Latest research in football - week 42 - 2022

As previous literature updates, I have performed a PubCrawler search looking for football articles in NCBI Medline (PubMed) and GenBank databases. 


Following studies were retrieved for this week:

#1 Decline in Running Performance in Highest-Level Soccer: Analysis of the UEFA Champions League Matches

Reference: Biology (Basel). 2022 Oct 1;11(10):1441. doi: 10.3390/biology11101441.

Authors: Toni Modric, Sime Versic, Dan Iulian Alexe, Barbara Gilic, Ilie Mihai, Patrik Drid, Nikola Radulovic, Jose M Saavedra, Rafael Burgueño Menjibar

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Summary: It is widely recognized that there is a decline in match running performance (MRP) towards the end of matches. To clarify whether it is primarily a consequence of fatigue, pacing or situational influences, this study aimed to examine MRP across 15-min match periods for players on different playing positions. Players' MRP (n = 244) were examined from the UEFA Champions League matches (n = 20) using a semiautomatic optical tracking system. Linear mixed models for repeated measures were adjusted to analyze MRP over the six 15-min match periods while controlling the influence of situational factors. No effects of match outcome, match location, team, and opponent quality on total distance (TD) and high-intensity running (HIR) for players in all playing positions were found (F = 0.03-2.75; all p > 0.05). Significant differences in TD (F = 17.57-53.01; η2 = 0.39-0.52, all large effect sizes) and HIR (F = 3.67-7.64; η2 = 0.05-0.19, small to medium effect sizes) among six 15-minute match periods were found for players in all playing positions. In addition, players in all playing positions covered less TD (d = 1.41-2.15, large to very large effect sizes) and HIR (d = 0.16-0.6, trivial to medium effect sizes) in the last compared to the first 15-min match period. No differences in TD and HIR between the last two match periods in the second half were observed. This study confirmed that soccer players reduce MRP towards the end of matches, and suggest that the decline of MPR in highest-level soccer may be a consequence of pacing strategies.



#2 Effects of perceptual-cognitive tasks on inter-joint coordination of soccer players and ordinary college students

Reference: Front Psychol. 2022 Oct 5;13:892118. doi: 10.3389/fpsyg.2022.892118. eCollection 2022.

Authors: Yuanyuan Ren, Cenyi Wang, Aming Lu

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Summary: Perceptual-cognitive tasks play a pivotal role in performing voluntary movements, which is crucial for good performances among soccer players. This study explored the effect of perceptual-cognitive tasks on the inter-joint coordination of soccer players and college students during landing. The classic multiple objective tracking (MOT) task was used to simulate the perceptual-cognitive task under a sports environment. Fifteen soccer players (age: 20.1 ± 1.5 year, height: 181.4 ± 7.4 cm, weight: 75.4 ± 10.7 kg) and twenty ordinary college students (age: 20.0 ± 2.3 years, height: 177.9 ± 4.9 cm, weight: 71.6 ± 9.9 kg) were enrolled to the study. Participants in the two groups were subjected to a single task (landing task) and dual-task (MOT task and landing task). Coordination and variability indicators were recorded using a Vicon infrared motion capture system and a force measuring platform. The results showed that the mean absolute relative phase of hip and knee joint (MARPhip-knee), deviation phase of hip and knee joint (DPhip-knee), and deviation phase of knee and ankle joint (DPknee-ankle) of the two groups under the dual-task were significantly different compared with the parameters when participants were subjected to the single task. The dual-task had higher effect size on DPhip-Knee and MARPhip-knee, indicating that dual-task had a greater impact on coordination of the hip and knee joints. DPhip-knee and DPknee-ankle of ordinary students were more extensive relative to those of the soccer players, and hip joint stiffness (K hip) for ordinary students was lower than that of the soccer players under the different tasks. These findings implied that the perceptual-cognitive task markedly affected the inter-joint coordination of soccer players and college students, mainly by impairing the hip and knee coordination. Although there is less variability in lower extremity coordination patterns of soccer players compared to college students, the MOT task still affects their coordination ability.



#3 Meniscal lesion or patellar tendinopathy? A case report of an adolescent soccer player with knee pain

Reference: J Can Chiropr Assoc. 2022 Aug;66(2):157-171.

Author: Antonio Petrolo

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Summary: Injuries to the meniscus are particularly prevalent in soccer players, with an incidence of 0.448 injuries per 1000 hours of playing. However, in the adolescent soccer player population, it has been reported that up to 63% of asymptomatic knees may demonstrate horizontal or oblique tears on MRI. These results may negatively influence clinical decision-making and plan of management for adolescent soccer players with knee problems. A case of a 15-year-old soccer player is presented after having been diagnosed by his family physician with a left lateral meniscus tear as per MRI, following a 10-week period of anterior knee pain. He presented to a chiropractor for a second opinion before consulting with the orthopedic surgeon. Recommendations for progressive rehabilitation owing to the lack of clinical evidence for meniscal abnormality were made. A primary diagnosis of left patellar tendinopathy was determined and after a 6-week comprehensive rehabilitation program, the patient made a complete recovery. A thorough history, physical examination, and understanding of the patient's injury mechanism are suggested before confirming/refuting suspicions of meniscal abnormalities via MRI. This will help to inform better clinical decision-making as well as decrease the occurrence of unnecessary imaging.



#4 Does a 40-week Football and Zumba exercise intervention influence self-reported job satisfaction, work role functioning and sick leave among female hospital employees? A cluster-randomised controlled trial

Reference: Eur J Sport Sci. 2022 Oct 28;1-21. doi: 10.1080/17461391.2022.2139634. Online ahead of print.

Authors: Svein Barene, Peter Krustrup, Andreas Holtermann

Summary: This 40-week cluster-randomized controlled trial (RCT) examines the effects of football and Zumba on self-perceived job satisfaction, work role functioning and sick leave among Norwegian female hospital employees. Hundred-and-seven employees, mainly consisting of nurses (80%), were allocated into three groups; Football (FG), Zumba (ZG) and Control (CG). The exercise groups were offered 2-3 and 1-2 one-hour weekly sessions during the first 12 and last 28 weeks, respectively, with an actual weekly exercise frequency of 2.4 ± 0.5 and 0.9 ± 0.2 in FG and 2.3 ± 0.3 and 0.8 ± 0.2 in ZG. Outcome variables were measured at baseline, 12 and 40 weeks. In comparison to CG (4.8 days 95% CI 3.2 to 6.4), ZG (1.9 days, 95% CI 0.4 to 3.5) had a significant lower overall mean days of sickness absence during last sick leave period (-2.9 days, 95% CI -5.1 to -0.7, p = 0.011) which corresponded to a moderate effect size (d = 0.60). Between baseline (88.5%, 95% CI 84.3 to 92.6) and 12 weeks (93.8%, 95% CI 89.4 to 98.2), ZG showed significant within-group improvement in total score of the Work Role Functioning Questionnaire (WRFQ) (5.3%, 95% CI 0.6 to 10.1, p = 0.029), corresponding to a moderate effect size (d = 0.40). This study indicates that two to three 1-hour weekly Zumba sessions can have a preventive effect on sick leave in female hospital employees.Highlights Participants in Zumba exercise organized by the workplace showed a significant lower number of sick leave days compared with the controlsDespite a correspondingly significant reduction in exercise adherence in both groups in the last 28 weeks, only FG showed tendencies for group improvement in job satisfaction and total WRFQ in this periodWorkplace promotion of exercise and physical activity can thus be beneficial for both the workers and the organization.



#5 Relationships between Internal Training Intensity and Well-Being Changes in Youth Football Players

Reference: Healthcare (Basel). 2022 Sep 21;10(10):1814. doi: 10.3390/healthcare10101814.

Authors: Rui Miguel Silva, Filipe Manuel Clemente, Francisco Tomás González-Fernández, Hadi Nobari, Rafael Oliveira, Ana Filipa Silva, José María Cancela-Carral

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Summary: The aim of this study was two-fold: (i) to analyze the variations of training intensity and well-being measures of youth football player over a 38 week period; and (ii) to test the relationships between training intensity and well-being variations throughout a youth football season. This study followed a longitudinal design, lasting 38 weeks. Twenty-five players (age: 15.0 ± 0.4 years) participated in this study. Participants were monitored daily to quantify the training intensity (TI) using the session-rate of perceived exertion (s-RPE) and its related indices: training monotony (TM), weekly training intensity (wTI), mean training intensity (mTI), and 5-day average (5d-AVG). A four-item questionnaire was collected daily to quantify the well-being status of each player. Fatigue, stress, delayed onset muscle soreness (DOMS), sleep quality, and the Hooper Index (HI) measures were analyzed. Kruskal-Wallis H test revealed significant differences for TM, mTI, wTI and 5d-AVG (H = 359.53, p = 0.001, η2 = 0.35; H = 414.97, p = 0.001, η2 = 0.41, H = 258.42, p = 0.001, η2 = 0.24 and H = 282.18, p = 0.001, η2 = 0.26). A positive large correlation was found between TM and sleep quality (r = 0.65, p = 0.05) and a negative large correlation between mTI and sleep quality (r = -0.69, p = 0.04). In conclusion, both TI and well-being measures present significant between-week differences at different periods of the season. Also, the variations of sleep quality seem to depend on TM and mTI variations across a youth football season.



#6 Sport-Specific Rehabilitation, but Not PRP Injections, Might Reduce the Re-Injury Rate of Muscle Injuries in Professional Soccer Players: A Retrospective Cohort Study

Reference: J Funct Morphol Kinesiol. 2022 Sep 21;7(4):72. doi: 10.3390/jfmk7040072.

Authors: Eduard Bezuglov, Vladimir Khaitin, Maria Shoshorina, Mikhail Butovskiy, Nikita Karlitskiy, Evgeny Mashkovskiy, Evgenii Goncharov, Bekzhan Pirmakhanov, Ryland Morgans, Artemii Lazarev

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Summary: Platelet-rich plasma (PRP) injections are extremely popular in the management of sports injuries in elite athletes. However, data on the use of various administration protocols of PRP are contradictory. The efficacy of platelet-rich plasma in the treatment of muscle injuries in professional soccer players has to be contextualized within the sport-specific rehabilitation program. Despite the questionable role of PRP, a well-structured rehabilitation program is still regarded as the gold standard. We examined the efficacy of various PRP protocols in the management of muscle injuries in professional soccer players in respect to treatment duration and injury recurrence. A retrospective cohort study. Muscle injuries in professional soccer players (n = 79, height 182.1 ± 5.9 cm, weight 76.8 ± 5.8 kg, BMI 23.1 ± 1.4 kg/m2) from three elite soccer clubs from the Russian Premier League were recorded during the 2018-2019 season. The injuries were graded based on MRI, using the British Athletic Muscle Injury Classification. Treatment protocols included the POLICE regimen, short courses of NSAID administration, and the specific rehabilitation program. The sample group of players were administered PRP injections. The average treatment duration with PRP injection was significantly longer than conventional treatment without PRP, 21.5 ± 15.7 days and 15.3 ± 11.1 days, respectively (p = 0.003). Soccer-specific rehabilitation and obtaining MRI/US before the treatment was associated with significantly reduced injury recurrence rate (p < 0.001). There was no significant difference between the PRP injection protocol applied to any muscle and the treatment duration in respect of grade 2A-2B muscle injuries. The total duration of treatment of type 2A-2B injuries was 15 days among all players. In the group receiving local injections of PRP, the total duration of treatment was 18 days; in the group without PRP injections, the treatment duration was 14 days. In our study, PRP treatment was associated with longer treatment duration, regardless of which muscle was injured. This may reflect the tendency to use PRP in higher-degree injuries. Soccer-specific rehabilitation significantly reduced the injury recurrence rate when compared to the administration of PRP injections. MRI/US imaging before returning to play was also associated with a lower injury recurrence rate. There was no significant difference between the PRP injection protocol applied to any muscle and the treatment duration in treatment of type 2A-2B muscle injuries.



#7 A Multidisciplinary Investigation into the Talent Development Processes at an English Football Academy: A Machine Learning Approach

Reference: Sports (Basel). 2022 Oct 19;10(10):159. doi: 10.3390/sports10100159.

Authors: Adam L Kelly, Craig A Williams, Rob Cook, Sergio Lorenzo Jiménez Sáiz, Mark R Wilson

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Summary: The talent development processes in youth football are both complex and multidimensional. The purpose of this two-fold study was to apply a multidisciplinary, machine learning approach to examine: (a) the developmental characteristics of under-9 to under-16 academy players (n = 98; Study 1), and (b) the characteristics of selected and deselected under-18 academy players (n = 18; Study 2). A combined total of 53 factors cumulated from eight data collection methods across two seasons were analysed. A cross-validated Lasso regression was implemented, using the glmnet package in R, to analyse the factors that contributed to: (a) player review ratings (Study 1), and (b) achieving a professional contract (Study 2). Results showed non-zero coefficients for improvement in subjective performance in 15 out of the 53 analysed features, with key findings revealing advanced percentage of predicted adult height (0.196), greater lob pass (0.160) and average dribble completion percentage (0.124), more total match-play hours (0.145), and an older relative age (BQ1 vs. BQ2: -0.133; BQ1 vs. BQ4: -0.060) were the most important features that contributed towards player review ratings. Moreover, PCDEQ Factor 3 and an ability to organise and engage in quality practice (PCDEQ Factor 4) were important contributing factors towards achieving a professional contract. Overall, it appears the key factors associated with positive developmental outcomes are not always technical and tactical in nature, where coaches often have their expertise. Indeed, the relative importance of these factors is likely to change over time, and with age, although psychological attributes appear to be key to reaching potential across the academy journey. The methodological techniques used here also serve as an impetus for researchers to adopt a machine learning approach when analysing multidimensional databases.



#8 Assessment of Vaccination Status in Professional Football Players in Low Categories in Greece

Reference: J Funct Morphol Kinesiol. 2022 Sep 26;7(4):73. doi: 10.3390/jfmk7040073.

Authors: Dimitrios Papagiannis, Georgios Marinos, Ioannis Anyfantis, Georgios Rachiotis

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Summary: There are limited data on the vaccination practices of footballers in low professional categories in Greece and Europe. The aim of this study was to investigate the vaccination practices followed by the medical staff of the low professional football categories in Central Greece. A questionnaire was developed and included questions on the vaccination practices of football players. The participants were chief medical officers of the fifteen low-category football teams in Central Greece. Overall, 10 out of 15 chief medical officers participated (response rate: 67%). All participants recommended only the tetanus monovalent vaccine in cases with deep trauma of athletes. Influenza, pneumococcal vaccine, and Hepatitis A and B vaccines were not recommended by the medical officers. This was also the case for measles, mumps, rubella (MMR) vaccine and meningococcal vaccine with strains A, C, Y, W. Participants reported the lack of specific guidelines for vaccination in professional footballers. The recent study showed poor vaccination practices in low categories of professional football teams in Central Greece. The qualitative view of the respondents revealed the importance of the absence of guidelines on vaccination of football players.



#9 Chinese physical fitness standard for campus football players: A pilot study of 765 children aged 9 to 11

Reference: Front Physiol. 2022 Oct 5;13:1023910. doi: 10.3389/fphys.2022.1023910. eCollection 2022.

Authors: Hong Jia, Bin Wan, Te Bu, Yang Luo, Weiping Ma, Sen Huang, Liang Gang, Wei Deng, Zeyong Liu

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Summary: In 2022, 55 million Chinese children participate in campus football; however, there is no physical fitness standard, making it a priority task to enhance the current national program. This study aimed to explore a pilot method for the development of a reliable physical fitness standard. This study examined 765 male football players aged 9 to 11 in 2020 and 2022. The anthropometric and physical fitness assessments were conducted in accordance with the Chinese Football Association's field manuel. Physical fitness tests include sit and reach test, t test, 30 m run test, and vertical jump test. Physical fitness standard was modeled using the generalized additive models for location, scale, and shape (GAMLSS). Data were fitted with appropriate GAMLSS distributions and smoothing term. P-splines were applied to smooth the model's parameters using the default local maximum likelihood method and link functions. Following diagnostics of fitted models, age-specific centile estimations were computed for physical fitness tests. In addition, players in each age group were categorized according to their body mass index as normal weight or overweight/obese. Welch's t-test was utilized to compare the group differences in physical fitness testing. The significance level was chosen at p < 0.05. Sit and reach test, t test, 30 m run test, and vertical jump test data were fitted with original Sinh-Arcsinh, Box-Cox power exponential, Box-Cox power exponential, and Box-Cox Cole and Green, respectively. Physical fitness standard for each age group is presented as tabulated centiles (1p, 3p, 5p, 15p, 25p, 50p, 75p, 85p, 95p, 97p, 99p). Overweight/obese campus football players did significantly worse (p < 0.05) on the t test, 30 m run test, and vertical jump test than their normal-weight peers of the same age. This study developed the first physical fitness standard for 9 to 11-year-old campus football players in China. We made three recommendations to Chinese policymakers on sample size, data management, and field procedure for the creation of a national physical fitness standard.



#10 Non-steroidal anti-inflammatory drugs in football - a "Keeping SCORE" approach to judicious use

Reference: Sci Med Footb. 2022 Oct 28;1-5. doi: 10.1080/24733938.2022.2140189. Online ahead of print.

Authors: Craig Rosenbloom, Katrine Okholm Kryger, Sean Carmody, Daniel Broman

Summary: Non-steroidal anti-inflammatory drug (NSAID) use in elite sport is high, with football being no exception. Increased awareness of significant adverse drug reactions from published research and retired players commentary in the media have made the topic mainstream. Despite this increased awareness, usage rates show no sign of significantly reducing. Footballers, like all elite athletes are focused on maximising their performance and potential - even at the expense of their long-term health. An educational intervention prior to the 2010 FIFA Men's World Cup aimed at reducing rates was ineffective, suggesting that education alone is not the answer. Our author group propose a 'safer use' rather than 'no use' of NSAIDs in football. A 'Keeping SCORE' approach is suggested, designed as a prescribing aid. The approach guides medical staff towards focusing on Safety checks, Clinical indication/judgement, Open dialogue, Recording, and Evaluation.



#11 'If I am playing football, I forget that I have this virus': the challenges and coping strategies of adolescents with perinatally acquired HIV in KwaZulu-Natal, South Africa

Reference: BMC Infect Dis. 2022 Oct 21;22(1):796. doi: 10.1186/s12879-022-07780-x.

Authors: Marian Loveday, Jennifer Furin, Sindisiwe Hlangu, Thabile Mthethwa, Tasneem Naidoo

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Summary: Adolescents who have acquired HIV perinatally (ALHIV) face unique challenges in taking lifelong antiretroviral therapy (ART), but little is known about what factors affect their adherence over the course of their lifelong treatment journey. We conducted a qualitative study with ALHIV who had periods of poor adherence to ART in KwaZulu-Natal, South Africa using Participant-generated Visual Methodologies (PVM). Participants used photography to represent their perspectives and experiences. 14 individuals participated in the research process. We developed a framework and identified four social domains which combined with the adolescent's own experiences and sense of self to either support or undermine adherence. Periods of non-adherence were reported by all participants. Participants described the importance of supportive relationships and households as well as the benefits of ART as supporting adherence. The fear of inadvertent disclosure of their HIV status and the side-effects of ART were barriers to adherence. Possible interventions to support adolescents in their treatment journey are identified. Current models of adherence support fail to address the challenges to lifelong therapy ALHIV face. Ongoing education and honest communication with health care providers, interventions that build resilience together with peer support, have the potential to improve adherence in ALHIV.



#12 Effect of the Length of the Microcycle on the Daily External Load, Fatigue, Sleep Quality, Stress, and Muscle Soreness of Professional Soccer Players: A Full-Season Study

Reference: Sports Health. 2022 Oct 30;19417381221131531. doi: 10.1177/19417381221131531.

Authors: José M Oliva Lozano, José M Muyor, Andrés Pérez-Guerra, David Gómez, Jorge Garcia-Unanue, Javier Sanchez-Sanchez, José Luis Felipe

Summary: The aim of this study was to analyze the effect of the length of the microcycle (ie, training period from the day after the match to the following match) on the daily external load and perceived wellness of professional soccer players (Spanish LaLiga Smartbank). We hypothesized that the length of the microcycle has a significant effect on the daily external load and perceived wellness. Data were collected daily during a full season using perceived wellness questionnaires and electronic performance and tracking systems. The length of the microcycle had a significant effect on volume- and intensity-related external load variables. There were differences between short, regular, and long microcycles depending on the day of the microcycle. These differences were observed in all external load variables. However, no significant differences between short, regular, or long microcycles were found on match day for any external load variable, except for high-intensity decelerations. Regarding the perceived wellness, the length of the microcycle had no effect on these variables, and there were no significant interactions between the length and the day of the microcycle. The length of the microcycle had a significant effect on volume- and intensity-related external load variables, but no significant effect on perceived wellness was observed. These data may help strength and conditioning coaches understand that workload periodization should take this contextual variable into account, especially for external training load. In addition, this study may serve as a guide for practitioners to know the physical requirements of professional soccer players in Spanish LaLiga Smartbank, because the weekly external load profile and perceived wellness have been reported for different lengths of the microcycles. Thus, these data may be used for player load management.



#13 Decrease in aerial challenges after revision of goal kick rules in Japan Professional Soccer League: explorative study of the possibility of a risk reduction for head injury, concussion, and brain damage by a rule revision

Reference: Sci Med Footb. 2022 Nov 3;1-6. doi: 10.1080/24733938.2022.2142274. Online ahead of print.

Authors: Kenichi Shibukawa, Yoshihiro Hoshikawa

Summary: In 2019, FIFA revised the goal kick (GLK) rule such that a GLK could be performed even if the kicker had teammates in the penalty area. This study aimed to examine whether the rule revision reduced the frequency of aerial challenge (AC) and long GLKs (LGLKs), which are risk factors for head injury and concussion in soccer. We analyzed all official league matches (306 matches/season) of the Japan Professional Soccer League 1st Division before (2018 season) and after the rule revision (2020 season). The analysis categorized GLKs into short GLKs (SGLKs) and LGLKs, depending on the GLK distance, and included the frequency and causes of AC, in each match following a GLK, which were compared between the 2018 and 2020 seasons. The average number of LGLKs per match in the 2020 season (8.85) decreased compared to that in the 2018 season (14.20). Additionally, for ACs following a GLK, the frequency of ACs decreased from 6.08 to 3.92 per match. Meanwhile, the frequency of LGLKs tended to increase toward the end of the first and second halves in matches. The results of this study revealed that the 2019 GLK rule revision reduced the number of LGLKs and ACs.



#14 No Association Between Processing Speed and Risk of Sport-Related Concussion in Youth Soccer

Reference: Clin J Sport Med. 2022 Nov 1;32(6):e587-e590. doi: 10.1097/JSM.0000000000001064.

Authors: Ruby Lopez-Flores, Jessie Oldham, David Howell, Justin Rush, Alex Taylor, Paul Berkner, Rebekah Mannix, William P Meehan 3rd

Summary: The aim was to determine whether slow processing speed is associated with risk of sport-related concussion. We conducted a retrospective cohort study using computerized neurocognitive assessments (Immediate Post-concussion Assessment and Cognitive Testing [ImPACT]) from the Massachusetts Concussion Management Coalition. Slow processing speed was defined as 2 SD below the sample mean (n = 131) and fast processing speed as 2 SD above the sample mean (n = 259). We used a binary logistic regression model to determine the odds of sustaining a concussion with our main predictor being processing speed (high or low) adjusted for the effects of age, sex, and prior number of concussions. Three hundred ninety junior high soccer players ages 10 to 15 with a baseline score for ImPACT. Risk of sustaining a concussion was used as the outcome variable. Those with slow processing speed had a visual motor composite score of ≤19.92, those with fast-processing speed had a score of ≥46.20. Athletes with slow processing speed were younger (13 vs 14 years; P < 0.001) and more likely to be male (57% vs 49%; P = 0.014). After adjusting for the effects of age, sex, and prior concussions, there was no significant difference in the odds of sustaining a concussion between groups (aOR 1.01; 95% CI, 0.99-1.04). Despite previous research showing that slow processing speed is a risk factor for musculoskeletal injuries during sports, our study suggests that processing speed is not associated with the risk of sustaining a concussion among junior high school soccer players.



#15 Determining the hip joint isokinetic muscle strength and range of motion of professional soccer players based on their field position

Reference: PeerJ. 2022 Oct 26;10:e14000. doi: 10.7717/peerj.14000. eCollection 2022.

Authors: Ali AlTaweel, Shibili Nuhmani, Mohammad Ahsan, Turki Abualait, Qassim Muaidi

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Summary: Soccer players' physical and physiological demands vary based on their field position. Although the hip joint has an important role in soccer, little information is available about the strength and flexibility of the hip joint based on player positions. Therefore, this study aims to investigate the differences in muscle strength and flexibility of the hip joint of professional soccer players based on their field position. Ninety-six professional soccer players from Saudi Arabia were divided into four groups (goalkeepers, defenders, midfielders, and attackers), with 24 participants in each group based on their field position. The Modified Thomas test was used to measure the hip extension range of motion (ROM), and muscle strength was assessed by an Isokinetic dynamometer. There were no statistically significant differences in the isokinetic strength at the hip joint movements between goalkeepers, defenders, midfielders, and attackers (p ≥ 0.05). At the same time, there was a significant difference between groups in the hip extension ROM (p ≤ 0.05). according to different player positions. Post hoc tests reported significant differences between goalkeepers and defenders (p ≤ 0.05), midfielders (p ≤ 0.05), and attackers p ≤ 0.05). At the same time, there were no significant differences between defenders and midfielders (p ≥ 0.05), defenders and attackers (p ≥ 0.05), and midfielders and attackers (p ≥ 0.05). Even though there was no significant difference in isokinetic strength, there was a significant difference in hip extension ROM among players based on field position. This study may help coaches and trainers to recognize the strengths and weaknesses of players and design training programs to rectify the weaker components and improve players' performance in different playing positions.


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