Examining tactical sprint actions and distribution among playing positions attending to match status in soccer: Implications for specific training.

The study aimed to analyze the tactical sprint actions performed by Spanish professional soccer players, considering their playing positions and the match status at the time of each action. Thirty-two Spanish male professional soccer players from a LaLiga Spanish Second Division (LaLiga SmarthBank) team participated in this study. Actions above 85% of the players' maximum velocity during 42 official matches were collected by an optical tracking system ChyronHego® and were synchronized using Mediacoach software (LaLiga, Madrid, Spain). Then, actios were analyzed trough an observation instrument designed to assess the type of tactical action performed by players. Central defenders (CD) and wide defenders (WD) were mainly involved in recovery runs. Central midfielders (CM) also frequently performed recovery runs and pressing actions. Wide midfielders (WM) were often engaged in runs in behind/penetrate actions, while forwards (F) had a diverse range of sprint actions, including pressing, runs in behind/penetrate, and breaking into the box. It was observed that F performed fewer chase actions than expected. On the other hand, CD, WD, and CM engaged in a greater number of recovery run actions than expected. CD also performed more close down/interception actions than expected, while CM, WM, and F performed fewer close down/interception actions than expected. When their team was losing, WM performed more recovery run actions than expected. CM made more runs with the ball when their team was winning CD showed a higher frequency of breaks into the box when their team was winning. These findings provide valuable information regarding the tactical aspects of sprinting in soccer, facilitating the design of specific training tasks that not only address the physical demands associated with each playing position but also considering the tactical context in which sprints occur.

Influence of the External Workload on Calf Muscle Strain Injuries in Professional Football Players: A Pilot Study.

BACKGROUND: The influence of external workload variables on the development of calf muscle strainsin football players has not been previously explored. HYPOTHESIS: Overloaded players would have an increased risk of calf muscle strain injury. STUDY DESIGN: Prospective observational study. LEVEL OF EVIDENCE: Level 4. METHODS: A total of 41 professional football players from 1 team were monitored for 2 consecutive seasons. Total distance covered (TD), and distances covered at high-intensity running, high sprint running, low (LACC) and high (HACC) acceleration, low (LDEC) and high (HDEC) deceleration, and at high metabolic load distance (HMLD) were monitored with GPS units. Accumulated players' external workload in the week before injury was compared with the weekly mean value of the 6 weeks before injury occurred for each player. RESULTS: Ten players (24.3%) suffered 16 calf muscle strain injuries (3.1 injuries per 1000 hours of match play; 0.5 injuries per 1000 hours of training exposure). Players with a calf muscle injury were older (p = 0.03), with higher body weight (p = 0.01) and height (p = 0.03). Injured players displayed substantially higher total training volume (p < 0.01), TD (p < 0.01), LACC (p < 0.01), LDEC (p < 0.01), HACC (p < 0.01), HDEC (p < 0.01), and HMLD (p = 0.03) in the week before injury, in comparison with the mean values of these variables in the 6 weeks before injury. CONCLUSION: A week with a higher-than-habitual external workload might increase the risk of calf muscle strain injury in professional football players. Calf muscle injuries were preceded by a week with unusually high workloads associated with accelerating and decelerating distances and higher training volumes. CLINICAL RELEVANCE: Monitoring external workload indicators may be helpful in determine players with a higher risk of calf muscle strain injury due to excessive workload during training/competition.

Force Production and Electromyographic Activity during Different Flywheel Deadlift Exercises.

This study aimed to characterize and compare force production and muscle activity during four flywheel deadlift exercises (bilateral [Bi] vs. unilateral [Uni]) with different loading conditions (vertical [Ver] vs. horizontal [Hor]). Twenty-three team-sport athletes underwent assessments for exercise kinetics (hand-grip force), along with surface electromyography (sEMG) of the proximal (BFProx) and medial biceps femoris (BFMed), semitendinosus (ST), and gluteus medius (GM). Mean and peak force were highest (p < 0.001) in Bi + Ver compared with Bi + Hor, Uni + Ver, and Uni + Hor. Although no significant differences were observed between Bi + Hor and Uni + Ver, both variants showed higher (p < 0.001) average force and peak eccentric force when compared with Uni + Hor. The presence of eccentric overload was only observed in the vertically loaded variants. Bi + Ver and Uni + Ver showed higher (p < 0.05) sEMG levels in BFProx and BFMed compared with the Uni + Hor variant. In addition, Uni + Ver registered the largest GM and ST sEMG values. In conclusion, the vertical variants of the flywheel deadlift exercise led to higher muscle force production and sEMG compared with their horizontal counterparts. Both Bi + Ver and Uni + Ver may be effective in promoting an increase in hamstring muscles activity and muscle force at long muscle length, while the Uni + Ver variant may be more effective in promoting GM and ST involvement.

The influence of match status on the conditional characteristics of tactical sprint actions in professional soccer players.

This study aimed to analyse the influence of the match status on the conditional characteristics of tactical sprint actions among Spanish professional soccer players, considering playing positions. Thirty-two Spanish male professional soccer players from a LaLiga Spanish Second Division (LaLiga SmarthBank) team participated in this study. Actions above 85% of the players' maximum velocity were analysed based on their tactical purpose. These findings provide valuable information regarding the tactical aspects of sprinting in soccer, emphasizing the influence of playing positions and match status on the distribution of tactical sprint actions. No effects of match status were observed for any game phase. However, when tactical actions were individually studied, it was observed that the maximum velocity in Chase actions was higher when the team was winning, while in Press actions, the maximum velocity was higher when the team was losing and in in Run in behind/Penetrate, the maximum velocity was higher in drawing situations compared to losing situations. No effects of match status on the distance covered during sprinting were observed, and regarding duration, significant differences were only observed in Recovery run actions. In addition, the influence of match status is higher when playing positions are considered, although the within playing positions analysis revealed significant differences only in CM players. These findings provide valuable information for the design of specific training drills considering playing positions, suggesting the need to analyse the previous match in order to structure the training load of the microcycle in a comprehensive manner.

PHYTOCHROME A controls the DNA damage response and cell death tolerance within the Arabidopsis root meristem.

The DNA damage response avoids mutations into dividing cells. Here, we analysed the role of photoreceptors on the restriction of root growth imposed by genotoxic agents and its relationship with cell viability and performance of meristems. Comparison of root growth of Arabidopsis WT, phyA-211, phyB-9, and phyA-211phyB-9 double mutants unveiled a critical role for phytochrome A (PhyA) in protecting roots from genotoxic stress, regeneration and cell replenishment in the meristematic zone. PhyA was located on primary root tips, where it influences genes related to the repair of DNA, including ERF115 and RAD51. Interestingly, phyA-211 mutants treated with zeocin failed to induce the expression of the repressor of cell cycle MYB3R3, which correlated with expression of the mitotic cyclin CycB1, suggesting that PhyA is required for safeguarding the DNA integrity during cell division. Moreover, the growth of the primary roots of PhyA downstream component HY5 and root growth analyses in darkness suggest that cell viability and DNA damage responses within root meristems may act independently from light and photomorphogenesis. These data support novel roles for PhyA as a key player for stem cell niche maintenance and DNA damage responses, which are critical for proper root growth.

Current Guidelines for the Implementation of Flywheel Resistance Training Technology in Sports: A Consensus Statement.

BACKGROUND: Flywheel resistance training has become more integrated within resistance training programs in a variety of sports due to the neuromuscular, strength, and task-specific enhancements reported with this training. OBJECTIVE: This paper aimed to present the consensus reached by internationally recognized experts during a meeting on current definitions and guidelines for the implementation of flywheel resistance training technology in sports. METHODS: Nineteen experts from different countries took part in the consensus process; 16 of them were present at the consensus meeting (18 May 2023) while three submitted their recommendations by e-mail. Prior to the meeting, evidence summaries were developed relating to areas of priority. This paper discusses the available evidence and consensus process from which recommendations were made regarding the appropriate use of flywheel resistance training technology in sports. The process to gain consensus had five steps: (1) performing a systematic review of systematic reviews, (2) updating the most recent umbrella review published on this topic, (3) first round discussion among a sample of the research group included in this consensus statement, (4) selection of research group members-process of the consensus meeting and formulation of the recommendations, and (5) the consensus process. The systematic analysis of the literature was performed to select the most up-to-date review papers available on the topic, which resulted in nine articles; their methodological quality was assessed according to AMSTAR 2 (Assessing the Methodological Quality of Systematic Review 2) and GRADE (Grading Recommendations Assessment Development and Evaluation). Statements and recommendations scoring 7-9 were considered appropriate. RESULTS: The recommendations were based on the evidence summary and researchers' expertise; the consensus statement included three statements and seven recommendations for the use of flywheel resistance training technology. These statements and recommendations were anonymously voted on and qualitatively analyzed. The three statements reported a score ranging from 8.1 to 8.8, and therefore, all statements included in this consensus were considered appropriate. The recommendations (1-7) had a score ranging from 7.7 to 8.6, and therefore, all recommendations were considered appropriate. CONCLUSIONS: Because of the consensus achieved among the experts in this project, it is suggested that practitioners and researchers should adopt the guidelines reported in this consensus statement regarding the use of flywheel resistance technology in sports.

Validation of ActiGraph and Fitbit in the assessment of energy expenditure in Huntington's disease.

BACKGROUND: Consumer and research activity monitors have become popular because of their ability to quantify energy expenditure (EE) in free-living conditions. However, the accuracy of activity trackers in determining EE in people with Huntington's Disease (HD) is unknown. RESEARCH QUESTION: Can the ActiGraph wGT3X-B or the Fitbit Charge 4 accurately measure energy expenditure during physical activity, in people with HD compared to Indirect Calorimetry (IC) (Medisoft Ergo Card)? METHODS: We conducted a cross-sectional, observational study with fourteen participants with mild-moderate HD (mean age 55.7 ± 11.4 years). All participants wore an ActiGraph and Fitbit during an incremental test, running on a treadmill at 3.2 km/h and 5.2 km/h for three minutes at each speed. We analysed and compared the accuracy of EE estimates obtained by Fitbit and ActiGraph against the EE estimates obtained by a metabolic cart, using with Intra-class correlation (ICC), Bland-Altman analysis and correlation tests. RESULTS: A significant correlation and a moderate reliability was found between ActiGraph and IC for the incremental test (r = 0.667)(ICC=0.633). There was a significant correlation between Fitbit and IC during the incremental test (r = 0.701), but the reliability was poor at all tested speeds in the treadmill walk. Fitbit significantly overestimated EE, and ActiGraph underestimated EE compared to IC, but ActiGraph estimates were more accurate than Fitbit in all tests. SIGNIFICANCE: Compared to IC, Fitbit Charge 4 and ActiGraph wGT3X-BT have reduced accuracy in estimating EE at slower walking speeds. These findings highlight the need for population-specific algorithms and validation of activity trackers.

Ligament Injuries in Professional Male Handball Players: A 6-Year Longitudinal Study.

Handball is a sport that involves high-intensity actions throughout the game, such as sprints, jumps, landings, and high-speed, repeated throws. This, along with competitive and tactical factors, congested schedules, and the need to maintain a high level of performance throughout the season, contributes to a high injury rate. This study aimed to analyse ligament injuries in a professional handball team over six consecutive seasons. A total of 68 elite male Spanish handball players participated, with 54 time-loss injuries (i.e., injuries involving at least one day of absence) observed during this study period. Ligament injury information was recorded following the International Olympic Committee consensus statement. The overall incidence was 0.89 ligament injuries per 1000 h of exposure. Additionally, a higher incidence and burden of ligament injuries was observed during match-play compared to training. Most ligament injuries were classified as minor or moderate (i.e., 79.63% of the total), and 46.29% were reinjuries. A significantly higher incidence of ligament injuries was suffered in the lower limbs compared to the upper limbs (0.81 vs. 0.08 ligament injuries per 1000 h; p < 0.001). Specifically, the highest incidence was observed in the anterior talofibular ligament of the ankle (0.57 injuries per 1000 h of exposure), while the greatest burden was related to the anterior cruciate ligament (24.08 absence days per 1000 h of exposure). This study provides an overview of ligament injuries among professional handball players, highlighting the need to implement strategies with positive effects during competition (e.g., specific activation strategies or training programmes based on strength and balance) and to reduce injury recurrences.

Effects of Contextual Variables on Match Load in a Professional Soccer Team Attending to the Different Season Periods.

This study aimed to analyze the effects of contextual variables (i.e., match location and match outcome) and season periods on match load (i.e., internal and external load) in professional Brazilian soccer players. Thirty-six professional players from the same soccer team participated in this study. The season was split into four phases: matches 1-16 (i.e., Phase 1 = P1); matches 17-32 (i.e., Phase 2 = P2); matches 33-48, (i.e., Phase 3 = P3); matches 49-65 (i.e., Phase 4 = P4). Considering match outcome, when the team wins, Cognitive load, Emotional load, and Affective load were significantly higher in away vs. home matches (p < 0.05). Considering season phases, in P3, Mental Fatigue was significantly higher in drawing than in losing matches (p < 0.05). Additionally, considering the match outcome, when the team lost, Total Distance (TD)/min and TD > 19 km·h-1/min were significantly lower in P1 than P2 (p < 0.001), P3 (p < 0.001), and P4 (p < 0.001). These results suggest to strength and conditioning coaches the need to consider the outcome and location of the previous game when planning the week, as well as the phase of the season they are in to reduce fatigue and injury risk.

Longitudinal Relationships Between Physical Fitness With Physical Self-Concept and Self-Esteem in Adolescents.

Purpose: Physical fitness has shown to be positively related with young people's general mental health, mainly due to the changes in body composition derived from a regular sportive practice. Thus, the aim of this study was three-fold: 1) to analyze the relationship between physical fitness with the mental health status assessed as physical self-concept and self-esteem, 2) to study whether self-esteem offers longitudinal relationships with physical fitness three months after the first assessment, and 3) to know the most implicated variables of physical fitness in mental health variables. Method: A total of 1441 adolescents aged 12 to 19 years (mean=14.52; standard deviation=1.96 years), being the 49.5 % of them girls, from 4 high schools in Andalusia, Spain, participated in the study. The EUROFIT battery test was administered to the participants, as well as some questionaries to assess the physical self-concept and the self-steem. Physical tests and self-concept were assessed in an only temporal point, while self-esteem was analyzed longitudinally. Results: The results obtained indicated that physical self-concept was related to physical fitness, while self-esteem was especially related to the Course Navette test. Conclusions: These results suggest that having great levels of physical fitness, especially related to aerobic endurance, may help to have higher levels of physical self-concept and self-esteem as components of mental health in Spanish adolescents.

The Inclusion of Preplanned and Random and Unanticipated/Unexpected Events During Strength Training Improves the Ability to Repeat High-Intensity Efforts Under Uncertainty.

PURPOSE: To compare the effects of unilateral flywheel training (FT), using a rotational conical pulley, including multidirectional movements with either preplanned or random unanticipated/unexpected executions on functional performance in football players. METHODS: A total of 32 young male football players were randomly assigned to an FT program including preplanned unilateral multidirectional movements (PTG, n = 11), an FT executing the same unilateral movements through random (ie, right or left leg) unanticipated (ie, verbal or visual cue) or unexpected (ie, moment where the cue was provided) situations (UTG, n = 11), or a control group (n = 10) that followed their football training routine. FT consisted of 1 set × 5-12 repetitions of 4 exercises performed once a week for 10 weeks. Intermittent endurance performance, repeated unilateral and bilateral jumping ability, change-of-direction (COD) ability, linear sprint velocity, preplanned repeated-sprint ability (RSA), and uncertainty RSA (RSA-RANDOM) were assessed preintervention and postintervention. RESULTS: Significant improvements were found in RSA-RANDOM performance (P < .05, effect size [ES] range: UTG [1.83-2.16], PTG [0.69-0.73]) and COD (P < .05, ES: UTG = 1.34, PTG = 0.98]) in both training groups. Furthermore, significant improvements were also found in intermittent endurance performance (P = .016, ES = 0.37) and sprinting (P = .006, ES = 0.45) in UTG. No changes in any variable were found in the control group. No significant between-groups differences (P > .05) were reported between UTG and PTG, while differences were observed to the control group in unilateral jumping ability, COD, and RSA-RANDOM for UTG, and in RSA-RANDOM for PTG. CONCLUSIONS: A 10-week unilateral FT improved RSA-RANDOM and COD ability in youth football players, so both preplanned and unexpected situations should be included on strength training.

Increased game frequency period crossing Ramadan intermittent fasting decreases fat mass, sleep duration, and recovery in male professional basketball players.

Background: Increased basketball game frequency may affect athlete performances, especially during Ramadan intermittent fasting (RIF). The objective of the present investigation was to assess the impacts of increased game frequency periods crossing the RIF on body composition, sleep habits, indices of well-being, recovery state, and dietary intake in professional male basketball players. Methods: Twenty-eight professional basketball players participated in this study and were divided into increased-games-frequency (INCR) or normal-games-frequency (NORM) groups. INCR trained four times and completed two games per week, whereas NORM completed only one game per week. During the first and fourth weeks of RIF, the following variables were assessed: internal load (weekly session rating of perceived exertion (s-RPE), heartrate (HR)), dietary intake, body composition, sleep quality (PSQI survey), well-being indices questionnaire (sleep, fatigue, stress, delayed onset of muscle soreness (DOMS)), and recovery state with the Total Quality Recovery (TQR) questionnaire. Results: The internal load significantly increased after 4 weeks of RIF in INCR compared to NORM (p < 0.001). Significant decrease of TQR, sleep duration, and a significant increase of DOMS only for INCR (26.93%, p < 0.001, ES = 0.48, small; 33.83%, p < 0.001, ES = 0.40, small; 161.17%, p < 0.001, ES = 0.32, small; respectively). Significant group × time interaction was observed for body mass (p = 0.006, ES = 0.46, small) and body fat percentage (p = 0.025, ES = 0.33, small), with INCR having a greater decrease in all these values. Conclusion: Increased game frequency period crossing RIF decreases fat mass, sleep duration, and recovery in professional basketball players, which may consequently affect performance and health.

Is a Maximal Strength-Training Program Effective on Physical Fitness, Injury Incidence, and Injury Burden in Semi-Professional Soccer Players? A Randomized Controlled Trial.

The aims of the study were to analyze the effects of a 12-week maximal strength- training program on injury incidence, injury burden, and physical fitness in semi-professional soccer players and to compare the perceived exertion load and well-being state between injured and non-injured soccer players. Twenty semi-professional male soccer players participated in this study. Participants were randomly allocated to an experimental group (EG, n = 10 players), who performed a maximal strength-training program, or to a control group (CG, n = 10 players), who only performed their regular soccer training. Physical fitness was measured at baseline and after the training program. In addition, the injury incidence, burden, training/match load, and the state of well-being of the players were recorded. The EG showed significant improvements in vertical jumps, change in direction ability, linear sprints, repeated sprint ability, isometric strength (p < 0.003; effect size = 1.78-11.86), and quadriceps-hamstring imbalance in both legs (p < 0.001; effect size = 2.37-3.71) in comparison to the CG. In addition, the EG players showed a significantly (p < 0.05) lower injury burden (p < 0.001, relative risk = 5.05, 95% confidence interval = 3.27-7.79). This study demonstrated the beneficial effects of a 12-week maximal strength-training program on physical fitness attributes and injury burden in semi-professional soccer players.

Relationship between Physical Fitness and Cyberbullying Patterns (Cybervictimization and Cyberperpetration) in Spanish Adolescents.

(1) Background: Cyberbullying is a growing problem among adolescents, and deeper knowledge of this phenomenon could facilitate the implementation of adequate prevention and intervention strategies. Therefore, the aim of this study was to analyze the relationships between victimization and aggression patterns in cyberbullying and physical fitness levels in Spanish adolescents. (2) Methods: A total of 741 adolescents aged 12 to 19 years from two high schools in Andalusia, Spain (mean = 14.52 ± 1.96 years; 50.9% girls, 49.1% boys) participated in the study. The participants underwent the EUROFIT battery test and completed the Spanish version of the European Cyberbullying Intervention Project Questionnaire (ECIPQ) scale. T-test, bivariate correlations and a linear regression analysis were used for statistical analysis. (3) Results: The study results indicated positive relationships between cyberbullying patterns, especially cybervictimization, and age, as well as several physical fitness measures, including BMI, sit-ups, sit-and-reach, and handgrip tests. On the other hand, cyberperpetration was positively related only to age and the specific grip strength test. Further statistical analysis revealed that cybervictimization was primarily influenced by age, while cyberperpetration was mainly influenced by age and performance in a functional test (sit-and-reach). (4) Conclusions: Cyberbullying roles, both as victims and aggressors, may not be strongly influenced by isolated physical fitness factors. Thus, in order to reach a more comprehensive understanding and better explanations of individual involvement in cyberbullying behavior, future studies should analyze psychological and social factors along with the variables considered in this study.

Effect of coaches' interpersonal style on young athletes' individual resilience and team adherence intention: a season-long investigation.

BACKGROUND: In the sports context, coaches must be able to improve their players physically, psychologically, and socially. Hence, a fundamental part of this process is the athlete's individual resilience (IR). METHODS: Three hundred and fifteen youth team-sport players (boys: n = 283; Mage = 16.02, SD = 0.56; and girls: n = 32; Mage = 15.92, SD = 0.62) completed the measures of coach's interpersonal style, individual resilience, perceived performance, and team adherence intention (intention to remain on the same team the following year) twice (Time 1: mid-season; Time 2: end-season). Structural equation modeling was used to test the relationships between variables. RESULTS: The results showed that coach support was positively related to IR (p < 0.001) and, in turn, IR to individual (p < 0.01) and team performance (p < 0.05) at Time 1, and to individual performance (p < 0.001) and team adherence intention at Time 2 (p < 0.01). In addition, team performance at Time 2 was positively related to team adherence intention (p < 0.001). Finally, a mediating effect of IR was observed between interpersonal coaching style, individual and team performance, and team adherence intention. CONCLUSIONS: These results show the importance of a supportive interpersonal coaching style to foster athletes' levels of resilience, which could have positive consequences in performance (individual and team) and team adherence intention.

Pseudomonas aeruginosa LasI-dependent plant growth promotion requires the host nitrate transceptor AtNRT1.1/CHL1 and the nitrate reductases NIA1 and NIA2.

MAIN CONCLUSION: In P. aeruginosa, mutation of the gene encoding N-acyl-L-homoserine lactone synthase LasI drives defense and plant growth promotion, and this latter trait requires adequate nitrate nutrition. Cross-kingdom communication with bacteria is crucial for plant growth and productivity. Here, we show a strong induction of genes for nitrate uptake and assimilation in Arabidopsis seedlings co-cultivated with P. aeruginosa WT (PAO1) or ΔlasI mutants defective on the synthesis of the quorum-sensing signaling molecule N-(3-oxododecanoyl)-L-homoserine lactone. Along with differential induction of defense-related genes, the change from plant growth repression to growth promotion upon bacterial QS disruption, correlated with upregulation of the dual-affinity nitrate transceptor CHL1/AtNRT1/NPF6.3 and the nitrate reductases NIA1 and NIA2. CHL1-GUS was induced in Arabidopsis primary root tips after transfer onto P. aeruginosa ΔlasI streaks at low and high N availability, whereas this bacterium required high concentrations of nitrogen to potentiate root and shoot biomass production and to improve root branching. Arabidopsis chl1-5 and chl1-12 mutants and double mutants in NIA1 and NIA2 nitrate reductases showed compromised growth under low nitrogen availability and failed to mount an effective growth promotion and root branching response even at high NH4NO3. WT P. aeruginosa PAO1 and P. aeruginosa ΔlasI mutant promoted the accumulation of nitric oxide (NO) in roots of both the WT and nia1nia2 double mutants, whereas NO donors SNP or SNAP did not improve growth or root branching in nia1nia2 double mutants with or without bacterial cocultivation. Thus, inoculation of Arabidopsis roots with P. aeruginosa drives gene expression for improved nitrogen acquisition and this macronutrient is critical for the plant growth-promoting effects upon disruption of the LasI quorum-sensing system.

The effect of three different pre-match warm-up structures on male professional soccer players' physical fitness.

Background: Optimizing the soccer players' match preparation is one of the most relevant concerns of coaches for strength and conditioning training. Thus, the aim of this study was to analyze the effects of three pre-match warm-up structures on the physical condition of male professional soccer players. Materials & Methods: Seventeen male professional soccer players (age: 20.9 ± 2.4 years) of one Tunisian Professional Soccer League team participated in this study. Players performed three times a typical pre-match warm-up (WU) [aerobic phase (AE); neuromuscular phase (NM); velocity phase (VL); and ball-specific phase (BS) variating the order of the included phases/exercises: WU1 (AE + BS + NM + VL); WU2 (AE + NM + VL + BS); and WU3 (AE + VL + BS + NM). After each warm-up phase, players completed the following physical fitness tests: linear sprint test, countermovement jump test, 15-m ball dribbling agility test and ball shooting test. Additionally, the rate of perceived exertion (RPE) was registered after each warm-up. Results: The results indicated significant differences between WU1 and WU3, with better results in the ball shooting test and RPE in WU3. In addition, there were no significant differences in the other variables and between other warm-up structures. These findings could be of great interest for coaches to the strength and conditioning coaches for professional soccer teams in order to improve the players physical performance and perceived exertion.

Multi-joint isometric measurement for the evidence-based assessment of upper limb strength impairment in wheelchair athletes with different health conditions: a preliminary study.

The present study presents a novel specific multi-joint isometric test to assess upper limb strength impairment for evidence-based classification in wheelchair sports. Sixteen wheelchair athletes participated in this study and were classified according to their type of physical impairment and health condition as follows: athletes with neurological impairment (ANI, n = 5) and athletes with impaired muscle power (IMP, n = 11). In addition, six non-disabled participants formed a control group (CG, n = 6). All the participants performed the isometric propulsion strength test (IPST), evaluating pushing and pulling actions, and two wheelchair performance tests. Excellent relative intra-session reliability scores were obtained for strength values for the ANI, IMP and CG groups (0.90 < ICC < 0.99) and absolute reproducibility showed acceptable scores of SEM (< 9.52%) for IPST pushing action. The ANI had significantly lower scores in strength and wheelchair performance than the IMP and the CG, while no differences were found between the IMP and the non-disabled participants. In addition, no correlations were found for wheelchair athletes between the isometric upper limb strength measure and wheelchair performance. Our findings suggest that the IPST is a valid test for strength measurement in upper limb impairment wheelchair athletes with different health conditions, which must be used in combination with a performance test to obtain a holistic assessment of this population.