-ocean picoplanktonic communities inhabiting the epipelagic (0 to 200 meters), mesopelagic (200 to 1000 meters), and bathypelagic (1000 to 4000 meters) zones. We found that selection decreased, while dispersal limitation increased with depth, possibly due to differences in habitat heterogeneity and dispersal barriers such as water masses and bottom topography. Picoplankton ß-diversity positively correlated with environmental heterogeneity and water mass variability, but this relationship tended to be weaker for eukaryotes than for prokaryotes. Community patterns were more pronounced in the Mediterranean Sea, probably because of its cross-basin environmental heterogeneity and deep-water isolation. We conclude that different combinations of ecological mechanisms shape the biogeography of the ocean microbiome across depths.

Contemporary practices of physical trainers in professional soccer: A qualitative study.

Introduction: Physical trainers (PTs) are integral for managing load, reducing injury and optimizing performance in professional soccer. However, little is known about how this practitioners operate in the applied setting and how some of the nuances experienced influence practice. Methods: This study explored the contemporary practices of PTs in professional soccer. Semi-structured interviews were undertaken with eight PTs from different professional teams in European and South American leagues. Interview questions were designed to extract information on the evaluation of physical abilities, monitoring and control of training and injury prevention. Subsequently, the interviews were video-recorded, transcribed, translated and analyzed using a content analysis approach. Results: The results suggest that the evaluation of physical capacities is carried out by PTs at the beginning of the preseason. It also appears that it is attempted that this process of regular testing is applied during the competitive period, with most participants conducting partial physiological and physical evaluations at different stages throughout the competitive season. In relation to the monitoring and control of training, subjective feedback scales are used to estimate the internal load, and the use of GPS devices is common to quantify external loads. Injury prevention programmes were implemented by all participants and were generally in a multi-component format focused on preventing or optimizing physical capabilities. Discussion: These insights can be used as a scientific reference point to inform applied practice in professional soccer, especially for practitioners that are inexperienced and aspiring to enhance how they operate in the field. Future investigations should explore the practices of PTs in detail and across a wider network in order to gain deeper and comprehensive insights into the applied soccer environment.

A Systematic Review of the Physical, Physiological, Nutritional and Anthropometric Profiles of Soccer Referees.

BACKGROUND: The importance of soccer referees is widely accepted by international soccer organizations and governing bodies, although there is little research summarizing and appraising the literature on soccer referees. The aim of this study was to systematically review the information related to physical demands, nutrition and physiological profiling of soccer referees. METHODS: Conforming with Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines, searches of three electronic databases (Web of Sciences, PubMed and Scopus) were conducted on 24 April 2022. The following search terms were used: (Soccer OR football AND refer*) AND (physical OR physiolo* OR load* OR "body composition" OR "fat mass" OR "fat free mass" OR "body size" OR "nutrition*" OR "nutritional assessment" OR "nutritional intake" OR "macronutrient*" OR "micronutrient*"). The inclusion criteria of the manuscripts written in English were that articles with male and/or female soccer referees and included relevant data concerning performance, physical testing, nutrition, body composition, body size and/or physiology of soccer referees. The tools developed by the National Institute of Health were used to assess risk of bias according to the study design. RESULTS: In total, 110 manuscripts were included in the present review. Match activities of soccer referees and assistant referees are not comparable. Variation in performance is influenced by competitive level and competitive schedules. Additionally, match performance is often used to validate field protocols. The associations between match indicators and field protocols were not constant across the included studies, particularly in short-maximal tests. An age decline in physical performance was not conclusive. Body size did not discriminate between referees and assistant referees, as well as referees of different competitive levels. Few studies focused on nutritional guidelines among referees, particularly exercise energy expenditure. Energy intake was comparable across studies, but referees did not follow the daily dietary recommendations. Aerobic output was frequently assessed, and it was not comparable to the values for soccer players. CONCLUSIONS: Although there are decreases in the running profiles of older referees, they maintain the same distances from the ball, and thus, age per se should not be used to define participation at the international level. The assessment of physical fitness warrants future consideration given the levels of fatigue that are apparent at the end of matches. In order to attain ideal levels of body composition, future studies need to provide guidelines for daily energy expenditure and nutritional intake. TRIAL REGISTRATION: The protocol was published in INPLASY (International Platform of Registered Systematic Review and Meta-Analysis Protocols) with the registration number 202280052 and https://doi.org/10.37766/inplasy2022.8.005 .

Predicting resting energy expenditure among athletes: a systematic review.

Resting energy expenditure (REE) is often estimated in athletes using equations developed from the general population however, the application in athletic-specific populations is questionable. The aim of this systematic review was to compare measured REE and estimations of REE obtained from non-sport participants and athletes. Inclusion criteria met PICO criteria: population - participants involved in organized sport; intervention - resting energy expenditure was obtained by calorimetry; comparator - equations to estimate REE; outcomes - comparisons between measured REE and predicted REE. The search was conducted in Web of Science all databases, PubMed and Scopus. Comparisons between measured REE and predicted REE as well the potential models to estimate REE developed among athletes were summarized. Allowing for variation among studies, equations developed within general populations were not comparable to REE measured by calorimetry in athletes. Equations across athletic samples were obtained but, few studies tested their validity across independent samples of sport participants. Nevertheless, equations developed within athlete populations seem to be widely unused in sports nutrition literature and practice. De Lorenzo and ten Haaf equations appear to present an acceptable agreement with measured REE. Finally, equations used among adults should not be generalised for youth sport participants.

Arbitrary absolute vs. individualized running speed thresholds in team sports: A scoping review with evidence gap map.

The aims of this scoping review were (i) to characterize the main methodological approaches to assessing individualized running speed thresholds in team sports players; (ii) to assess the use of traditional arbitrary (absolute) thresholds compared to individualized running speed thresholds in team sports players; (iii) to provide an evidence gap map (EGM) about the approaches and study designs employed in investigations in team sports and (iv) to provide directions for future research and practical applications for the strength and conditioning field. Methods studies were searched for in the following databases: (i) PubMed; (ii) Scopus; (iii) SPORTDiscus and (iv) Web of Science. The search was conducted on 15/07/2022. Risk of bias was assessed using the Risk of Bias Assessment Tool for Nonrandomized Studies (RoBANS). From 3,195 potentially relevant articles, 36 were eligible for inclusion in this review. Of the 36 included articles, 27 (75%) focused on the use of arbitrary and individualized running speed thresholds to describe the locomotor demands (e.g., high intensity running) of players. Thirty-four articles used individualized speed running thresholds based on physical fitness assessments (e.g., 40-m linear sprint) or physical performance (e.g., maximal acceleration). This scoping review supported the need for a greater focus to be placed on improving the methodological aspects of using individualized speed running thresholds in team sports. More than just creating alternatives to arbitrary thresholds, it is essential to increase the replicability of methodological conditions whilst ensuring that research comparing the most adequate measures and approaches to individualization takes into consideration the population and context of each study.

Building Bridges Instead of Putting Up Walls: Connecting the "Teams" to Improve Soccer Players' Support.

The increase in the economic value of soccer occurred in parallel with an increase in competing demands. Therefore, clubs and federations evolved to greater specialization (e.g., state-of-the-art facilities and high-profile expertise staff) to support players' performance and health. Currently, player preparation is far from exclusively club or national team centered, and the lack of control in each player's environment can be more prevalent than expected. For example, an elite group of professional players faces disruptions in the season club-oriented planification due to involvement in national teams. Moreover, as elite players' financial resources grow, it is common for them to employ specialized personal staff (e.g., strength and conditioning, nutritionist, and sports psychologist) to assist in their preparation, resulting in complex three-fold relationships (i.e., club, player's staff, national team). Although efforts have been made to improve communication with and transition from the club to the national team supervision, this new reality (club-players' staff) may generate serious compound role-related problems and difficulties in monitoring load and training adaptation and having a unified message. Therefore, efforts must be implemented to ensure a more informed management of the players' performance environment, where the existence and impact of these various personal staff are considered to avoid a long-term non-zero sum for all intervening parties. If left unchecked, current professional thinking may collide or overlap, potentially triggering conflict escalation and impairing athletic performance or health, especially if effective communication routes are not adequately established. Moreover, diluted personal responsibility regarding performance may ensue, resulting in decreased productivity from all involved, which may cause more harm than benefits for the player's overall health and performance. This emerging reality calls for developing a joint working framework (i.e., between the player's personalized support team and the clubs' team) and better managing of a player-centered process.

From ecological functions to ecosystem services: linking coastal lagoons biodiversity with human well-being.

In this review we highlight the relevance of biodiversity that inhabit coastal lagoons, emphasizing how species functions foster processes and services associated with this ecosystem. We identified 26 ecosystem services underpinned by ecological functions performed by bacteria and other microbial organisms, zooplankton, polychaetae worms, mollusks, macro-crustaceans, fishes, birds, and aquatic mammals. These groups present high functional redundancy but perform complementary functions that result in distinct ecosystem processes. Because coastal lagoons are located in the interface between freshwater, marine and terrestrial ecosystems, the ecosystem services provided by the biodiversity surpass the lagoon itself and benefit society in a wider spatial and historical context. The species loss in coastal lagoons due to multiple human-driven impacts affects the ecosystem functioning, influencing negatively the provision of all categories of services (i.e., supporting, regulating, provisioning and cultural). Because animals' assemblages have unequal spatial and temporal distribution in coastal lagoons, it is necessary to adopt ecosystem-level management plans to protect habitat heterogeneity and its biodiversity, ensuring the provision of services for human well-being to multi-actors in the coastal zone.

Methodological considerations for determining the volume and intensity of drop jump training. A systematic, critical and prepositive review.

This systematic review provides critical and propositional information on criteria for determining the volume and intensity of drop jumps during plyometric training programs. Eligibility criteria were defined according to PICOS: Participants: male or female athletes, trained or recreationally active (16-40 years). Intervention duration: more than 4 weeks. COMPARATORS: passive or active control group during a plyometric training program. OUTCOMES: information on improvement with Drop Jump or Depth Jump, with other jumps, acceleration, sprint, strength, and power output. DESIGN: randomized controlled trials. We searched articles published in PubMed, SPORTDiscus, Web of Science, and Scopus. The search was conducted until 10 September 2022 for English-language articles only. The risk of bias was assessed using Grading of Recommendations, Assessment, Development and Evaluation (GRADE) for randomized controlled studies. We identified 31495 studies, of which only 22 were included. We found that six groups presented results with women, 15 presented results with men, and the remaining four presented mixed studies. Of the 686 people recruited, 329 participants aged 25.79 ± 4.76 years were involved in training. Methodological problems in training intensity, volume distribution, and individualization were noted, but methodological recommendations for their solution are also provided. It is concluded that the drop height should not be understood as the intensity determinant of plyometric training. Intensity is determined by ground reaction forces, power output, and jump height, among other factors. Furthermore, the athletes' experience level selection should be based on the formulas recommended within this research. These results could be helpful for those who intend to conduct new plyometric training programs and research.

Dietary intakes and daily distribution patterns of macronutrients in youth soccer players.

Introduction: There has been an abundance of dietary analysis research conducted on adult male soccer players, while studies on youth players are lacking. Furthermore, the daily distribution of energy and macronutrient intake throughout the day has been reported to influence training adaptations, but this is often not considered in the literature. This study aims to quantify daily energy and macronutrient intake and assess their distribution over 5 days, and compare daily energy intakes and predicted daily energy expenditure in under-16 male soccer players. Methods: The sample included 25 soccer participants aged 14.8-15.7 years. Five-day self-reported food diaries were used to record the food/drink consumption. Intake was analyzed for total daily energy, macronutrient intakes, and distribution among meals (breakfast, lunch, dinner, and snacks). Daily energy expenditure was predicted by resting energy expenditure and physical activity levels developed for youth sports participants. Results: The mean total energy intake was 1,928 ± 388 kcal∙day-1, whereas the estimated daily energy expenditure was 3,568 kcal∙day-1. Relative daily protein intakes were lower at breakfast, morning snack, afternoon snack, and night snack compared to lunch and dinner. Discussion: Youth soccer players do not appear to meet energy requirements and daily CHO guidelines. Fluctuations in protein intake throughout the day were noted and may influence training adaptations (i.e., muscle protein synthesis and recovery).

Physical Fitness and Body Composition of Youth Referees in Invasion Games.

BACKGROUND: Referees' activity can be an instrument for training students with an impact on health-related physical fitness (PF). This study aimed to investigate the differences in PF and body composition between students without sports practice (G1), students with regular sports practice (G2), and student referees in team invasion games (G3). METHODS: This study followed a cross-sectional design. The sample comprised 45 male students between 14 and 20 years old (16.40 ± 1.85). Three groups (G1, G2, and G3) of 15 participants each were selected. PF was assessed by a 20 m shuttle run, change-of-direction test, and standing long jump. Body composition was determined by body mass index (BMI; kg/m2) and the percentage of body fat (%BF) predicted by skinfold. RESULTS: After controlling for age as a covariate, the block of variables used to characterize PF was statistically different between sports practice groups favoring student referees (p < 0.001; r = 0.26). Similar results were achieved for body composition (i.e., BMI and %BF) (p < 0.001; r = 0.17). However, when the dependent variables were evaluated separately, there were only differences between groups in %BF (p = 0.007; r = 0.21). Student referees had statistically significantly lower values than the remaining groups. CONCLUSION: Refereeing activity benefits PF related to health and performance, including body composition. This study confirms the benefits related to health in children and adolescents who are involved in refereeing activity.