|Year : 2013 | Volume
| Issue : 2 | Page : 90-97
The incidence, severity and etiology of injuries in players competing in the Saudi Premier League between 2010 and 2012
Mubarak Almutawa1, Mark Scott2, Keith P George2, Barry Drust2
1 Saudi National Football Team, Prince Mohammad Bin Naïf Medical Centre, KFSC, Riyadh, Saudi Arabia; Football Exchange, Research Institute for Sport and Exercise Sciences, Liverpool John Moores University, Liverpool, L3 3AF, UK
2 Football Exchange, Research Institute for Sport and Exercise Sciences, Liverpool John Moores University, Liverpool, L3 3AF, UK
|Date of Web Publication||20-Dec-2013|
Football Exchange, Research Institute for Sport and Exercise Sciences, Liverpool John Moores University, Liverpool, L3 3AF, UK
Purpose of the Study: The purpose of this study is to evaluate the incidence of injuries sustained by Saudi Premier League clubs over two consecutive competitive seasons (2010/11 and 2011/2012. Specifically, we compared injuries sustained in match play versus training and we provide an initial exploration of the impact of environmental conditions on match play injuries. Materials and Methods: A total of 198 players were studied (mean ± SD; age 28.2 ± 1.8 year; height 177.3 ± 1.0 cm; weight 71.6 ± 1.4 kg; body mass index 22.8 ± 0.3 kg/m 2 ). A prospective cohort design was used to investigate the injuries that occurred in training and match play. Injury definition was set at "any injury that resulted in medical attention or assessment, irrespective of the impact on time lost from subsequent football activity." Club medical staff recorded injuries and match play and training exposure on a standard proforma. Ambient temperature and relative humidity were recorded for all games. Results: A total of 617 injuries were recorded at an incidence rate of 8.3 injuries/1,000 h player exposure. 355 injuries were recorded during training (5.5/1,000 h) and 262 during match play (29.7/1,000 h). For total injuries as well as subcategories of severity, location, type, recurrence, diagnosis and the role of contact, the incidence rate was substantially higher with match play. Post-hoc categorization of ambient weather suggests a greater risk of match play injury in hot (>30C) and dry (<50% relative humidity) conditions. Conclusion: This study detailed the total "medical-attention" injury load presented by professional football players to medical teams in 6 Saudi Premier League Clubs. Injury incidence was higher in match play than training and match play. This data provisionally indicates that injuries may be mediated by the prevailing environmental conditions.
الغرض من هذه الدراسة هو تقييم نسبة حدوث الإصابات التي تعرض لها لاعبي أندية الدوري الممتاز السعودي خلال فترة موسمين من المنافسات ( 2012 . 2010م ) وبشكل خاص إجراء مقارنة بين الإصابات التي تعرض لها اللاعبون أثناء المباريات مقابل التدريب واستقصاء أولي عن تأثير الظروف البيئية قبل الأنخراط في المباريات.
الطرق : تم دراسة 198 لاعباً ( متوسط أعمارهم 28,2 ± 1,8 سنة ) ( الطول 177,3 ± 1 سم) الوزن (71,6 ± 1,4 كغ) (مؤشر كتلة الجسم 22,8 ± 0,3 كغ/متر المربع) تم وضع تصميم أترابي استباقي لاستقصاء الإصابات التي حدثت في التدريب وأثناء اللعب. تم تحديد الإصابة على أنها " أي إصابة احتاجت إلى فحص أو عناية طبية بغض النظر عن تأثيرها على الوقت المفقود من نشاطات كرة القدم التالية سجل الفريق الطبي للنادي الإصابات أثناء التدريب وإثناء المباريات بطريقة أولية تقليدية ، مع تسجيل درجة الحرارة المحيطة والرطوبة النسبية أثناء جميع المباريات.
النتائج : من مجموعه 617 إصابة تم تدوين 8,3 إصابة لكل 1000 ساعة تعرض للاعب ، 355 إصابة دونت خلال التدريب (5,5 لكل 1,000 ساعة) و262 إصابة خلال المباريات (29,7 لكل 1000 ساعة) في جميع الإصابات وأيضاً في الفئات الفرعية من ناحية شدة الإصابة، مكانها، نوعها، تكرارها، تشخيصها ودور التلامس وكانت نسبة الإصابات أعلى بكثير أثناء لعب المباريات. أن الطقس الحار عنصر خطورة يكثر من فرص الاصابة عندما تمارس الرياضة في الطقس الحار والرطب.
الاستنتاج: أوضحت هذه الدراسة تفاصيل الإصابات التي احتاجت إلى مباشرة طبية للاعبي 6 أندية سعودية للمحترفين في الدوري الممتاز. كانت نسبة الإصابة أعلى أثناء المباريات. تشير هذه الدراسة إلى أن الإصابات قد تكون نتيجة الظروف البيئية السائدة.
Keywords: Contact, overuse, severity, soccer, weather
|How to cite this article:|
Almutawa M, Scott M, George KP, Drust B. The incidence, severity and etiology of injuries in players competing in the Saudi Premier League between 2010 and 2012. Saudi J Sports Med 2013;13:90-7
|How to cite this URL:|
Almutawa M, Scott M, George KP, Drust B. The incidence, severity and etiology of injuries in players competing in the Saudi Premier League between 2010 and 2012. Saudi J Sports Med [serial online] 2013 [cited 2019 Feb 18];13:90-7. Available from: http://www.sjosm.org/text.asp?2013/13/2/90/123388
| Introduction|| |
Injuries to football players can impact individual health as well as presenting an economic burden to the individual and team.  The nature of the burden is often best represented by football injury registry data that is useful for assessing trends and injury "loads" that confront players, coaches and medical support staff. ,
Because of the global popularity of professional football and the diverse countries in which the game is played, region or country-specific football injury registry data are likely to be informative related to the burden placed on medical support services. Football injury registry data from professional leagues has been collected in a range of countries around the globe (e.g., UK, 31; Finland, 20). Waldén et al.  reported injury data on players from various countries involved in Union of European Football Associations Champions League and International Matches during a full football season. Interestingly the risk of a match-related injury was variable between countries and significantly higher in English and Dutch teams (41.8) than in the teams from France, Italy and Spain (24.0; P = 0.008). Such data supports the idea of a regional impact upon football injury statistics.
To date, limited football injury data has been collected in Asia  with no systematic collection of injury information undertaken in Saudi Arabia. This presents a gap in the local knowledge that is pertinent to address. Developing an injury database related to the Saudi Arabian Premier Football League will serve as a valuable reference for medical staff and officials to review the injury history of players, look for emerging injury trends, assess causative factors and where relevant use this data to introduce appropriate interventions.
If patterns of injury are as suggested,  country or region-specific then it is also pertinent to investigate what factors may mediate region-to-region or country-to-country differences in injury data. This issue is not well-explored in the scientific literature, but some suggestions have included differences in ability and physical profiles of players, individual approaches to training and match loads and alterations in environmental conditions. ,
When considering football injury patterns in Saudi Arabia a number of potential issues of interest arise. Firstly, we will compare injury data from training compared to competitive match play. Higher injury prevalence in match play is widely reported, ,,,,,,, although regional differences in training practices are rarely taken into account in such data. An interesting aspect of Saudi Football is that formal training sessions tend to be quite short and largely technical or tactical. Secondly, Saudi Arabia has extreme ranges of environmental conditions in which professional matches are played. Games in Riyadh are commonly played in hot and dry conditions compared to Jeddah where humidity is high. Environmental extremes may mediate changes in physiological load, fatigue and cognitive function all of which may impact injury risk.  Few previous studies have investigated the association between football injury data and prevailing environmental conditions.  Woods et al.  described a greater injury risk in pre-season when warmer temperatures and harder ground conditions occur although no formal link to temperature and humidity were assessed directly. The varied and often extreme environmental conditions in Saudi Arabia would seem to provide a unique opportunity to provide an initial exploration of the impact those environmental conditions on football injuries during match play.
Consequently, the overarching aim of this study was to evaluate the incidence, severity and nature of injuries in professional Saudi Arabian Football players competing in the Saudi Premier League in 2010/11 and 2011/2012. We sought to compare injury data during training and competitive match play as well as assessing the impact of weather variation on match play injury data. We hypothesize that a higher injury rate occurs during match play compared to training and that higher temperatures and/or humidity's will be associated with higher injury incidence during match play.
| Materials and Methods|| |
We recruited 198 Professional Football Players at 6 Saudi Premier League Clubs and recorded all injury data over two consecutive competitive seasons (2010/11 and 2011/2012). All 198 Professional Players (mean ± SD; age 28.2 ± 1.8 year; height 177.3 ± 1.0 cm; weight 71.6 ± 1.4 kg; body mass index 22.8 ± 0.3 kg/m 2 ) gave written informed consent. The Saudi Premier League, Saudi Football Association (FA) and individual clubs provided gatekeeper agreement to complete the study. Local institutional ethics approval was also obtained prior to the study. The only inclusion criterion was selection to a club's squad for a competitive season. There were no exclusion criteria, as players with current injuries were not playing or training until appropriately rehabilitated/recovered.
A prospective cohort design was used to investigate injury data in all 6 clubs. Over the study period of two competitive seasons' data was collected related to injuries, training and match-play exposure as well as environmental conditions at all matches. Match play exposure included all Saudi Premier League games, all Saudi Cup Matches, Asian competition games and practice/warm-up matches.
The Medical Assessment and Research Centre of Federation Internationale de Football Association (FIFA) support the use of the standard player information, injury reporting and exposure tools and these were adopted for the current study.  For data collection an injury was defined as "any complaint that resulted in a medical evaluation of a player, irrespective of whether this lead to time lost in training or match play." This "medical attention" definition has been described and supported in a FIFA consensus statement  and this approach was adopted as we felt this best reflected the total injury load presented to Saudi Premier League team medical staff.
Data were collected by medical staff located within each professional club on a daily basis. Information was recorded and coded as follows in relation to a number of injury characteristics as described by Fuller et al.  For injury severity, we adopted the following definition and categorization; 0 days absence from football activity (none) versus 1-3 days absence from football activity (slight) versus 4-7 days absence from football activity (minor) versus 8-28 absence from football activity (major) versus 28+ days absence from football activity (severe). Injury location was first categorized as upper body versus lowers body. Lower body injuries were further categorized; hip and groin versus thigh versus knee versus lower leg and Achilles tendon versus ankle versus foot and toe. Upper body injuries were further categorized as; shoulder/cervical versus upper arm versus elbow versus forearm versus wrist versus hand/finger/thumb. Injury type was categorized as; fractures/bone versus sprain/ligament versus meniscus/cartilage versus muscle versus tendon versus bruise versus abrasion/laceration versus others. If injury history data allowed the injury was also defined as recurrent (same type, site and player); yes versus no. The cause of injury was coded as; overuse versus trauma. Finally, all injuries were coded in relation to contact (player or ball) as; yes versus no. All staff involved in the project agreed to comply with the requirements of the investigation following discussion with the Saudi FA. The recording of injuries at each club was reported to the principal investigator on a weekly basis. All medical staff at the Premier League Clubs involved in the investigation completed a comprehensive training program with the lead author to familiarize them in the use of the injury report forms. A trial period of 4 weeks was used to evaluate the consistency and feasibility of injury data collection at each club with support from the principal investigator, to explain the way in a clear and well-applied in practice even mastered the medical team for each club.
All exposures to the training (group) and matches (player-by-player) were recorded during the data collection period by the medical staff at each club and passed to the lead author. A total of 2823 training sessions were completed by the 6 Premier League teams across the two seasons studied. The 6 teams completed 534 preparation and competitive games over the two seasons. Exposure data was then calculated as; 528,660 min (match play), 3,908,520 min (training) and 4,437,180 min (total exposure).
For ease of data interpretation we defined, post-hoc, 4 specific weather groupings; hot and dry (temperature ≥30°C and relative humidity <50% with no rain), hot and humid (temperature ≥30°C and relative humidity ≥50%), cold and dry (temperature <30°C and relative humidity <50% with no rain) and cold and humid (temperature <30°C and relative humidity ≥50%). With available weather data we were able to calculate total match exposure to each weather condition that then allowed the calculation of injury incidence. Further we assessed the incidence of injury severity, location, type and circumstance in relation to the prevailing weather conditions. Exposure to prevailing weather conditions for match play was 112,850 min (hot and dry), 291,060 min (hot and humid), 23,760 (cold and dry) and 106,920 (cold and humid).
We collated data and reported, descriptively, the frequency of injuries as well as injury incidence per 1,000 h of player exposure. Initially, we cross-tabulated data for all injuries that occurred in training versus match play against severity, location, type, recurrence, diagnosis and involvement of contact. Secondly, with respect to match-play injury data we cross-tabulated prevailing environmental conditions with injury severity, location, type and involvement of contact. Due to the quasi repeated measures design employed the assumption of independence of observations (players and injuries) could not be met; therefore, inferential statistics (e.g., Chi-squared analyses) were not conducted in this study.
| Results|| |
Exposure and overall injury incidence
Players' exposure, injury frequency and incidence for training, match and overall football play are presented in [Table 1]. A total of 355 injuries were recorded during training and 262 during match play. Given the greater total training time exposure the injury incidence rate was only 5.5 (per 1,000 h of exposure) for training compared to 29.7 (per 1,000 h of exposure) for match play. Total injury incidence across all football activity was 8.3 injuries (per 1,000 h of exposure).
|Table 1: Training, match and total player exposure, injury frequency and injury incidence|
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The majority of injuries that occurred in both training and match play resulted in no loss of training time or match play [Table 2]. The most severe injuries (requiring greater than 28 days away from football) were relatively infrequent (n = 29). For all levels of injury severity incidence data was higher (c. 10-fold) in match play compared to training.
|Table 2: Frequency and incidence data for severity of injury during training and match play|
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Most injuries involved the lower body (n = 491) irrespective of training or game play [Table 3]. Thigh injuries were the most frequent lower body injury during training, whilst knee, thigh, lower leg and ankle injuries had similar frequencies in match play. For the upper body shoulder and hand injuries were more common. Incidence levels for both upper and lower limb injuries were 5-10 folds higher in match play compared to training.
Injury type categories were, by necessity, broad [Table 4]. Muscle and tendon injuries were the most common injuries in both match play (n = 253; 49.6/1000 h exposure) and training (n = 320; 5/1,000 h exposure). Fractures and bones stress were the least frequent injuries. Incidence levels for all injury categories were substantially higher with match play.
|Table 4: Frequency and incidence data for diagnosis of injury for training and match play|
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Data for injury recurrence are reported in [Table 5]. It is important to note that the total number on injuries is reduced due to cases where a full injury history was unclear. Recurrent injuries were less frequent than new injuries in both training and match-play. Again injury frequency was higher during match play by a factor of 5-10.
|Table 5: Frequency and incidence data for injury recurrence during for training and match play|
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Overuse injuries were slightly more frequent than injuries due to trauma [Table 6]. Whilst more injuries in both categories occurred during training because of the greater exposure time to training, the incidence of both types of injury was higher in match play.
|Table 6: Frequency and incidence data for overuse and trauma injuries during for training and match play|
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The frequency and incidence were similar between those that involved contact (n = 283, 3.6/1000 h) and those that didn't [n = 328, 4.4/1,000 h; [Table 7]]. The incidence of both categories was higher in match play by a factor of 3-10.
|Table 7: Frequency and incidence data for contact and non‑contact injuries during for training and match play|
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Of the 262 injuries in match play 135 occurred in hot and dry, 27 in hot and humid, 61 in cold and dry and 29 in cold and humid conditions. Data for injury severity, location, type and contact in all weather conditions is contained in [Table 8],[Table 9] and [Table 10]. The pattern for most data was that injury incidence rates were highest in hot and dry weather conditions. The lowest injury incidence data were in hot and wet conditions.
|Table 8: Frequency and incidence data for match play injury severity in different weather conditions|
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|Table 9: Frequency and incidence data for match play injury location in different weather conditions|
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|Table 10: Frequency and incidence data for match play injury type in different weather conditions|
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| Discussion|| |
We completed detailed injury data collection in 198 professional football players at 6 Saudi Premier League Teams over two consecutive competitive seasons (2010/11 and 2011/2012). The main findings were (1) a total of 617 injuries reflect the "medical-attention" and treatment load in the Saudi Premier League and allow comparison with other regions around the globe, (2) a higher overall injury incidence (as well as in relation to all sub-categories) was noted during match-play compared to training and (3) in an initial exploration an impact of prevailing weather conditions was noted with the highest injury incidence rates occurring in hot and dry match conditions.
The regional context
The total injury frequency was 617 over two competitive seasons at an incidence rate of 8.3/1,000 h of player exposure. Few studies of professional football leagues around the globe have documented total injury incidence rates with the same approach to data collection and injury definition.  Ekstrand et al.  reported an overall injury incidence in Swedish professional players of 8.0/1,000 h and exposure, which is remarkably similar to the current study.
The injury incidence during match-play in the current study was 29.7/1000 h of player exposure. This is slightly higher than rates reported for elite players in Sweden and European clubs, , (14, 19.6 vs. 21.5; 3, 17.0), but similar to other data reported from Scandinavia (16, 27.5; 20, 28.2 and 26.2 in Sweden and Denmark, respectively), the UK (21, 27.7) and across a range of European countries.  The injury incidence during training in the current study was 5.5/1,000 h of player exposure. This is slightly higher than data reported for elite players in Sweden (14, 2.9; 16; 3.5; 3, 1.8) and the UK (21, 3.5), but again similar to that reported by Waldén et al.  and lower than other data from Sweden (20, 11.8).
A number of previous studies of male professional footballers, from different countries, have reported data related to injury severity, location, type etc. Some evidence of country-specific variance has been noted. For example, Waldén et al.  observed that severe injuries were more common in English and Dutch teams compared to other European nations. The data presented in this study are however, generally consistent with previous findings; (1) most injuries are minor with limited time lost to play or training (e.g., 23), (2) injuries to the lower limb are more frequent (e.g., 6) and (3) muscle injuries (e.g., contusions, strains) are the most common type of injury (e.g., 23). The nature of the injury pattern in the current study; minor severity, mostly lower limb and involving the musculature simply reflects the nature of football training and competition and is broadly representative of football in most groups, countries and levels of play. ,, Around the globe the consensus from available information is that player contact is the major cause of injury. ,,, Contact was reported to account for 82%  and 87%  of all match injuries. In the current study contact was associated with only 46% of the match and training injuries. Whilst this balance is similar for specific categories of injuries in past work (e.g.; severe injuries  ), there is the possibility that the lower frequency of contact injuries in Saudi Professional Football could reflect a regional difference in tactical approach to training and match play that doesn't emphasize the contact aspects of the game.
The small variations in injury incidence data in any study could reflect subtle variations in age and level of play as well as differences in research design, or the quality of the exposure data and injury registration. Despite this, the overall picture is that total injury load in professional footballers in the Saudi Premier League as well as sub-categorizations (match vs. training, severity etc.) are consistent with injury data reported in other regions around the globe. This suggests that the impact of region/country has little effect on overall injury load to players, teams and medical staff when professional male players are studied at the elite or professional level and maybe reflects globalization of the game in terms of the players (physical capacity, technical skills, preparation, nationality), coaching staff (nationality, tactical and technical approaches), medical staff (transfer of training and medical skills), officials (standard rules) as well as playing conditions (pitch preparation and care).
Comparison of match play and training
In the current study, match play injury incidence (overall as well as in relation to severity, location, type, recurrence, mechanism, contact) was considerably higher than during training. This data supports previous studies completed in a range of countries and different cohorts (e.g., 39). For example, Hδgglund et al.  reported injury incidence in match play (28.2 vs. 26.2/1,000 h in Sweden and Denmark, respectively) that was higher than during training (11.8 vs. 6.0/1,000 h). Hawkins and Fuller,  reported an overall injury frequency rate of 3.5/1,000 h during training and 27.7/1,000 h during match play in England. Study-to-study variance in training and match play injury data is to be expected. For example, in two single seasons studies of professional football players Nielsen and Yde  reported a match injury incidence of 19/1,000 h compared to Arnason et al.  who observed 35/1,000 h of match play. Both of these studies relied on the coaching staff to time and report exposure data. Clearly between study differences in data collection methods could explain some of the between study variance in outcomes. Even in studies where sub-categories of injuries are studied or incidence data was reported as a percentage of total injuries the pattern is still consistent. Ekstrand and Gillquist  reported that two-thirds of traumatic injuries occurred in match play.
The explanation of the higher injury incidence in match play compared with training is likely multi-faceted and combines the greater physiological and psychological stress of match-play. The change of approach from training to match play is marked (greater level of competitiveness) and players often play at the edge of their physical and cognitive limits. Making subtle tactical and technical decisions in periods of high stress and/or fatigue may result in greater exposure to injuries. At a very simple level, there is likely to be more contact between players during match play compared with training (where an element of injury prevention is pervasive to protect players for matches). It has previously been suggested that training incidence rate is highly dependent on training methods and coaching attitudes to the intensity of training and the contact that is permissible between players during training sessions.  In Saudi Arabia, the focus on technical and tactical skills in training likely explains the lower injury incidence, but this does not seem to be at odds with data from other professional teams around the globe.
The impact of weather conditions
In the current study, we employed an initial exploration of weather conditions and observed that most of the injuries during training occurred in hot and dry (n = 157, 2.4/1,000 h match exposure) compared with hot and humid (n = 27, 5.2), cold and dry (n = 61, 12.0) and cold and humid (n = 29, 5.7). It would seem that a hot ambient temperature with a low humidity produces the greatest chance of a football injury in Saudi Arabian Professional Footballers. There is limited data studying the direct changes in match-play environmental exposure on football injuries and we can only speculate as to why risk is enhanced in hot and dry environmental conditions, but lowered in hot and humid conditions, where the physiological stress might be at its highest. An increased risk in hot and dry conditions could be a combination of the thermal stress on players physiological status and decision making skills allied to harder playing surface conditions when dry. Some prior work has reported more injuries in dry than wet weather, most likely because of its effect on the quality of the playing surface.  Pitch hardness data was not collected systematically to underpin this hypothesis but may be worth investigating in future studies.
Somewhat surprisingly, the lowest injury incidence occurred in hot and wet (humid) conditions). It may have been postulated that these weather conditions may have prompted higher injury incidence because of the clear thermal strain induced by exercise in hot and humid environments where heat loss owing to sweating is limited and heat storage can results in hyperthermia and dehydration. The opposite effect, lower injury incidence, might be due to an a priori knowledge of the potential environmental stress that results in both technical and tactical alterations to game play. Specifically, in hot and humid environments the game often "slows down" to allow players to cope.  A reduction in game intensity, allied to other tactical changes may reduce the chance of injury. We did not collect match analysis data (e.g., Prozone) alongside injury and exposure data that would have illuminated any tactical changes allied to ambient weather conditions and this could be studied in the future.
Some limitations and areas for future research should be noted. The research was limited to only 6 of the 14 Saudi Premier League Clubs and as such do not represent the total injury load in the Premier League in Saudi Arabia. Although, we provided training for medical staff at all clubs we cannot be entirely sure that injury reporting was totally consistent. Minor club-to-club bias or differences may have altered injury data, but we feel that this would be marginally important given the similarity in club set-up, training style and match exposure across Saudi Arabia. We have alluded to on-going research opportunities within the text; however, having set this study up as a baseline for football injury data collection and interpretation in Saudi professional football there are other avenues to explore. For example, future research could study level of play (Premier League vs. National Team) as a factor relevant to injury prevalence.
Football Exchange, Research Institute for Sport and Exercise Sciences, Liverpool John Moores University, Liverpool, L3 3AF, UK,
This study detailed the total "medical-attention" injury load presented by Professional Football Players to medical teams in 6 Saudi Premier League Clubs. The injury incidence data reported for both match and training play were comparable to data from professional footballers in different parts of the world. Whilst most injuries were minor the breadth of injury severity, location and type presents a challenge to all medical teams. Injury incidence was generally higher during the match play compared with training and this has implications for the size and nature of medical support staff available at training and match play. In an initial exploration injury incidence rates were highest in hot and dry environmental conditions, but lowest in hot and wet conditions. Continuing work is needed to fully appreciate and understand the etiology of football injuries in Saudi Arabia.
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[Table 1], [Table 2], [Table 3], [Table 4], [Table 5], [Table 6], [Table 7], [Table 8], [Table 9], [Table 10]