Elite Football Players Research Articles

Time-loss and recurrence rates after lateral ankle ligament sprains in male elite football players: summary of a systematic review and meta-analysis

A literature search was conducted to systematically review and meta-analyse time-loss and recurrence rates of lateral ankle sprains (LAS) in male professional football players. Six electronic databases were screened separately for time-loss and recurrence rates after lateral ankle sprains in elite football players. A total of 13 (recurrence) and 12 (time-loss) studies met the previously defined inclusion criteria. The total sample size of the recurrence studies was 36.201 participants (44.404 overall initial injuries, 7944 initial ankle sprain (AS) injuries, 1193 recurrent AS injuries). 16.442 professional football players (4893 initial AS injuries, 748 recurrent AS injuries) were subsequently meta-analysed. A recurrence rate of 17.11% (95% CI: 13.31-20.92%; df=12; Q=19.53; I2=38.57%) was determined based on the random-effects model. A total of 7736 participants were part of the time-loss studies (35.888 total injuries, 4848 total ankle injuries; 3370 AS injuries). Out of the 7736 participants, 7337 participants met the inclusion criteria with a total of 3346 AS injuries. The average time-loss was 15 days (weighted mean: 15.92, median: 14.95, min: 9.55; max: 52.9). A priori, we determined considerable heterogeneity (CI: 18.15-22.08; df=11; Q=158; I2=93%). There is an average time-loss of 15 days per LAS and a recurrence rate of 17%. LAS is one of the most common types of injury with high recurrence rates in professional football players. The high recurrence rates and long-term consequences show the necessity for research in the field of LAS in elite football. However, heterogeneous data lead to difficulties regarding the aspect of comparability.

Association between ACE and ACTN3 genes polymorphisms and athletic performance in elite and sub-elite Chinese youth male football players.

Previous studies have shown controversial relationships between ACE I/D and ACTN3 R577x polymorphisms and athletic performance. Therefore, the aim of this study was to assess athletic performance indicators of Chinese youth male football players with different ACE and ACTN3 gene profiles. This study recruited 73 elite (26 13-year-olds, 28 14-year-olds, and 19 15-year-olds) and 69 sub-elite (37 13-year-olds, 19 14-year-olds, and 13 15-year-olds) and 107 controls (63 13-year-olds, and 44 14-year olds aged 13-15 years, all participants were of Chinese Han origin. We measured height, body mass, thigh circumference, speed, explosive power, repeat sprints ability, and aerobic endurance in elite and sub-elite players. We used single nucleotide polymorphism technology to detect controls elite and sub-elite players' ACE and ACTN3 genotypes, Chi-squared (χ 2) tests were employed to test for Hardy-Weinberg equilibrium. χ 2 tests were also used to observe the association between the genotype distribution and allele frequencies between controls and elite and sub-elite players. The differences in parameters between the groups were analyzed using one-way analysis of variance and a Bonferroni's post-hoc test, with statistical significance set at p≤0.05. (1) The genotype distribution of the ACE I/D and ACTN3 R577x polymorphisms in controls, elite and sub-elite football players were consistent with Hardy-Weinberg equilibrium, except for the ACE genotype distribution of sub-elite players. (2) The RR and DD genotypes were significantly different between elite and sub-elite players (p = 0.024 and p = 0.02, respectively). (3) Elite players were more likely to have the RR genotype and less likely to have the DD genotype compared with sub-elite players. (4) Both elite and sub-elite RR players' Yo-yo intermittent recovery level 1 (YYIR1) running distance was significantly longer than that of RX players (p = 0.05 and p = 0.025, respectively). However, there was no significantly different in YYIR1 running distance between elite and sub-elite RR players. (5) Elite XX players' VO2 max was significantly higher than that of RX and sub-elite players. These results indicate that ACE I/D and ACTN3 R577x polymorphisms are not associated with muscle power in Chinese elite and sub-elite players. The XX genotype of ACTN3 is associated with the aerobic endurance of elite players.

"I hardly have a problem […] I have my period quite rarely too": Female football players' and their coaches' perceptions of barriers to communication on menstrual cycle.

Symptoms related to the menstrual cycle (MC) affect the performance level and health of female athletes in various ways. Previous research has reported MC symptoms such as pain, mood disturbance, reduced coordination and competition distraction as well as diminished performance levels and an increased injury risk among female elite athletes. Despite this, the coach-athlete communication related to the female hormonal cycle is limited. The aim of the present study was to explore the perceptions of MC communication in a group of junior elite football players and their male coaches in a case study of one youth football team in a specific club in Norway. The study used a qualitative approach with semi-structured interviews. In total, 8 female junior elite players (aged 16-20) from a Norwegian football team and 2 of their male coaches participated in the study. The data analysis revealed two main communication barriers: 1. interpersonal barriers (e.g., false assumptions about the coach/athletes and social discomfort) and 2. knowledge barriers (e.g., unaware/perceptions of insufficient knowledge levels). As the players seemed to be unaware of their insufficient MC knowledge (e.g., failed to see a connection between the MC and their health and performance level), the coaches perceived their knowledge as insufficient and coped mainly by outsourcing MC communication to female staff and apps. Hence, the MC communication was hindered by both the athletes and the coaches (e.g., mutual avoidance). In line with previous research, this study supports that there is a need for developing effective strategies to overcome the interpersonal barriers and knowledge gaps.

Neurodegenerative disease among male elite football (soccer) players in Sweden: a cohort study

Football (soccer) players might be at increased risk of neurodegenerative disease, which has led to questions regarding the safety of the sport and recent measures introduced by football associations to reduce heading of the ball. We aimed to assess the risk of neurodegenerative disease among male football players in the Swedish top division Allsvenskan, compared with matched controls. In this cohort study, we identified all male football players (amateurs and professionals) who had played at least one game in Allsvenskan from Aug 1, 1924 to Dec 31, 2019 and excluded players whose personal identity number could not be retrieved or be identified in the Total Population Register, and those who were not born in Sweden and who had immigrated to the country after age 15 years. Football players were matched with up to ten controls from the general population according to sex, age, and region of residence. We used nationwide registers to compare the risk of neurodegenerative disease (diagnoses recorded in death certificates, during hospital admissions and outpatient visits, or use of prescription drugs for dementia) among football players versus controls. We also assessed each type of neurodegenerative disease (Alzheimer's disease and other dementias, motor neuron disease, and Parkinson's disease) separately, and compared the risk of neurodegenerative disease among outfield players versus goalkeepers. Of 7386 football players who had played at least one game in the top Swedish division between Aug 1, 1924, and Dec 31, 2019, 182 players were excluded for an unretrievable personal identity number, and 417 were excluded due to their number not being identified in the Total Population Register. After a further exclusion of 780 players and 11 627 controls who were born outside of Sweden and who had immigrated to the country after age 15 years, 6007 football players (510 goalkeepers) were included in the study population along with 56 168 matched controls. During follow-up to Dec 31, 2020, 537 (8·9%) of 6007 football players and 3485 (6·2%) of 56 168 controls were diagnosed with neurodegenerative disease. The risk of neurodegenerative disease was higher among football players than controls (hazard ratio [HR] 1·46 [95% CI 1·33-1·60]). Alzheimer's disease and other dementias were more common among football players than controls (HR 1·62 [95% CI 1·47-1·78]), significant group differences were not observed for motor neuron disease (HR 1·27 [0·73-2·22]), and Parkinson's disease was less common among football players (HR 0·68 [0·52-0·89]). The risk of neurodegenerative disease was higher for outfield players than controls (HR 1·50 [95% CI 1·36-1·65]) but not for goalkeepers versus controls (HR 1·07 [0·78-1·47]), and outfield players had a higher risk of neurodegenerative disease than did goalkeepers (HR 1·43 [1·03-1·99]). All-cause mortality was slightly lower among football players than controls (HR 0·95 [95% CI 0·91-0·99]). In this cohort study, male football players who had played in the Swedish top division had a significantly increased risk of neurodegenerative disease compared with population controls. The risk increase was observed for Alzheimer's disease and other dementias but not for other types of neurodegenerative disease, and among outfield players, but not among goalkeepers. Our study expands on the data that can be used to assess and manage risks in the sport. Karolinska Institutet, The Swedish Research Council for Sport Science, Folksam Research Foundation, Hedberg Foundation, Neurofonden, and Åhlen Foundation.

Are Football Players More Prone to Muscle Injury after COVID-19 Infection? The “Italian Injury Study” during the Serie a Championship

Football was the first sport to resume competitions after the coronavirus disease 2019 (COVID-19) lockdown and promptly the hypothesis was raised of a potential relationship between the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection and musculoskeletal injuries in athletes. This study aimed to confirm the association between SARS-CoV-2 infection and muscle strain injury in a large population of elite football players and to investigate if the COVID-19 severity level could affect the risk of injury. A retrospective cohort study involving 15 Italian professional male football teams was performed during the Italian Serie A 2020-2021 season. Injuries and SARS-CoV-2 positivity data were collected by team doctors through an online database. Of the 433 included players, we observed 173 SARS-CoV-2 infections and 332 indirect muscle strains. COVID-19 episodes mostly belonged to severity level I and II. The injury risk significantly increased after a COVID-19 event, by 36% (HR = 1.36, CI95% 1.05; 1.77, p-value = 0.02). The injury burden demonstrated an 86% increase (ratio = 1.86, CI95% 1.21; 2.86, p-value = 0.005) in the COVID-19 severity level II/III versus players without a previous SARS-CoV-2 infection, while level I (asymptomatic) patients showed a similar average burden (ratio = 0.92, CI95% 0.54; 1.58, p-value = 0.77). A significantly higher proportion of muscle-tendon junction injuries (40.6% vs. 27.1%, difference = 13.5%, CI95% 0.002%; 26.9%, p-value = 0.047) was found when comparing level II/III versus Non-COVID-19. This study confirms the correlation between SARS-CoV-2 infection and indirect muscle injuries and highlights how the severity of the infection would represent an additional risk factor.

Association between ACTN3 R577x and the physical performance of Chinese 13 to 15-year-old elite and sub-elite football players at different positions.

The purpose of this study was to investigate the prevalence of ACTN3 polymorphisms in Chinese elite and sub-elite football players aged 13-15years at different positions. Specifically we explored whether ACTN3 genotypes were linked with athletic performance of elite and sub-elite players at different positions. The RR genotype frequency of elite defenders (p = 0.018) and midfielders (p = 0.008) was significantly higher than that of sub-elite XX genotype in elite players. Furthermore, the R allele frequency of elite defenders (p = 0.003) and midfielders (p = 0.008) was significantly higher than that of sub-elite players. In all subjects, RR players performed faster and exhibited more explosive power than RX or XX players. RR, RX and XX elite players' 20m/30m sprint, 5 × 25-m repeated sprint ability (5 × 25m RSA), and standing long jump were stronger than sub-elite players, but there was no significant different in aerobic endurance between elite and sub-elite players at different positions. In conclusion, there were significant differences in ACTN3 genotypes and alleles between elite and sub-elite players at different positions, and the RR genotype was significantly associated with power-related athletic performance in Chinese youth football players.

Relationship between performance, heart rate variability and clinical symptoms in elite football: A case study

Introduction
 Matches and high-intensity training put important load on elite football players, which may result in performance decrease and physiological alterations (Meeusen et al., 2013).
 Positive correlations between heart rate variability (HRV) athletic performance have been reported (Buchheit et al., 2012) but the measurements were not related to match performance. Studies investigating the relationship between HRV and in-match performance data are scarce and none identified typologies of fatigue (Schmitt et al., 2015).
 This is a case study of one elite football player that showed a typical autonomic dysfunction corresponding to a fatigue state with associated clinical symptoms.
 Methods
 A male elite football player playing in French Ligue 1 and continental competitions recorded his beat-to-beat heart rate (Polar H10) during an orthostatic test (5 min supine followed by 5 min standing) systematically 2 days before every match during a series of 8 matches at the rate of 1 match/week. These recordings allowed the assessment of mean heart rate (HR), power spectrum in the low- and high-frequency bands (LF and HF). During each match a GNSS sensor (Vector S7, Catapult) allowed the recording of total distance, acceleration/deceleration above 2m/s. Moreover, the number of passes, passes to the final thirty meters and number of duels and duels won were quantified by video analysis.
 Results
 The player played the entirety of the 8 games mostly as a midfielder and sometimes as a left back. Heart rate in the supine position was inversely correlated to the number of passes and successful passes to final third (R = -0.67, p < 0.05) whilst LF in the standing position was correlated to the duels and duels won (R = 0.75, p < 0.05). In addition, log(HF) was correlated to the number of acceleration during the match whilst log(LF) was correlated with the total distance ran. The player displayed on several occasions a fatigue profile characterized by a parasympathetic hypertonia in the standing position, which ultimately resulted in the player fainting on the pitch.
 Discussion/Conclusion
 HRV during an orthostatic test two days before a match could be useful in identifying fatigue profiles associated with decreased performances and clinical symptoms. Such methods should be used on an entire season and entire squad to better characterize the fatigue profiles in elite football and may help better adapt training sessions.
 References
 Buchheit, M., Simpson, M. B., Al Haddad, H., Bourdon, P. C., & Mendez-Villanueva, A. (2012). Monitoring changes in physical performance with heart rate measures in young soccer players. European Jopurnal of Applied Physiology, 112, 711–723. https://doi.org/10.1007/s00421-011-2014-0
 Meeusen, R., Duclos, M., Foster, C., Fry, A., Gleeson, M., Nieman, D., Raglin, J., Rietjens, G., Steinacker, J., & Urhausen, A. (2013). Prevention, diagnosis, and treatment of the overtraining syndrome: Joint consensus statement of the European College of Sport Science and the American College of Sports Medicine. Medicine & Science in Sports & Exercise, 45(1), 186–205. https://doi.org/10.1249/mss.0b013e318279a10a
 Schmitt, L., Regnard, J., Parmentier, A. L., Mauny, F., Mourot, L., Coulmy, N., & Millet, G. P. (2015). Typology of “Fatigue” by heart rate variability analysis in elite nordic-skiers. International Journal of Sports Medicine, 36(12), 999–1007. https://doi.org/10.1055/s-0035-1548885

Is quality of movement a factor that affects reaching the professional level in elite young football players?

Objective: The aim of the study was to examine whether the proportion of young elite football players with high functional movement screening (FMS) scores and reaching professionalism differs from the proportion of young elite football players with low FMS scores and non-professionals. Materials and Methods: Fifty-seven players were included in the study. The health files of the participants were retrospectively scanned. Physical information and FMS scores were recorded in the data form. The level of football career of the participants as of March 2022 was assessed on the website of the Turkish Football Federation. FMS scores were compared by dividing the participants into two groups as those with- and without professional football license. Results: The proportion of participants with a score above the FMS cut-off score and reaching the professional level was higher than the rate of non-professional participants with a score above the FMS cut-off score (p˂0.05). Conclusion: The quality of movement in young elite football players may be a determinant for being a professional football player. For this reason, starting from an early age, measuring the quality of movement regularly and trying to improve it may be important in realizing the career goals of elite young football players.

Relationship between Repeated Sprint Ability, Countermovement Jump and Thermography in Elite Football Players.

Football is a very demanding sport which requires players to exert maximum effort, producing fatigue and eventually injuries. Thermography can be used to detect fatigue and prevent its consequences through thermal asymmetries in the bilateral body areas; however, its adequacy for elite footballers has not been widely studied. Therefore, the objective of the present investigation was to determine the suitability of thermography to detect fatigue in male football players. For this reason, twenty participants were gathered into a pair of subgroups (low [<0.2 °C] vs. high thermal asymmetry [≥0.2 °C]) based on a thermography session of the lower limbs (thighs, calves, and hamstrings). After the thermography session, players performed CMJs before and after an RSA test (6 × 30 m/20″). A mixed two-way analysis of variance and Bonferroni post hoc pairwise comparisons were undertaken to analyse the results. No significant differences (p > 0.05) were found in any of the RSA test variables between low and high thermal asymmetry groups for thighs and calves. On the other hand, the low thermal asymmetry hamstring group reported a smaller percentage difference in sprints for the first sprint (%Diff) and a larger percentage difference in sprints two and three with respect to the best sprint (%Best). For CMJs, the low thermal asymmetry hamstring group reported significantly higher values post-RSA test, indicating better performance. Accordingly, thermography can provide information about performance in CMJ and RSA tests through hamstring asymmetries over 0.2 °C. Meanwhile, larger asymmetries than 0.2 °C in calves and thighs do not seem to be related to performance in these tests; therefore, coaches should consider if it is optimal to align players with high hamstring asymmetries.

Accuracy of flight time and countermovement-jump height estimated from videos at different frame rates with MyJump.

Recent improvements in smartphone video technology may provide sufficient accuracy for estimation of jump height via flight time determined from video recordings of vertical-jump tests. The aim of this study is to evaluate the accuracy of jump height estimated from videos at different frame rates. High-definition videos of 10 young adults (6 males, 4 females) performing 5 countermovement jumps were recorded at a frame rate of 1000 Hz and transcoded to frame rates of 120, 240, and 480 Hz. Flight time in the videos was assessed independently by three observers at each of the four frame rates with MyJump. Flight time and jump height were analyzed with mixed models for estimation of means and of standard deviations representing technical error of measurement (free of within-subject jump-to-jump variability) at each frame rate. The four frame rates and three observers produced practically identical estimates of mean jump height. The technical errors at 120, 240, 480 and 1000 Hz were respectively 3.4, 1.8, 1.2 and 0.8 ms for flight time, and 1.4%, 0.7%, 0.5% and 0.3% for jump height. Assessed relative to either differences in jump height between elite football players (standard deviation of ~12%) or the smallest expected test-retest variability (typical error of ~3%), the technical error was substantial at 120 Hz but negligible at 240 Hz or higher. In conclusion, use of frame rates above 240 Hz to estimate jump height with MyJump will not improve accuracy substantially.

Can prognostic factors for indirect muscle injuries in elite football (soccer) players be identified using data from preseason screening? An exploratory analysis using routinely collected periodic health examination records

BackgroundIn elite football, periodic health examination (PHE) may be useful for injury risk prediction.ObjectiveTo explore whether PHE-derived variables are prognostic factors for indirect muscle injuries (IMIs) in elite players.DesignRetrospective cohort...

An investigation on aggression levels among elite women football players

Background: To compete at the greatest level on the global stage in a sporting event, psychological balance is as crucial as physical condition. Many uncontrolled actions among athletes, such as physical aggressiveness, hostility, hostile and verbal aggression, are common these days. Objectives: Both men and women bear equal responsibility. As a result, the purpose of this study is to analyse the amount of violence in Manipur&#39;s elite women football players. For this study 17 national level women footballers (age 23±1.52 years, height 161±3.2 cm and body weight 54±4.3 kg) has been participated. Material and Methods: The Buss-Perry Aggression Questionnaire (BPAQ) was used to collect data. The study&#39;s findings revealed that all of the participants were aggressive. 53% of the individuals were extremely aggressive. 6% were aggressive, whereas 41% were less aggressive. Conclusion: It was discovered that hostile and anger were highly connected with the players&#39; behaviour among the aggressiveness factors (physical aggression, anger, hostile, and verbal aggression). As a result of the findings, it is possible to conclude that psychological training is critical for controlling aggression on the playing field and maintaining game ethics.

Prevalence of upper extremity pain and disability in elite football, ice hockey and floorball players

In athletes, injuries and medical conditions affecting the upper extremities are quite common. However, there has been limited research on the occurrence of joint pain in the peripheral upper extremities among elite athletes. Thus, this study aimed to determine how prevalent upper limb pain and disability are among team sports players, particularly in football, ice hockey and floorball. We also aimed to compare the severity of pain and disability among these sports and assess the risk of developing upper limb pain in athletes. This cross-sectional study was conducted between June 2021 and September 2022, involving 388 male elite athletes from national-level sports clubs. The prevalence of shoulder pain and disability was determined using the Shoulder Pain and Disability Index (SPI). Assessment of elbow pain and disability was conducted using the Oxford Elbow Score (OES), while wrist pain and disability were evaluated through the Patient-Rated Wrist Evaluation (PRWE). Significant differences in total SPI, OES and PRWE scores were observed among all groups. Ice hockey players experienced the highest levels of shoulder and wrist pain. Compared to football and floorball players, ice-hockey players had a 2.13 times higher risk of shoulder pain, with a pain incidence of 40.8%. Ice hockey also had a 1.71 times higher risk of wrist pain than football, with a pain prevalence of 26.3%. Notably, floorball players exhibited the most pronounced elbow pain, with a 13.18-fold higher risk than football and ice-hockey players and a pain prevalence of 67.2%. The study findings suggest that ice hockey players experience the highest pain levels in their right limbs, whereas football players have the lowest pain levels, underscoring the importance of dedicating more attention to developing innovative, effective and advanced preventive programs for athletes.

Contextualised high-intensity running profiles of elite football players with reference to general and specialised tactical roles

The present study aimed to contextualise physical metrics with tactical actions according to general and specialised tactical roles. A total of 244 English Premier League players were analysed by coding player's physical-tactical actions via the fusion of tracking data and video. Data were analysed across 5 general (Central Defensive Players = CDP, Wide Defensive Players = WDP, Central Midfield Players = CMP, Wide Offensive Players = WOP, Central Offensive Players = COP) and 11 specialised positions (Centre Backs = CB, Full-Backs = FB, Wing-Backs = WB, Box-to-Box Midfielders = B2BM, Central Defensive Midfielders = CDM, Central Attacking Midfielders = CAM, Wide Midfielders = WM, Wide Forwards = WF, Centre Forwards = CF). COP covered more distance at high-intensity (> 19.8 km · h-1) when performing actions such as 'Break into Box', Run in Behind/Penetrate', and 'Close Down/Press' than other positions (ES: 0.6-5.2, P < 0.01). WOP covered more high-intensity 'Run with Ball' distance (ES: 0.7-1.7, P < 0.01) whereas WDP performed more 'Over/Underlap' distance than other positions (ES: 0.9-1.4, P < 0.01). CDP and WDP covered more high-intensity 'Covering' distances than other positions (ES: 0.4-2.4, P < 0.01). Nonetheless, data demonstrated that implementing specialised positional analysis relative to a generalised approach is more sensitive in measuring physical-tactical performances of players with the latter over or underestimating the match demands of the players compared to the former. A contextualised analysis may assist coaches and practitioners when designing position or even player-specific training drills since the data provides unique physical-tactical trends across specialised roles.

Effects of conditioning activities and time of day on male elite football players

Effects of conditioning activities and time of day on male elite football players

Physical and anthropometric profile of Tunisian elite football players according to their playing position: A longitudinal study

Background: In elite youth soccer, the extent to which anthropometric and physical fitness parameters vary according to playing positions remains unclear. Identifying and quantifying these differences is crucial for informing targeted training interventions. Objectives: We aimed to investigate the evolution anthropometric and physical profiles in Tunisian elite youth soccer players during one season, and to analyze differences between players according to their playing position. Methods: Sixty-two subjects (15.3±0.2 years, 69.4±6.4 kg, 176.9±4.8 cm) playing for the top four professional football clubs in Tunisia took part in the study. They were divided into five groups according to their playing position: goalkeepers (n=10), fullbacks (n=14), central defenders (n=11), midfielders (n=15) and forwards (n=12). Various anthropometric measurements, fitness tests assessing aerobic and anaerobic performance were performed at two times (T): T1 (3 weeks after the beginning of the preparation period), and T2 (end of the competitive period). Results: Football players across all positions exhibited significant anthropometric growth, particularly in height, with increases from small to moderate (p &lt; 0.001; effect size (ES) = 0.30 to 0.57). Weight changes were non-significant (p = 0.01 to 0.14; ES = 0.01 to 0.14), while fat mass reductions across positions were slightly more pronounced (p = 0.05 to 0.25; ES = 0.09 to 0.25). Performance metrics revealed substantial improvements, particularly in the 5-Jump Test, where forwards excelled (p &lt; 0.001; ES = 1.07), and in sprinting events, where consistent progress was noted across all positions (p &lt; 0.001; ES = 0.16 to 0.33). The Yo-Yo Intermittent Recovery Test exhibited significant enhancements, again with forwards achieving the greatest gains (p &lt; 0.001; ES = 3.01). Conclusion: The study emphasizes the need for position-specific training in youth football, highlighting how physical and anthropometric characteristics vary by playing position. The results suggest that tailored training can enhance performance and development in young players, reinforcing the importance of customized approaches for different positions in elite youth soccer. This approach not only improves player performance but also aids in effective talent identification and injury prevention of youth soccer players.

Dietary Intake, Body Composition and Performance of Professional Football Athletes in Slovenia

This is the first study to examine the nutritional status of professional Slovenian football players. This study aimed to analyze the dietary intake of elite football players during their preparation phase of the season and to investigate whether there is a relationship between energy and macronutrient intake with body composition and physical performance. Twenty-three footballers completed a three-day dietary and physical activity diary and underwent body composition measurements via bioelectrical impedance vector analysis (BIVA). Fifteen participants also took part in the Cooper treadmill test to assess their physical performance in correlation with their nutritional intake. Football players had an energy intake that was significantly too low for their needs, reflecting low energy availability. The average carbohydrate (CHO) intake was below the Union of European Football Associations (UEFA) recommendations, i.e., <4 g CHO/kg body weight (BW). Additionally, players had adequate intakes of protein and fat, and inadequate intakes of saturated fat, fiber, calcium and vitamin D. There was a positive correlation between protein intake and lean body mass. Additionally, a negative correlation was observed between body fat mass and carbohydrate intake as well as between performance with the percentage of energy intake from fat. Results of this study highlight what aspects of nutrition might be improved upon in professional football players to maximize performance, longevity and body composition of athletes, as well as the necessity of a nutritionist role in this process.

Alcohol related disorders among elite male football players in Sweden: nationwide cohort study

ObjectivesTo assess whether male elite football players are at increased risk of alcohol related disorders compared with men from the general population, and whether such an increased risk would vary...

Performance Adaptations to Intensified Training in Top-Level Football.

Because physical demands are surging in football (soccer, USA), clubs are more and more seeking players who have a high capacity to perform repeated intense exercise. High-intensity interval training (HIIT), comprising exercise performed at intensities near or exceeding the capacity of aerobic energy systems, effectively enhances the physical conditioning of players. But given that HIIT imposes high loads, it increases the risk of overload-associated match performance decline and injury. This makes some coaches inclined to conduct HIIT in the weeks leading up to the season and during the season. Therefore, the challenge is how to optimize and dose HIIT during these phases, as they can be decisive. Studies have highlighted the utility of conducting periods of intensified training to overcome the risk of overload while at the same time enhancing performance. During intensified training periods of typically a few weeks, intensity is increased by enlarging the amount of HIIT, for example, aerobic high-intensity training or speed endurance training, while volume at low-to-moderate intensity is significantly reduced. The outcome depends on training composition and prescription-most notably, intensity and duration of bouts and recovery. When work intervals are prescribed for a few minutes at intensities > 90% heart rate max (i.e., aerobic high-intensity training), then beneficial adaptations pertaining to aerobic power and capacity are apparent. But when work intervals are conducted at much higher intensities, as all-out efforts or sprinting of typically 10- to 40-s duration with longer recovery periods (i.e., speed endurance training), beneficial adaptations pertaining to anaerobic energy systems, ion handling, and fatigue resilience are commonly observed. In this review, we discuss the utility of conducting intensified training periods to enhance performance in elite football players during the late preparation phase and competitive season.

Effect of playing position and microcycle days on the acceleration speed profile of elite football players

The aim of this study was to analyse the differences in the A–S profile of elite football players induced by playing position and the microcycle day. Players belonged to a second division club in the Spanish La Liga competition. They were classified into five playing positions: central defenders (CD), full backs (FB), midfielders (MF), wide midfielders (WMF) and forwards (FW). Microcycle days were categorised according to the days until matchday (MD, MD-1, MD-2, MD-3, MD-4 and MD-5). Data was collected along six microcycles, including one match per microcycle. The variables analysed were: maximal theoretical acceleration (A0), maximal theoretical speed (S0), maximal acceleration (ACCmax), maximal speed (Smax) and A–S slope (ASslope). Significant differences were found within positions and microcycle day for all variables (p < 0.05). Match day (MD) showed greater values than the training sessions in A0, ACCmax and Smax (p < 0.05). The highest values for variables associated with acceleration capabilities were found in CD on MD, whereas speed variables were higher in WMF. MD-2 showed the lowest values in all variables except for ASslope. Maximal acceleration and sprint abilities are therefore affected by playing position. Wide positions showed the highest speed capacity, and CD presented a likely acceleration profile. Higher values for all variables concerning the microcycle day, were achieved on MD, and were not reproduced during training with the consequent injury risk and performance decrease it takes.