Football Training Research Articles

The insufficiency of recreational exercises in improving cardiovascular fitness: an investigation of ventricular systolic and diastolic parameters and left atrial mechanical functions

AimThis study aimed to compare the left ventricular (LV) systolic and diastolic parameters and left atrial (LA) mechanical functions of individuals engaging in recreational sports and resistance exercises on a weekly basis.MethodsA total of 43 male amateur athletes were included in this study, of which 24 performed resistance exercises (REs) (29.70 ± 8.74 year, weight: 81.70 ± 12.64 kg, height: 176.05 ± 7.73 cm, BMI: 27.64 ± 4.97 kg/m2), and 19 participated in recreational football training and were included in the recreational sports group (31.73 ± 6.82 year, weight: 86.00 ± 18.52 kg, height: 178.62 ± 4.95 cm, BMI: 25.55 ± 3.42 kg/m2). The exercises were standardized according to the weekly exercise frequency and volume. After recording the participants’ demographic information, the LV systolic and diastolic parameters and LA mechanical functions were measured using echocardiography (ECHO) and Tissue Doppler Imaging.ResultsSignificant differences were observed in various cardiac parameters between the recreational sports group (REG) and resistance exercise Group (RSG). Specifically, the left ventricular (LV) diastolic diameter, LV end diastolic volume index (LVEDVi), and stroke volume index were notably higher in the REG compared to the RSG (t = 2.804, p = .010, effect size (ES) = 2.10; t = 3.174, p = .003, ES = 0.98; t = 3.36, p = .002, ES = 1.02, respectively). Notably, the RSG exhibited higher values for LV mass index (LVMi) and isovolumic relaxation time (IVRT) than the REG (t = 2.843, p = .007, ES = 0.87; t = 2.517, p = .016, ES = 0.76) in terms of LV systolic and diastolic parameters. Regarding left atrial (LA) mechanics, the REG demonstrated increased LA total emptying volume index, LA maximum volume index, LA volume before systole measured at the onset of the p-wave index, and conduit volume index compared to RSG (t = 2.419, p = .020, ES = 0.75; t = 2.669, p = .011, ES = 0.81; t = 2.111, p = .041, ES = 0.64; t = 2.757, p = .009, ES = 0.84, respectively).ConclusionOur study revealed significant variations in LV and LA functions between REG and RSG. Our data suggest that REs led to substantial cardiac remodeling, altering myocardial structure and function. In contrast, the effect of recreational exercise on cardiac adaptation was less pronounced than that of resistance exercise. Consequently, we propose that individuals engaging in recreational exercise should consider modalities that impose higher cardiovascular demand for more effective cardiac conditioning.

Alleviating anxiety disorders in college students through football training and competition system reform

BackgroundCollege students frequently grapple with anxiety stemming from academic and employment pressures, often leading to the development of anxiety disorders over time. Football training, as a team sport, not only enhances physical fitness but also aids in anxiety reduction during physical activities. Nonetheless, existing football training and competition systems face challenges that undermine their effectiveness in treating anxiety. This study investigates the potential of reforming the football training and competition system as an intervention to address anxiety disorders in college students.Subjects and MethodsA study was conducted on 67 college students with anxiety disorders, who were divided into an observation group and a control group. The control group adopts traditional methods, while the observation group adopts the reformed football training and competition system for sports intervention. After the experiment, SPSS 20.0 software was used for statistical analysis.ResultsAfter the observation group experiment, the somatization score of college students was 17.10, the anxiety score was 15.25, and the interpersonal sensitivity score was 14.31. The neuroticism score was 11.66, which was significantly better than the pre-experimental score. Meanwhile, after the experimental intervention, 13.4% of 9 people had anxiety factor scores greater than 2. Significantly lower than the 40.3% before the experiment.ConclusionsThe reform of the football training and competition system proves highly effective as an intervention strategy for addressing anxiety disorders among college students.

A flexible pressure sensor based on electrospun fiber for gait monitoring in football training

After football players receive high-intensity training, they often have muscle injuries. The development of a stretchable wearable sport sensor with high sensing performance will effectively solve this problem. In this work, we develop a flexible and stretchable pressure sensor based on graphene/ESTANE TPU nanofiber electrodes and the [C2OHMIM]Cl/ESTANE TPU nanofiber electrolyte. Owing to the microporous structure of electrospun film, the pressure sensor has the advantages of good air permeability and skin compatibility. The working mechanism of the pressure sensor is based on the supercapacitance sensing mechanism, which brings a wide detection range, high repeatability, high sensitivity, and fast response. Besides, the sensor installed at the knee can perform gait analysis, such as walking and running with the ball, in football. Furthermore, the sensor array developed can monitor the pressure distribution at the knee in football in real time. This research will promote the application of intelligent sports equipment in football training.

Functional Prototype Design for a Programmable Equipment in Personalized Football Training

AbstractAssembly and testing are the last stages in the design phase to obtain proof of concept for a certain product. Although it is time and cost consuming, assembly fit and test are crucial for the future development of any complex product, unveiling potential consequences in the future product life cycle. The current paper addresses the main assembly stages, testing strategies, feedback implementation, and redesign decisions involved in the development of a programmable equipment in personalized football training. Demountable subassemblies are used for the manufacture of the final prototype, encouraging interchangeability of parts, and modularity of the final product. Coupling, gear, key, and bearing assemblies are mainly used to physically obtain the programmable equipment prototype. Since some components are bespoke and are 3D printed specifically for this product, fit tests are undertaken to ensure proper functioning of all mechanical and electronic components. Software and electronic testing are also done to both calibrate and ensure proper code functioning. Optimization of the prototype is implemented in all three main systems that make up the personalized football training equipment: mechanical, electronic, and software. The optimized functional prototype of the equipment will be subjected to endurance tests in order to evaluate the life expectancy of individual components, subassemblies, and, finally, of the general product.

Bilateral Asymmetry and the Relationship Between Unilateral Isokinetic Strength and Balance Performance in Male Adolescent Football Players

Muscle strength and balance ability have been related to injury prevention and game actions performance in football. The aims of this study are twofold: (1) to examine bilateral asymmetries in isokinetic strength and balance assessments, and (2) to evaluate the relationship between muscle strength and balance measures. Eighty-eight male adolescent football players were assessed for body composition (InBody 770), isokinetic strength (Biodex System 4 Pro Dynamometer), and balance performance (Biodex Balance System). Paired samples t-tests were conducted to determine bilateral differences in strength and balance. Pearson correlations and multiple linear regression analyses evaluated the relationship between strength and balance. No significant bilateral strength differences were observed in knee flexors (KF) and knee extensors (KE) peak torque (PT) scores. No bilateral differences were found for balance measures, except in the lateromedial stability index, which was better while performing with the preferred leg (p ≤ 0.01; d = 0.29). Significant correlations were found between KE PT and balance tasks (p ≤ 0.01). KF and KE PT shared between 18 and 22% of the common variance in the overall stability index in the non-preferred and preferred leg, respectively. Monitoring strategies of bilateral asymmetries may be crucial to enhance performance in tasks underpinned by unilateral movements, such as changes of direction and sprints, and to identify players at risk of injury. Adopting these strategies during the early stages of football training might be crucial for players’ long-term development.

Exercise Cardiac Load and Autonomic Nervous System Recovery during In-Season Training: The Impact on Speed Deterioration in American Football Athletes.

Fully restoring autonomic nervous system (ANS) function is paramount for peak sports performance. Training programs failing to provide sufficient recovery, especially during the in-season, may negatively affect performance. This study aimed to evaluate the influence of the physiological workload of collegiate football training on ANS recovery and function during the in-season. Football athletes recruited from a D1 college in the southeastern US were prospectively followed during their 13-week "in-season". Athletes wore armband monitors equipped with ECG and inertial movement capabilities that measured exercise cardiac load (ECL; total heartbeats) and maximum running speed during and baseline heart rate (HR), HR variability (HRV) 24 h post-training. These metrics represented physiological load (ECL = HR·Duration), ANS function, and recovery, respectively. Linear regression models evaluated the associations between ECL, baseline HR, HRV, and maximum running speed. Athletes (n = 30) were 20.2 ± 1.5 years, mostly non-Hispanic Black (80.0%). Negative associations were observed between acute and cumulative exposures of ECLs and running speed (β = -0.11 ± 0.00, p < 0.0000 and β = -0.15 ± 0.04, p < 0.0000, respectively). Similarly, negative associations were found between baseline HR and running speed (β = -0.45 ± 0.12, 95% CI: -0.70, -0.19; p = 0.001). HRV metrics were positively associated with running speed: (SDNN: β = 0.32 ± 0.09, p < 0.03 and rMSSD: β = 0.35 ± 0.11, p < 0.02). Our study demonstrated that exposure to high ECLs, both acutely and cumulatively, may negatively influence maximum running speed, which may manifest in a deteriorating ANS. Further research should continue identifying optimal training: recovery ratios during off-, pre-, and in-season phases.

O.4.1-7 Recreational football training increases leg-extensor force production at high velocities in 55- to 70-year-old adults

Abstract Purpose Ageing coincides with a blunted ability to produce force at moderate to high velocities. Therefore, improving muscle power, especially at moderate to high velocities, is a crucial target for exercise interventions in middle-aged and older adults. We investigated the effects of 10 weeks of recreational football training on the leg-extensor force-velocity (F-V) profile in 55- to 70-year-old adults. Simultaneous effects on functional capacity, body composition and endurance exercise capacity were examined. In addition, feasibility and the physical demands of the training program were tracked. Methods Forty participants (age 63.5 ± 3.9 years) were randomized in a football training (FOOT, n = 20) and a control (CON, n = 20) group. FOOT performed 45-min to 1-h of football training sessions with small-sided games (SSG’s) twice a week. Pre and post intervention, leg-extensor F-V profile (maximal power (Pmax), maximal force (F0), maximal velocity (V0), the slope divided by F0 (SFV/F0)), functional capacity, body composition and endurance exercise capacity were measured. Results Results revealed an increase over time for Pmax (ptime = 0.009), but no interaction effect (pint = 0.221). A greater increase in V0 and in SFV/F0 was apparent in FOOT compared to CON (pint = 0.043 and pint = 0.065). No interaction effect was found for F0 (pint = 0.922). Three-step stair ascent power, 10m fast walk, body fat percentage and running speed at 2mM lactate improved significantly more in FOOT than in CON (all pint &amp;lt; 0.1). The SSG’s elicited intense muscular actions and high average heart rates of 85.7% of maximal heart rate. Despite the high training load, participants perceived the sessions as very enjoyable and feasible. Conclusions The present study emphasized that recreational football can be used as a feasible, enjoyable and effective training tool in middle-aged to older adults for improving force production at high velocities. This improvement is translated into a better performance on functional capacity tests that rely on high execution velocity. In addition, broad-spectrum health benefits can be realized with only 2 hours of training per week. Funding E. Van Roie was supported by the Research Foundation Flanders, Belgium (senior postdoctoral fellowship 12Z5720N).

Own goal or home run? Exploring the implementation of virtual reality training in football and baseball organisations

PurposeDespite the perceived benefits of implementing virtual reality (VR) training in elite sport, arguably the most important element – the perceptions of practitioners – has been largely understudied. Therefore, the present study aims to explore practitioners' perceptions of VR training in elite football and baseball, with a focus on the important factors, obstacles, perceived knowledge and practical use of the technology.Design/methodology/approachA quantitative approach measuring practitioner perceptions via an online questionnaire was adopted. Football respondents (n = 25) represented practitioners from major football leagues across the world, and baseball respondents (n = 15) represented practitioners from Major League Baseball.FindingsBoth football and baseball respondents reported that the most important factor for implementation of VR training was improvement in on-field performance (technical and tactical); whilst cost was viewed as the biggest obstacle. Both football and baseball respondents also noted that the most likely group to receive VR training would be injured and rehabilitating athletes. Mann–Whitney U tests revealed that football respondents perceived coach (p = 0.02) and executive approval (p < 0.001) as significantly greater obstacles than baseball respondents.Originality/valueThis research provides novel and invaluable information for stakeholders within VR regarding what the elite organisations of different sports perceive as the most important factors for implementation, as well as greatest obstacles preventing use. This information should guide future development and marketing of VR training systems in sport.

The Big Story of a “Small” Football Club: Gümüşlükspor as an Alternative Model Experience for Turkey

This article argues that counter-hegemony, which is at the heart of sports activism, is not just an action but also the construction of alternative institutional structures. For this purpose, it investigates the practices of an amateur football club and discusses the structural problems of the Turkish amateur football league. The data, collected during a 6-month field study, were interpreted from a critical perspective, using a dialectical dialogue method to apply the theory of hegemony in sports by applying Antonio Gramsci’s concept of the “organic intellectual.” Consequently, this sports club has provided socialization and free football training for children while creating an alternative football culture with local characteristics that are opposed to class and gender inequalities and to homophobic attitudes common in sport.

Mengembangkan Kebugaran Fisik Dengan Mengadakan Pelatihan Sepak Bola Di Desa Ciklapa Tahun 2023

Thematic KKN contains a series of interdisciplinary integrative activities which are packaged strategically to solve problems which are carried out together with the community by playing the community as the main actor and involving other related stakeholders. In this case, students act as motivators in the process of solving problems and building or developing society. The work program that has been prepared is football training. In the soccer training work program, the objects are children around the post and several hamlets. Football training is carried out 4 times in 4 weeks

The Effects of Football and Volleyball Training on Neurotic Values of 30-40 Age Group Male Police Officers

Backraound: In this study, it was aimed to determine the effect of football and volleyball training on the neurotic values of 30-40 age group male police officers and to contribute to the studies and literature in this field.The universe of the research consists of 45 male police officers aged 30-40 working in Altınordu district of Ordu province in 2019. &#x0D; Material and Method: The research is in quasi-experimental research design model. "Eysenck Personality Inventory" was used in the study. Statistical analysis of the data was made with the SPSS 21 program. In the study, the compliance of the data to the normal distribution was tested by using the Shapiro-Wilk test and it was observed that the applied test was suitable for the groups. In comparing the means of more than two groups, one-way analysis of variance (Anova) was used for unrelated samples, and one-way analysis of variance was used for repeated measures in more than two comparisons of a group.&#x0D; Results: When the general evaluation is made according to the research results; In the first week of the Eysenck Personality Inventory, it was observed that the volleyball group had the lowest score, while the score of the control group was higher than the volleyball group, and the score of the football group was higher than the control group. In the fourth and eighth week applications of the post-training test, the lowest score was found in the volleyball group, the football group got higher scores than the volleyball group, and the control group got higher scores than the football group. While the overall mean scores of the groups decreased in the volleyball and football groups, fluctuations were observed in the scores of the control group. Considering the neurotic score averages of the test, the volleyball group got the lowest value according to the test applied in the first week, while the football and the control group had a high value with equal values. While the neurotic value averages of the volleyball and football groups decreased after the trainings applied, the neurotic score average of the control group first increased and then decreased. In the study, it was determined that sports positively affect the neuroticism values of individuals. &#x0D; Conclusion: According to the results obtained with this study, it has been revealed that doing sports is one of the most effective options for people who work under high stress, especially for police officers, to get rid of the stored negative energy and to have a more positive perspective on life.The results of the study were evaluated with similar studies, and recommendations were made based on the findings.

A study on the influence of FIFA 11+ practice on knee proprioception and dynamic balance ability of young campus football players

To study the effect of FIFA 11 + warm-up on knee proprioception and dynamic balance of adolescent football players. 30 young school football players were randomly divided into two groups: FIFA 11 + training group and routine warm-up training group. The dominant leg of all athletes is the right leg. FIFA 11 + training was arranged once a day in the pre training warm-up stage of FIFA 11 + group， while the control group was given regular warm-up exercise with the team. Two groups of experimental data were collected and recorded. The closer the feeling (active and passive) of the knee joint was to 135 degrees， the better the result was. In the dynamic balance test of the knee joint (YBT)， the scores of the non supporting leg in front were recorded as a， the scores of the non supporting leg in the rear inner side were recorded as PM， the scores of the non supporting leg in the rear outer side were recorded as PL， and the comprehensive scores of YBT were recorded as ybt-cs， The higher the score of analysis and comparison results， the better the balance and stability function. The difference of the above recorded data was analyzed by independent sample t-test， and the significance level a was 0.05. After FIFA After 11 + training， there were significant differences in the comparison values of proprioception (active and passive) between the knee joint groups (P (0.05) compared with the control group， the difference was significant. After FIFA 11 + warm-up exercise， it can significantly improve the knee proprioception and dynamic balance ability of young school football players. Therefore， coaches should be encouraged to use FIFA 11 + warm-up activities in the future football training match warm-up activities.

The Effects of Nitrate Supplementation on Performance as a Function of Habitual Dietary Intake of Nitrates: A Randomized Controlled Trial of Elite Football Players.

Nitrates are an effective ergogenic supplement; however, the effects of nitrate supplements based on habitual dietary nitrate intake through diet alone are not well understood. We aimed to assess this in a group of 15 highly trained football players from Slovenian football's First Division. Participants underwent two separate Cooper performance tests either with nitrate supplementation (400 mg nitrates) or placebo while having their nutrition assessed for nitrate intake, as well as energy and macronutrient intake. Nitrate supplementation had a statistically significant positive effect on performance if baseline dietary nitrate intake was below 300 mg (p = 0.0104) in both the placebo and intervention groups. No effects of nitrate supplementation when baseline dietary nitrate intake was higher than 300 mg in the placebo group could be concluded due to the small sample size. Nitrate supplementation did not have a significant effect on perceived exertion. The daily nitrate intake of the participants was measured at 165 mg, with the majority of nitrates coming from nitrate-rich vegetables.

The effects of high-velocity hamstring muscle training on injury prevention in football players.

Background: Explosive and fast body movements, sprints, jumps and quick changes of direction, which are characteristic of the football training, place considerable strain on the hamstring muscles. Due to the high occurrence of hamstring injuries, new preventive strategies are required that focus on high-velocity training. The purpose was to assess the effectiveness of high-velocity elastic-band training in reducing the occurrence of hamstring injuries in football players. Methods: Male football players from 15 teams (n = 319) playing in national competitions participated in this study. The players were involved in a 5-week exercise period in either the intervention group (INT) or the control group (CON), with a follow-up period of ∼4months where hamstring injuries and exposure time were recorded. The INT group had two to three sessions per week of elastic-band training with low-load, high-velocity leg curls while lying prone; the CON group performed self-paced football-specific drills. Results: The incidence rate of hamstring injuries was 6.5% in the INT group (8 out of 123 players) and 9.2% in the CON group (18 out of 196 players). Although the INT group showed almost 1/3 reduction in hamstring injury incidence compared to the CON group, the difference was not statistically significant (p > 0.05). Moreover, no differences (p > 0.05, odds ratio [OR] = trivial-to-small) in distribution between the groups were found in hamstring injury characteristics (leg dominance and mechanism) except for the distribution of injuries that occurred during matches or training (p = 0.036; OR = 6.14, moderate). Conclusion: The program of high-velocity elastic-band training did not prove to be effective in preventing hamstring muscle injuries in football players despite displaying some positive indications that could be considering when creating injury prevention programs.

Longitudinal cardiac remodeling in collegiate American football players as assessed by echocardiography during their collegiate career.

Studies on the longitudinal effects of intense physical training on cardiac remodeling are limited, especially in American collegiate football players. College-level American football training will result in remodeling in a pattern consistent of a sport with moderate static and dynamic demands with increases in both wall and chamber sizes. We studied 85 American collegiate football players who underwent transthoracic echocardiogram (TTE) for asymptomatic or mild COVID-19-related illness and compared the changes in echo dimensions to their preparticipation screening TTE. Pre- and posttraining variables were compared using a paired t-test for normally distributed variables. Mean age was 19 years ± 1 and 61% of athletes were Black. Mean follow-up between TTEs was 21 ± 13 months. There was an increase in left atrial volume index (26.4 ± 5.5 to 32.8 ± 8.4 mL/m2 , p < .001), LV end diastolic diameter (5.13 ± 0.4 to 5.27 ± 0.4 cm, p = .003), basal RV diameter (3.28 ± 0.7 to 3.83 ± 0.5 cm, p = <.001), LV mass index (86.7 ± 15.3 to 90.1 ± 15.3, p = .015), and aortic root diameter (3.1 ± 0.4 to 3.2 ± 0.3 cm, p = .03) from pre- to posttraining, with a slightly greater magnitude in athletes with >2 years of training. Presence of left atrial enlargement (≥35 mL/m2 ) increased from 2.9% to 29% pre- to postparticipation in athletes with >2 years training. No significant changes in wall thickness, diastolic function, or right ventricular systolic function were observed. American football players college-level training was associated with increases in left and right ventricular chamber sizes, left atrial size, and aortic root diameter.

Basic Technique Skill Practice Model Filanesia-Based Football

Purpose: This research aims to develop a Filanesia-based basic football technique training model for the soccer skill development phase aged 10-13 years with learning media in the form of interactive multimedia. Theoretical Framework: This choice is not just a subjective choice but a choice that is also based on valid theoretical arguments. The perchloric form of exercise must be abandoned to be able to produce intelligent players. Method: This study uses the Research and Development approach from Borg and Gall, which aims to find answers to the problem of basic football technical skill models based on Filanesia. After going through the entire series, the basic physio-based football technique training model effectively improves players' passing, dribbling, and shooting skills. This is based on the results of effectiveness tests on the new model with the old model. Result and Conclusion: The results of the effectiveness test data were obtained after treating the research sample for 16 meetings. Based on the results of needs analysis, expert validation, field trials, effectiveness tests and discussion of research and development results on the product development of the filanesia-based basic football technique training model for ages 10-13 years. Research Implications: This developed skill training model is effective for improving the essential technical skills of football aged 10-13 years. Originality/Value: The following conclusions can be drawn. The filanesia-based basic football technique skill training model in the skill development phase aged 10-13 years can be developed and applied in football training.

Effective playing time affects technical-tactical and physical parameters in football.

Effective playing time has been debated as a topic of major concern in football. Thus, the current experimental study aimed to investigate the effects of effective playing time on technical-tactical and physical match parameters in football. One hundred and seventy-nine male highly trained football players (aged 27.9 ± 5.1 years) from twelve teams performed two different match-play conditions: 45 min of match-play without stopping the chronometer (T45), and 30 min of match-play by stopping the chronometer every time the ball was out-of-play (T30). T30 presented a significantly higher total time (49:30 vs. 45:00 min; p = <.001; ES = 0.76), effective playing time (28:70 vs. 26:80 min; p = <.001; ES = 0.62), and stopped time (20:60 vs. 18:20 min; p = 0.003; ES = 0.38) compared to T45. Total ball possession (54.4% vs. 45.6%; p = 0.002) and 1/3 ball possession (55.3% vs. 44.7%; p = 0.018) was higher in T30 condition when compared to T45. Regarding match external load, total distance covered (4,899 vs. 4,481 m; p = <.001; ES = 0.71), moderate-speed running (607 vs. 557 m; p = 0.002; ES = 0.26) and high-speed running (202 vs. 170 m; p = <.001; ES = 0.33), high-speed activities (284 vs. 245 m; p = 0.003; ES = 0.24), accelerations (27 vs. 24; p = <.001; ES = 0.32), and decelerations (31 vs. 28; p = 0.005; ES = 0.26) were higher in T30 compared to T45. In conclusion, these findings suggest that higher effective playing time may affect technical-tactical and physical parameters during football games.

Resultant equations for training load monitoring during a standard microcycle in sub-elite youth football: a principal components approach.

Applying data-reduction techniques to extract meaningful information from electronic performance and tracking systems (EPTS) has become a hot topic in football training load (TL) monitoring. The aim of this study was to reduce the dimensionality of the internal and external load measures, by a principal component approach, to describe and explain the resultant equations for TL monitoring during a standard in-season microcycle in sub-elite youth football. Additionally, it is intended to identify the most representative measure for each principal component. A principal component analysis (PCA) was conducted with a Monte Carlo parallel analysis and VariMax rotation to extract baseline characteristics, external TL, heart rate (HR)-based measures and perceived exertion. Training data were collected from sixty sub-elite young football players during a 6-week training period using 18 Hz global positioning system (GPS) with inertial sensors, 1 Hz short-range telemetry system, total quality recovery (TQR) and rating of perceived exertion (RPE). Five principal components accounted for 68.7% of the total variance explained in the training data. Resultant equations from PCA was subdivided into: (1) explosiveness, accelerations and impacts (27.4%); (2) high-speed running (16.2%); (3) HR-based measures (10.0%); (4) baseline characteristics (8.3%); and (5) average running velocity (6.7%). Considering the highest factor in each principal component, decelerations (PCA 1), sprint distance (PCA 2), average HR (PCA 3), chronological age (PCA 4) and maximal speed (PCA 5) are the conditional dimension to be considered in TL monitoring during a standard microcycle in sub-elite youth football players. Current research provides the first composite equations to extract the most representative components during a standard in-season microcycle in sub-elite youth football players. Futures research should expand the resultant equations within training days, by considering other well-being measures, technical-tactical skills and match-related contextual factors.

Retracted: Walking Position Data in Football Training Based on Embedded Action Recognition System

Retracted: Walking Position Data in Football Training Based on Embedded Action Recognition System

A drum structure triboelectric nanogenerator based on PS/MXene for football training monitoring

Recently, flexible multifunctional sensors have attracted widespread attention from around the world. Here, we propose a novel PS/MXene-based triboelectric nanogenerator (PM-TENG), which has a drum structure design. Through comparative experiments, the optimal ratio of polystyrene (PS) materials was explored. The PS film and nylon film form the triboelectric materials, and copper foil acts as the conducive electrode. From the results, the open-circuit voltage (Voc) and short-circuit current (Isc) of the PM-TENG based on 35 mg/ml content of PS can reach 141 V and 5.9 µA, respectively. In addition, when the resistance value of the external load is 50 MΩ, the PM-TENG exhibits a maximum output power of 123 µW. Due to its excellent flexibility, the PM-TENG can be installed on the shoulders, neck, wrist, elbow, knee, and ankle to achieve all-round motion monitoring of football players. This research can promote the application of TENG sensors in the football monitoring field.