Search Results (132)

This study analyses the physical performance variables involved in different training tasks aimed at replicating the worst-case scenarios (WCSs) observed during official matches in professional football, with a focus on playing positions and occurrences within a 1 min period. Data were collected from 188 training sessions and 42 matches of a Spanish Second Division team during the 2021/2022 season. All data were reported on a per-player basis. GPS tracking devices were used to record physical variables such as total distance, high-speed running (HSR), sprints, accelerations, decelerations, and high metabolic load distance (HMLD). Players were grouped according to their match positions: central defenders, wide players, midfielders and forwards. The results showed that none of the training tasks fully replicated the physical demands of match play. However, task TYPEs 11 (Large-Sided Games) and 9 (small-sided games with orientation and transition) were the closest to match demands, particularly in terms of accelerations and decelerations. Although differences were observed across all variables, the most pronounced discrepancies were observed in sprint and HSR variables, where training tasksfailed to reach 60% of match demands. These findings highlight the need to design more specific drills that simulate the intensity of WCS, allowing for more accurate weekly training load planning. This study offers valuable contributions for optimising performance and reducing injury risk in professional footballers during the competitive period. Full article

Background: This study aimed to compare the immediate effects of small-sided games (SSGs) and running-based high-intensity interval training (HIITrb) on serum brain-derived neurotrophic factor (BDNF) levels, cognitive performance, and enjoyment in young, male soccer players. Methods: Twenty-four soccer players [age: 19.2 ± 0.8 years] completed one session each of four-a-side SSG or HIITrb in a randomized, counterbalanced, and crossover design, with a one-week washout period. Blood samples and Trail Making Tests (TMTs) A and B were measured before and after exercise. Heart rate (HR) was monitored throughout the games, and ratings of perceived exertion (RPE) and enjoyment were collected at the end of the measurements. Results: The results show no significant effects of time (p > 0.775), group (p > 0.276) or time × group interaction (p > 0.199) on BDNF levels. For TMT-A, the time effect (p = 0.866) and group effect (p = 0.057) were not significant; however, the time × group interaction was significant (p < 0.019), indicating a superior performance in the SSG compared to HIITrb. In the TMT-B, significant effects were observed for both time (p < 0.001) and group (p < 0.001), while the time × group interaction effect was not statistically significant (p > 0.061). Furthermore, enjoyment levels did not differ significantly between conditions (p = 0.976). Conclusions: These findings suggest that four-a-side SSG may enhance processing speed compared to HIITrb without changes in serum BDNF levels. Coaches may consider using 4v4 SSG formats in early training sessions or warm-ups to stimulate processing speed and mental readiness in young soccer players. Full article

With the increasing popularity of electric vehicles (EVs) through purchase subsidy (PS) policies, the personal carbon tax (PCT) policy has been adopted by some countries due to its characteristics of restraining the diffusion of fuel vehicles (FVs) from the consumer side. This paper constructs a three-stage game model consisting of government, manufacturers, and consumers to investigate the impact of basic utility valuation heterogeneity differences on the optimal decisions and to compare the implementation effects of two policies. The results are as follows. First, conventional wisdom suggests that EV consumer surplus under PS policy will exceed that under PCT policy. Surprisingly, our results show that when the basic utility valuation difference is small, the EV consumer surplus under PCT policy exceeds that under PS policy. Second, for manufacturers, it is interesting to note that the sustained impact of PCT policy on promoting the diffusion of the EV market and the profit of the EV manufacturer is related to the basic utility valuation heterogeneity difference. However, compared with PS policy, the implementation of PCT policy has a better restraining effect on the diffusion of the FV market, effectively reducing the demand for FV and the profit of FV manufacturers. Finally, contrary to the common belief that increasing subsidies or raising carbon taxes can increase overall social welfare, this paper shows that subsidies and carbon taxes have a dual impact on overall social welfare, and only when their positive effects outweigh the negative ones can such policies become effective ways of promoting industrial transformation. Full article

Interventions based on improving athletes’ adaptive capacity to game environment conditions have been widely developed in sports science. The objective of this study was to systematically review the scientific literature on interventions and applications, from an ecological perspective, for the tactical performance of volleyball players. A systematic search was conducted in five electronic scientific databases in accordance with PRISMA guidelines: Web of Science (WOS), PubMed (Medline), Scopus, SportDiscus and Google Scholar. A total of eight studies met the inclusion criteria, all published after 2014. The risk of bias and main characteristics of the articles in different contexts were assessed. Particular attention was paid to recording data related to the characteristics of manipulation or the timing of the intervention. The results showed that these approaches influenced tactical variables in volleyball game situations. In this sense, short-session interventions with small-sided games and modifications of structural elements aid athletes’ self-regulation in different environments. Furthermore, results show that this approach allows for improvements in individual and collective tactical behavior. Based on the data analyzed, we recommend the use of ecological tasks, based on representative and modified practices that promote player adaptation, as a methodological tool in the volleyball training process. Full article

Background: Hypertension is a significant public health issue, particularly in individuals with comorbidities such as COPD and T2DM, which exacerbate cardiovascular risk and impair quality of life. While physical activity is an effective intervention for reducing blood pressure and improving health markers, conventional therapies often lack the social and psychological benefits of team sports. Team sports conducted as small-sided games provide a dynamic, engaging approach that combines physical, social, and psychological advantages, making them particularly suitable for individuals with complex chronic conditions. Methods: This non-randomized intervention study involved twenty-eight hypertensive patients, including 16 individuals with type 2 diabetes mellitus (T2DM) (8 men and 8 women) and 12 with chronic obstructive pulmonary disease (COPD) (7 men and 5 women). Participants engaged in a training program, primarily consisting of team sports (floorball and cone ball), at a municipal health center twice a week for 12 weeks. Results: The intervention led to a significant reduction in systolic blood pressure (p = 0.006), with patients with COPD and T2DM showing decreases of 9.6 ± 12.7 mmHg and 12.4 ± 19.0 mmHg, respectively. Additionally, the time to complete the 2.45 m “Up and Go” test improved significantly (p < 0.001), with both COPD (p = 0.011) and T2DM (p = 0.005) patients demonstrating notable improvements. However, no significant changes were observed in body mass, chair stand performance, five-repetition sit-to-stand test, handgrip strength, or diastolic blood pressure following the intervention. Conclusions: Team sports training conducted in a municipality health center is effective in lowering blood pressure and improving functional capacity in hypertensive COPD and T2DM patients. Full article

Football is a complex game that requires combined technical, tactical, and psychological skills. The effect of training methods on players is crucial to improve their performance significantly. Different training methods can improve certain performance; however, the effect of combined training methodologies has not been sufficiently investigated. This study aimed to investigate the differential effects of small-sided games (SSGs), strength training (ST), and a combined training model (CTM) on the physical performance of soccer players. In this study, we analyzed 60 players in three groups. Two groups were trained independently with two single-training methods, small-sided games and a strength training model, and one group was trained independently with a double-training method, a combination of single-training methods. Before each training session, each group was given theoretical education specific to the training program they would perform. Eighteen physical measurements of the players were obtained using sensitive devices before and after they were completed. Four tree-based machine learning models, decision tree, random forest, gradient boosting, and extreme gradient boosting, were applied to solve the complex pattern of training strategies using the measurements. Extensive and comparative experiments were conducted to distinguish the groups of players. The distinction between the initial and final measurements was analyzed separately, and the extreme gradient boosting model achieved 0.73–0.80 and 1.00 accuracy for initial and final tests by outperforming other models. A superior model, XGBoost, was used to analyze the effective decisive factors that improved after the training sessions. The results showed that players in the double-training group demonstrated significantly greater improvements in skill performance compared to both single-training groups. In contrast, the skill gains observed in the single-training groups were modest and partially overlapping, indicating limited differentiation between them. These results suggest that integrated training programs may offer more comprehensive benefits and can inform evidence-based decision-making for coaches seeking to optimize physical development in soccer players. Full article

Training drills are fundamental to the development of athletes across various sports disciplines, including basketball. This review examines the multifaceted factors influencing both the external and internal workload of drills during training sessions. The results of this review show that factors such as the type of drills utilized, space constraints, the number of players involved, adjustments to game rules, work-to-rest ratios, modifications to roles or tactical scenarios, the level of coach involvement, and the type of opposition all significantly impact drill workload. Research highlights that no isolated variable can fully capture the complexity or demands of an activity within a drill; instead, it is the interplay of different variables that determines the nature and focus of the drill. All the factors mentioned above should all be carefully considered to effectively tailor the physical demands and orientation of the drill. A comprehensive understanding of these factors can help coaches and athletes optimize training regimens to achieve desired performance outcomes while minimizing the risk of overtraining or injury. By synthesizing current research, this review provides valuable insights into the complex interplay of factors shaping drill workload in basketball training sessions. Full article

Elite football players face increasing physical and tactical demands due to rising match schedules emphasizing the need for effective load monitoring strategies to optimize performance and reduce injury risk. This study integrates fitness and fatigue indices derived from a machine learning approach to develop a performance score based on Banister’s fitness–fatigue model. Data were collected over two seasons (2022/23 and 2023/24) from 23 elite players of an Italian professional team. Fitness was assessed via heart rate collected during small-sided games, while fatigue was evaluated through PlayerLoad recorded during training sessions; both were normalized using z-scores. Match outcomes, including physical (e.g., total distance, high-sprint distance) and tactical metrics (e.g., field tilt, territorial domination), were analyzed in relation to performance conditions (optimal, intermediate, poor). Results revealed that players in the optimal performance condition exhibited significantly higher second-half physical outputs, including total distance (z-TD_2ndHalf: p < 0.05, ES = 0.29) and distance covered at >14.4 km/h (z-D14.4_2ndHalf: p < 0.01, ES = 0.52), alongside improved match tactical parameters as territorial domination (%TDO_2ndHalf: p < 0.01, r = 0.431). This study underscores the utility of invisible monitoring in football, providing actionable insights for weekly training periodization. This research establishes a foundation for integrating data-driven strategies to enhance physical and tactical performance in professional football. Full article

China’s power generation system has undergone reforms, leading to a competitive electricity market where independent producers participate through competitive bidding. With the rise of low-carbon policies, producers must optimize bidding strategies while reducing carbon emissions, creating complex interactions with local governments. Evolutionary game theory (EGT) is well-suited to analyze these dynamics. This study begins by summarizing the fundamental concepts of electricity trading markets, including transaction models, bidding mechanisms, and carbon reduction strategies. Existing research on the application of evolutionary game theory in power markets is reviewed, with a focus on theoretical constructs such as evolutionary stable strategies and replicator dynamics. Based on this foundation, the study conducts a detailed mathematical analysis of symmetric and asymmetric two-group evolutionary game models in general market scenarios. Building upon these models, a three-group evolutionary game framework is developed to analyze interactions within power producer groups and between producers and regulators under low-carbon mechanisms. A core innovation of this study is the incorporation of a case study based on China’s electricity market, which examines the evolutionary dynamics between local governments and power producers regarding carbon reduction strategies. This includes analyzing how regulatory incentives, market-clearing prices, and demand-side factors influence producers’ bidding and emission reduction behaviors. The study also provides a detailed analysis of the bidding strategies for small, medium, and large power producers, revealing the significant impact of carbon pricing and market-clearing prices on strategic decision-making. Specifically, the study finds that small producers tend to adopt more conservative bidding strategies, aligning closely with market-clearing prices, while large producers take advantage of economies of scale, adjusting their strategies at higher capacities. The study explores the conditions under which carbon emission reduction strategies achieve stable equilibrium, as well as the implications of these equilibria for both market efficiency and environmental sustainability. The study reveals that integrating carbon reduction strategies into power market dynamics significantly impacts bidding behaviors and long-term market stability, especially under the influence of governmental penalties and incentives. The findings provide actionable insights for both power producers and policymakers, contributing to the advancement of low-carbon market theories and supporting the global transition to sustainable energy systems. Full article

Background: Understanding the balance between intensity and volume during training and competition is crucial for optimizing players’ performance and recovery in professional soccer. While worst-case scenarios (WCSs) are commonly used to assess peak match demands, little is known about how the time spent within WCS thresholds varies across congested and non-congested periods, especially when considering differences in playing time. This study examines the time spent at different percentages of WCSs during congested and non-congested periods for players with lower and higher playing times throughout training sessions and matches. Methods: Data were collected from a professional soccer team across a congested and non-congested match period. Twenty players were divided into two groups based on playing time: the top 10 playing times (PT 1–10) and the bottom 10 playing times (PT 11–20). WCS thresholds for total distance (TD) and the distance covered above 20 km·h⁻¹ (D20) were quantified in 10% increments, starting from 50% and increasing up to >100%. The time spent at each threshold was compared between periods and groups for the integrated soccer exercises performed during all training sessions. Repeated measures of ANOVA were used to analyze differences between playing time groups and periods. Results: During training, players spent significantly more time within the 50–90% WCS TD and WCS D20 thresholds during non-congested periods compared to congested periods (p < 0.05). However, no significant differences were observed in the time spent for >90% of the WCSs between periods (p > 0.05). Both PT 1–10 and PT 11–20 groups exhibited similar patterns of WCS achievement, with small effect sizes observed for a few indicators. Conclusion: Coaches should design training sessions that replicate or exceed match demands, particularly during non-congested periods. Future strategies should integrate larger-sided games with longer durations and dissociated contents to better individualize and optimize training loads, especially for non-starters. Full article

Adjusting the design of small-sided games and selecting the appropriate format can significantly enhance training outcomes and player development in soccer. The aim of the study was to compare the effects of intermittent small-sided games (ISSG) and continuous small-sided games (CSSG) on athletic performance metrics in male soccer players. This pilot study was conducted using a parallel group pre-test and post-test design, with 16 male youth soccer players randomly assigned to two groups: the ISSG group (n = 8, Mean age = 16.50 ± 0.53 years) and the CSSG group (n = 8, Mean age = 16.63 ± 0.52 years), ensuring a balance in pre-test performance and playing positions. The ISSG protocol began with 4 min sets in week one, progressively increasing to 7 min by week four, with 2 min rest intervals. The CSSG protocol involved continuous play, starting at 16 min and progressing to 28 min over the same period. Players underwent pre- and post-tests, with a 4-week training period. Performance metrics assessed included body composition, a 30 m sprint test, agility, horizontal jump, aerobic and anaerobic capacity, and static balance. Training intensity was monitored using the CR-10 Borg Rating of Perceived Exertion scale throughout the training period. Both groups exhibited improvements in horizontal jump, agility, aerobic and anaerobic power, and static balance, with no significant between-group differences. Sprint performance did not significantly improve in either group. The CSSG group reported higher RPE values and experienced a reduction in body mass index. Our findings demonstrate that both ISSG and CSSG resulted in similar improvements in athletic performance metrics in male youth soccer players. Coaches and practitioners can choose the most appropriate training method based on specific objectives, session duration, and player fatigue levels, thereby optimizing training outcomes. Full article

Background: Carbohydrate mouth rinsing (CHOmr), a nutritional intervention for delaying fatigue and meeting the energy demands of soccer, and the motivational strategy of coach encouragement (CE) are widely recognized as effective approaches for enhancing athletic performance in soccer. Objectives: This study aimed to compare the effects of CHOmr + CE, CHOmr, and CE on heart rate (HR) and kinematic profiles during four-a-side small-sided soccer games (SSGs). Methods: Twenty-four young soccer players (age: 17.2 ± 0.8 years) played six bouts of four-a-side SSGs with CHOmr + CE, CHOmr, or CE at 3-day intervals in a randomized, single-blinded, placebo-controlled, or crossover study design. The HR and kinematic responses were continuously recorded during all games. Results: There were no statistically significant differences between the groups in peak heart rate (HR_peak) (p ≥ 0.05, F = 0.326, p = 0.723, η² = 0.014) and mean heart rate (HR_mean) (p ≥ 0.05, F = 0.845, p = 0.436, η² = 0.035). No significant differences were found for distances in Zone 1 (p ≥ 0.05, F = 1.21, p = 0.306, η² = 0.050), Zone 4 (p ≥ 0.05, F = 0.310, p = 0.735, η² = 0.013), Zone 5 (p ≥ 0.05, F = 1.02, p = 0.368, η² = 0.042), or Zone 6 (p ≥ 0.05, F = 0.161, p = 0.211, η² = 0.055), nor acceleration (p ≥ 0.05, F = 0.208, p = 0.137, η² = 0.083) and deceleration (p ≥ 0.05, F = 0.790, p = 0.460, η² = 0.033). Similarly, although no significant differences were observed in the distance in Zone 3 (p ≥ 0.05, F = 3.12, p = 0.054, η² = 0.119) or repeated sprint distance (p ≥ 0.05, F = 2.96, p = 0.062, η² = 0.114), the CHOmr +CE group exhibited higher average values for these variables. However, a statistically significant difference was observed in the distance covered in Zone 2 (p ≤ 0.05, F = 3.89, p = 0.028, η² = 0.145), with the CHOmr +CE group performing better, as confirmed by the post-hoc analyses. Conclusions: Although our findings indicate that CE alone may influence kinematic profiles during SSGs, similar to CHOmr or its combination with CE, further research should explore the underlying mechanisms and potential contextual factors influencing these outcomes. Therefore, we suggest that coaches prefer CE because it is easy to implement. Full article

Background: Sprint performance is crucial in rugby, impacting offensive and defensive actions. Despite increasing research on team sports, specific sprint training guidelines for rugby remain limited. This review evaluates the effectiveness of various training methods to improve sprint performance in semi-professional and professional players. Objectives: To identify and assess the most effective training methodologies for improving rugby sprint performance and provide evidence-based recommendations for coaches. Methods: A systematic review adhering to PRISMA guidelines was conducted across PubMed, Web of Science, and SPORTDiscus, including studies published before November 2024. Eligible studies focused on Rugby Union, Rugby League, or Rugby Sevens players undergoing resistance-based or sprint-specific training for at least four weeks. Exclusion criteria included amateur players, athletes under 16, or interventions using advanced technologies. Methodological quality was assessed using the PEDro scale. Results: Twenty-six studies involving 644 rugby players were analysed. Training programmes ranged from 4 to 18 weeks (average: 8 weeks) and were categorised into resistance training, small-sided games, and sprint-specific methods. Resistance training combined with plyometrics and agility drills achieved the most significant sprint improvements. Small-sided games enhanced sprint performance by simulating game-like scenarios, while resisted sprint training showed notable results for short-distance acceleration but limited maximum speed gains. Conclusions: Rugby sprint performance improves through periodised training protocols incorporating resistance exercises, plyometrics, and sport-specific drills. Coaches should use small-sided games and resisted sprint training to target short-distance acceleration and agility. Further research should examine the long-term effects of these methods and their influence on match performance. Full article

The aim of this study was to evaluate the effect of 11 additional soccer training sessions among youth soccer players according to their performance in a skill course. A total of 90 participants, aged 9 to 12, were randomly assigned to either an intervention group (IG) (n = 54) or a control group (CG) (n = 36) and have validated data. The trainings focused upon enhancing ball mastery and decision-making and included a combination of one vs. one situations and small-sided games (SSGs). Pre- and post-tests measured passing and dribbling skills through a skill course. The best time with additional time penalties for each dribbling and passing error was used for further analysis. An independent t-test revealed no significant differences in improvement between the two groups. However, paired t-tests revealed significant improvements for both the IG and the CG from pre- to post-test (7.9 and 3.9 s, respectively). Furthermore, no significant differences in the development of track time, cone touches, or passing errors between the groups were detected. These findings suggest that soccer players aged 9 to 12 improve their performance in a skill course through increased familiarity with the course and natural development of technical skills based on participation in soccer training and recreational soccer play. We argue that the lack of significant differences between the groups’ performances can be attributed to the short duration and few sessions of the intervention, and a somehow low similarity between the skill course and the activities in the sessions. Full article

The purpose of this study was to compare the internal and external load in continuous and intermittent small-sided games (SSG) formats. Eight semi-professional soccer players participated in the study, and they completed three protocols: (a) I-intermittent SSG protocol (Int-I, 4 sets of 4 min with a 3 min recovery); (b) Continuous SSG protocol (Con, 2 sets of 8 min with a 3 min recovery); (c) II-SSG protocol (Int-II, 4 sets of 4 min, where each set includes 1 min of exercise with varying recovery periods (10, 20, 30 s), with a 3 min recovery period between sets). A one-way analysis of variance (ANOVA) was used to analyze the dependent variables, with significance determined at p < 0.05. The three protocols differed in total distance covered and in distance covered at speeds >19 km/h, with the Int-II protocol resulting in the greatest distance covered (p < 0.05). Additionally, players in the Con protocol exercised at a higher percentage of their maximum heart rate (%HRmax) (p < 0.05), while the highest RPE value was observed in the Int-I interval protocol (p < 0.05). The external load experienced by players in intermittent SSG protocols is higher, while internal load (%HRmax) remains relatively low. This effect is especially notable in the new intermittent exercise model proposed in this study, which incorporates progressively increasing recovery times within each exercise set. Coaches can use this model to increase players’ external load without causing a heightened perception of fatigue. Full article