– Written by Roald Bahr, Bahar Hassanmirzaei, Montassar Tabben, Mokhtar Chaabane, Souhail Chebbi, Raouf Nader Rekik, Ramadan Daoud, Yorck Olaf Schumacher, Karim Chamari, Qatar
INTRODUCTION
The bad news: Football, at all levels, carries a substantial risk of injury—some severe and some even career-threatening. The good news: Many injuries can be prevented—even the serious ones.
If you do nothing - what can you expect?
Typically, a team will suffer one injury every second match and one anterior cruciate (ACL) injury – a serious, career-threatening injury – every two seasons1. Male teams have had more injuries than females in the past2, but an unfortunate consequence of the rapid development of female football is that the injury risk also seems to catch up. Female players are also at a 3-4 greater risk of ACL injuries than men. Although the overall risk is somewhat lower in younger players, with growing athletes, it is important to be aware of apophysitis and other injuries to the growth plates.
As a practitioner, you need to be aware of the typical injury pattern in football. Figure 1 gives a good indication of what you can expect. Acute injuries dominate over overuse injuries. This pattern is also your guide to preventing injuries; acute knee (especially ACL), thigh (hamstrings), groin, and ankle injuries should be a priority, as Figure 1 clearly illustrates.
Can you do something about it?
Fortunately, there are also patterns to how injuries happen—they are often referred to as internal and external factors. Some external factors are difficult to control; football is a complex game with frequent player-to-player contact, which may cause an injury. Internal factors are player traits, such as strength or coordination. Some of these are related to injury risk—these can be trained to shrink injury risk3. Evidence shows that targeted exercise programs can prevent at least half of all sports injuries (e.g., FIFA11+, Knäkontrol)4-7. Specific exercises focusing on specific injury types show even better results: The Nordic Hamstring Exercise lowers the risk of hamstring muscle injuries by 57-70% and even more in players with a recent injury8. Another example is groin problems: The Adduction Strengthening Programme, based on a tailored eccentric exercise, reduces this risk substantially9.
Other factors also affect injury risk; field conditions, equipment, fitness and psychological factors are examples10. Many sports-related health problems, not just injuries, can be avoided if players and their coaching staff routinely adopt well-established health-promoting behaviors: healthy training patterns, healthy diet/sleep, managing anxiety and stress, and avoiding interventions that can cause more harm than good11.
Injury prevention programs are effective—they reduce the risk of injury and shrink healthcare costs. In the next chapter, we describe what you can do to prevent injuries in your team.
EXERCISE-BASED INJURY PREVENTION PROGRAMS
Warm-up programs
Structured exercise programs prevent injuries in general. They are often designed to be used as warm-up programs; this makes it easier to include them in the team’s training routine.
One specific target for all programs designed for football is ACL injuries, for reasons outlined above. Excessive valgus stress to the knee is one of the major risk factors. So, controlling movements that cause excessive dynamic valgus of the knee is a key part of any ACL injury prevention program12,13.
FIFA (Fédération Internationale de Football Association) is promoting the FIFA 11+ program as a prevention program, targeting “the big 4”: the knee, hamstrings, groin, and ankle6. The 11+ program combines a series of 15 structured warm-up exercises (see Figure 2): core stabilization, eccentric thigh muscle training, proprioceptive training, dynamic stabilization, and plyometric exercises. Each of the strength, plyometrics, and balance exercises has three levels of challenge to allow players to progress. Performing these with proper postural alignment (“knee over toe”) is a key element emphasized for all movements from start to end. One key feature of this program—to make it appropriate to be used as a warm-up program—is that it starts and ends with a running exercise to fully prepare the players for activity with the ball. For the same reason, it works equally well before a game. The 11+ program, with videos of all exercises, is available online14. (Online source 1 - https://fit4football.co.nz/)
The 11+ program lowers injury risk substantially. Female teams using the program can expect a 29% reduction in overall injury rate and an even more substantial effect on severe injuries6. It also works well in male football. When the 11+ program is implemented correctly, male teams also decrease the overall injury rate (46%) and the rate of ACL injuries (58%)15,16. Teams using the program correctly, 2-3 times per week during the pre-season and at least once weekly during the season, have better results than inconsistent users.
The impressive effects of the 11+ program have also led FIFA to develop specific warm-up/prevention programs for kids (FIFA 11+ for kids), referees (FIFA 11+ for referees), and for goalkeepers to prevent shoulder injuries (FIFA 11+S)17-21, recognizing that their injury risks and patterns are different.
The 2019 FIFA Women’s World Cup hailed “the competition’s best generation of goalkeepers ever” and raised attention on their health. Their role differs from other players, requiring a specific warm-up program meeting their demands. This program, the FIFA 11+ shoulder program, 11+S, provides guidance on a warm-up for adolescent goalkeepers with minimal equipment needed17. (Online source 2 - https://www.youtube.com/playlist?list=PLCGIzmTE4d0gA--gAWtkIcwObk3IfAJPV).
Another well-documented multi-component program is Knäkontroll (Knee Control), a neuromuscular warm-up program based on six exercises targeting knee control and core stability: one-legged knee squat, pelvic lift, two-legged knee squat, the bench, the lunge and jump/landing technique7. Similar to the 11+ program, exercises progress from basic to more difficult (4 levels) and are preceded by low-intensity running. This program has been shown to reduce the risk of ACL injuries by 64% in young adolescent girls. An extended version of the Knee Control program, with the same six main exercises but with more exercise variations to make it more attractive, reduces the risk of lower extremity injuries in general by 26%22,23.
Strength training programs
In addition to the multicomponent warm-up programs 11+ and Knäkontroll, specific strength-training programs are designed to target specific injuries, mainly based on eccentric exercises. The hamstrings are one example since muscle strains in the posterior thigh are the most common injury in football. Hamstring injuries also often recur, again and again. The exercise best studied and most commonly used to prevent hamstring strains is the Nordic Hamstring Exercise. This exercise is also included in both the 11+ and Knäkontroll programs. (Online source 3 - https://utbildning.sisuforlag.se/fotboll/tranare/spelarutbildning/knakontroll-engelska/)
The Nordic Hamstring Exercise involves kneeling on a pad (for more knee comfort) and lowering the body forward under control. At the same time, the ankles are held in place by a partner or an immovable object. The hamstring muscles are loaded eccentrically by leaning forward from the knee, not the hip24. A 10-week program of Nordic hamstring exercise training improves eccentric strength by 11% and also changes muscle architecture favorably25. Teams using this exercise reduce their risk of hamstring injuries by as much as 68% and re-injuries by an even more impressive 85%26,27. But note that player compliance is critical; players with low compliance with the NHE exercise are at greater risk compared to those adhering with the prescribed program27.
Another preventive strengthening exercise-based program targets groin injuries, another problematic football injury. Groin injuries are most often located in the adductors, accounting for about two-thirds of all28 and weak hip adductors increase groin injury risk. The Copenhagen Adduction Exercise increases hip adduction strength29; an 8-week trial with this exercise led to 35.7% gains in eccentric hip adductor strength and a 20.3% increase in eccentric hip abductor strength30. Even more important is that a training program based on this exercise, the Adductor Strengthening Program, reduces the risk of groin problems in football players by 41%9. Like the Nordic hamstring exercise program, the Adductor Strengthening Program calls for training 2-3 times a week during the preseason and one weekly maintenance session in-season. And in the same way as the other programs, teams training consistently have better results than inconsistent users.
Note that the Copenhagen Adduction Exercise has not yet been added to FIFA 11+, so this is something you should consider.
Other exercise-based programs
Multi-component programs based on a variety of movement patterns are more efficient than single-component programs in reducing overall injury risk. Such programs and movements can target different neuromuscular qualities such as core and dynamic stability, static and dynamic balance, flexibility, plyometric strength, impact force control during landing after a jump, control of valgus and varus stresses on the knee and ankle, pelvic control. In general, all the programs based on various forms of neuromuscular training are effective for ACL injury prevention32-34.
It is unknown which component is the most important, but balance and core stability training are the most popular. They are among the five most common injury prevention exercises Premier League clubs use and the three most commonly used exercises for clubs in the UEFA Elite Clubs study, which includes the Champions League clubs35,36.
Players with functional ankle instability, which is not uncommon after an ankle sprain, display deficits in postural control and reflex stabilization37. Players with greater sway when they balance on one leg are at greater increased risk for ankle sprains38. Balance training reduces the risk of ankle sprains by about 50%, but this effect is only seen in players with a recent sprain (within the last year). Balance training should therefore always be considered for players with a history of ankle sprains and is the key component of the rehabilitation program after a sprain. Balance exercises should get progressively more difficult, starting on a stable surface, moving to softer surface and finally to a foam mat, wobble board or sand, and gradually also introduce perturbations and distractions. Players should also be exposed to a range of conditions, such as landing from various directions, both with and without perturbations.
Plyometric exercises (exercises using speed and force of different movements to build muscle power) are thought to be highly relevant. They perfectly match the multifaceted nature of the physical demands in football, improving performance through greater maximal strength, sprinting speed, shooting power, endurance, jumping ability and change of direction in players of all ages39-41. Plyometric exercises enhance joint awareness and postural control and in this way can improve lower extremity control and prevent injuries42. This is also why plyometrics reduce the risk of first-time noncontact ACL injuries43.
Traditionally, stretching has been advocated as a way to prevent injuries. Static stretching improves musculotendinous stiffness However, while static and dynamic stretching modalities affect performance and range of motion positively, no studies show any effect on injury risk44.
NON-EXERCISE-BASED INJURY PREVENTION MODALITIES
Exercise programs are not the only way to prevent injuries. Other factors can also play an important role. In this section, we will discuss some of them.
Sleep
Sleep is associated with the risk of injury. Players who sleep less than 7 hours daily have an increased risk of injury compared to those who sleep longer. If this sleep deprivation is sustained for at least 14 days, the risk of musculoskeletal injury is 1.7 times greater. However, we do not know if sleep loss predisposes the athlete to specific musculoskeletal injuries45. Poor sleep quality also affects performance, increases the risk of injury46 and negatively affects recovery after training. Following a sleep hygiene protocol can be helpful in reducing injury risk.
Nutrition, hydration, and supplements
Nutrition is essential for improving the health, performance, and recovery of athletes. A player’s hydration deficit at the beginning of a match can compromise performance47. It is important to maintain a fluid balance before, during, and after exercise, as it will minimize the risk of hyperthermia and exertional heat illness48.
Whether sports supplements have any role in injury prevention is not known and there is always the risk of supplements contamination and doping rule violations for athletes. The complexity of nutrition research and potential conflicts of interest from sponsorship by industry make research in this field particularly vulnerable to bias49. More studies involving humans, specifically athlete populations, are needed to understand if supplements give benefits for the prevention of injury or recovery of injured athletes50.
Training load
Athletes participating in elite sports are exposed to high training loads. Poor load management represents a major risk factor for injury. Insufficient respect for the balance between loading and recovery can lead to prolonged fatigue, abnormal training responses (maladaptation), and an increased risk of injury and illness51.
High loads can positively or negatively influence injury risk in athletes. Load must always be prescribed on an individual and flexible basis. Athletes respond significantly better to small increases (and decreases) than more significant loading fluctuations. Regular athlete monitoring is fundamental to ensure appropriate levels of external and internal loads and, thus, to maximize performance and minimize the risk of injury52-54.
Taping and bracing
The use of tape and brace to prevent musculoskeletal injuries or re-injuries is common in sports. Taping and bracing are individually linked to an approximately 50% reduction in ankle sprains, but like balance training, this effect is limited to players with a recent sprain (within the last 12 months). We do not know which is best, taping or bracing. Bracing is arguably the cheaper option but taping is better tolerated by football players who want optimal ball control55.
Football shoes
Footwear is an integral piece of protective equipment. Players should select footwear based on comfort, traction and stability, while protecting from injury. Shoes should fit well and be wide enough to accommodate the foot. Natural leather uppers will “shape’ around the foot, while synthetic materials will not56,57.
The combination of shoe type, outsole groups (studs) and type of grass affect rotational traction, which is linked to increased lower extremity injury risk. Players should have multiple shoes with varied outsole configurations available. This way – depending on the pitch conditions – they can pick the shoes that provide optimal traction for performance, yet not too high traction at the shoe-ground interface since this increases the risk of injury, especially to the ligaments of the knee such as the ACL58,59. Clinicians should educate players on these aspects, as their choices might be more because of shoe design and marketing than shoe performance.
Shin guards
Shin guards effectively prevent minor (contusions) and severe (fractures) injuries to the lower leg60 and are mandatory during football matches since 201561. The main function of shin guards is to protect the soft tissues and bones in the lower extremities from external impact, provide shock absorption and facilitate energy dissipation62. However, they are only effective if they fit the player well and are worn properly. Unfortunately, some players use the smallest size shin guards possible, exposing a large portion of their shins to injuries. As for shoes, clinicians should educate their players on the proper utilization of protective equipment.
THE FUTURE OF INJURY PREVENTION IN FOOTBALL
Building an injury prevention program for a team requires careful planning – and that all stakeholders are involved. Ready-made programs like the 11+ and Knäkontroll are first and foremost developed for younger players. At the senior elite and professional level, the structure of the club is more complex. A recent study from the professional league in Qatar documents how injury prevention practices depend on good communication between the medical and technical teams and how the fitness coach has a crucial facilitator role as the link between stakeholders. The study also showed that a single approach to injury prevention like a warm-up program is unlikely to succeed, especially in a multicultural and multi-disciplinary setting63. This is even the case at the elite junior level; indeed, elite academy teams in Europe do not use ready-made-programs like 11+, but adapt them to their setting and barriers (e.g., time and scheduling, player workload) and also employ a mix from a range of different, internally developed programs64.
For the elite level, we suggest that a different approach is needed: A holistic approach to player preparation with complete buy-in from the players and their support staff represents the best solution teams can implement to reduce the risk of injury and illness and promote consistent high-level performance. To this end, we are now developing a novel, systematic approach to risk management in the Qatar Stars League in collaboration between Aspetar Sports Injury & Illness Prevention Program (ASPREV) and the National Sports Medicine Programme (NSMP).
Roald Bahr M.D., Ph.D
Bahar Hassanmirzaei M.D.
Montassar Tabben Ph.D
Mokhtar Chaabane M.D.
Souhail Chebbi M.D.
Raouf Nader Rekik M.D.
Ramadan Daoud Ph.D.
Yorck Olaf Schumacher M.D.
Karim Chamari Ph.D.
Aspetar Orthopaedic and Sports Medicine Hospital
Doha, Qatar
Contact: roald.bahr@aspetar.com
References
1. Rekik RN, Tabben M, Eirale C, Landreau P, Bouras R, Wilson MG, et al. ACL injury incidence, severity and patterns in professional male soccer players in a Middle Eastern league. BMJ Open Sport Exerc Med. 2018;4(1):e000461.
2. Zech A, Hollander K, Junge A, Steib S, Groll A, Heiner J, et al. Sex differences in injury rates in team-sport athletes: A systematic review and meta-regression analysis. J Sport Health Sci. 2022;11(1):104-14.
3. Pangrazio O, Forriol F. Epidemiology of soccer players traumatic injuries during the 2015 America Cup. Muscles Ligaments Tendons J. 2016;6(1):124-30.
4. Myklebust G, Engebretsen L, Braekken IH, Skjolberg A, Olsen OE, Bahr R. Prevention of anterior cruciate ligament injuries in female team handball players: a prospective intervention study over three seasons. Clin J Sport Med. 2003;13(2):71-8.
5. Olsen OE, Myklebust G, Engebretsen L, Bahr R. Injury mechanisms for anterior cruciate ligament injuries in team handball: a systematic video analysis. Am J Sports Med. 2004;32(4):1002-12.
6. Soligard T, Myklebust G, Steffen K, Holme I, Silvers H, Bizzini M, et al. Comprehensive warm-up programme to prevent injuries in young female footballers: cluster randomised controlled trial. BMJ (Clinical research ed). 2008;337:a2469.
7. Walden M, Atroshi I, Magnusson H, Wagner P, Hagglund M. Prevention of acute knee injuries in adolescent female football players: cluster randomised controlled trial. BMJ. 2012;344:e3042.
8. Rudisill SS, Varady NH, Kucharik MP, Eberlin CT, Martin SD. Evidence-Based Hamstring Injury Prevention and Risk Factor Management: A Systematic Review and Meta-analysis of Randomized Controlled Trials. Am J Sports Med. 2022:3635465221083998.
9. Haroy J, Clarsen B, Wiger EG, Oyen MG, Serner A, Thorborg K, et al. The Adductor Strengthening Programme prevents groin problems among male football players: a cluster-randomised controlled trial. Br J Sports Med. 2019;53(3):150-7.
10. Perez-Gomez J, Adsuar JC, Alcaraz PE, Carlos-Vivas J. Physical exercises for preventing injuries among adult male football players: A systematic review. J Sport Health Sci. 2022;11(1):115-22.
11. Brito J, Mendes R, Figueiredo P, Marques JP, Beckert P, Verhagen E. Is it Time to Consider Quaternary Injury Prevention in Sports? Sports Med. 2022.
12. Della Villa F, Buckthorpe M, Grassi A, Nabiuzzi A, Tosarelli F, Zaffagnini S, et al. Systematic video analysis of ACL injuries in professional male football (soccer): injury mechanisms, situational patterns and biomechanics study on 134 consecutive cases. Br J Sports Med. 2020;54(23):1423-32.
13. Rekik RN, Bahr R, Cruz F, Read P, Whiteley R, D’Hooghe P, et al. Mechanisms of ACL injuries in men’s football: A systematic video analysis over six seasons in the Qatari professional league. Biology of Sport. 2022.
14. Bizzini M, Dvorak J. FIFA 11+: an effective programme to prevent football injuries in various player groups worldwide-a narrative review. Br J Sports Med. 2015;49(9):577-9.
15. Silvers-Granelli H, Mandelbaum B, Adeniji O, Insler S, Bizzini M, Pohlig R, et al. Efficacy of the FIFA 11+ Injury Prevention Program in the Collegiate Male Soccer Player. Am J Sports Med. 2015;43(11):2628-37.
16. Silvers-Granelli HJ, Bizzini M, Arundale A, Mandelbaum BR, Snyder-Mackler L. Does the FIFA 11+ Injury Prevention Program Reduce the Incidence of ACL Injury in Male Soccer Players? Clin Orthop Relat Res. 2017;475(10):2447-55.
17. Al Attar WSA, Faude O, Bizzini M, Alarifi S, Alzahrani H, Almalki RS, et al. The FIFA 11+ Shoulder Injury Prevention Program Was Effective in Reducing Upper Extremity Injuries Among Soccer Goalkeepers: A Randomized Controlled Trial. Am J Sports Med. 2021;49(9):2293-300.
18. Ejnisman B, Barbosa G, Andreoli CV, de Castro Pochini A, Lobo T, Zogaib R, et al. Shoulder injuries in soccer goalkeepers: review and development of a FIFA 11+ shoulder injury prevention program. Open Access J Sports Med. 2016;7:75-80.
19. Fédération Internationale de Football Association, The goalkeeper warm-up programme. [Internet]. 2019. Available from: https://digitalhub.fifa.com/m/5f99d48b566fb97a/original/leaa0liy1z81qzxeg08m-pdf.pdf.
20. Fédération Internationale de Football Association, FIFA 11+ Referees Injury Prevention Program manual. [Internet]. 2018. Available from: https://www.fifamedicalnetwork.com/wp-content/uploads/2016/11/fifa_11_referee_manual.pdf.
21. Rossler R, Donath L, Bizzini M, Faude O. A new injury prevention programme for children's football--FIFA 11+ Kids--can improve motor performance: a cluster-randomised controlled trial. J Sports Sci. 2016;34(6):549-56.
22. Lindblom H, Sonesson S, Torvaldsson K, Waldén M, Hägglund M. Extended Knee Control programme lowers weekly hamstring, knee and ankle injury prevalence compared with an adductor strength programme or self-selected injury prevention exercises in adolescent and adult amateur football players: a two-armed cluster-randomised trial with an additional comparison arm. Br J Sports Med. 2023;57(2):83-90.
23. Knäkontroll. Knee control - SISU Förlag 2020 [
24. Arnason A, Andersen TE, Holme I, Engebretsen L, Bahr R. Prevention of hamstring strains in elite soccer: an intervention study. Scand J Med Sci Sports. 2008;18(1):40-8.
25. Mjølsnes R, Arnason A, Østhagen T, Raastad T, Bahr R. A 10-week randomized trial comparing eccentric vs. concentric hamstring strength training in well-trained soccer players. Scand J Med Sci Sports. 2004;14(5):311-7.
26. van Dyk N, Behan FP, Whiteley R. Including the Nordic hamstring exercise in injury prevention programmes halves the rate of hamstring injuries: a systematic review and meta-analysis of 8459 athletes. Br J Sports Med. 2019;53(21):1362-70.
27. Chebbi S, Chamari K, Van Dyk N, Gabbett T, Tabben M. Hamstring Injury Prevention for Elite Soccer Players: A Real-World Prevention Program Showing the Effect of Players' Compliance on the Outcome. J Strength Cond Res. 2022;36(5):1383-8.
28. Serner A. Diagnosis of acute groin injuries in athletes. Br J Sports Med. 2017;51(23):1709-10.
29. Whittaker JL, Small C, Maffey L, Emery CA. Risk factors for groin injury in sport: an updated systematic review. Br J Sports Med. 2015;49(12):803-9.
30. Ishoi L, Sorensen CN, Kaae NM, Jorgensen LB, Holmich P, Serner A. Large eccentric strength increase using the Copenhagen Adduction exercise in football: A randomized controlled trial. Scand J Med Sci Sports. 2016;26(11):1334-42.
31. Harøy J, Clarsen B, Wiger EG, Oyen MG, Serner A, Thorborg K, et al. The Adductor Strengthening Programme prevents groin problems among male football players: a cluster-randomised controlled trial. Br J Sports Med. 2019;53(3):150-7.
32. Noyes FR, Barber-Westin SD. Neuromuscular retraining intervention programs: do they reduce noncontact anterior cruciate ligament injury rates in adolescent female athletes? Arthroscopy. 2014;30(2):245-55.
33. Stevenson JH, Beattie CS, Schwartz JB, Busconi BD. Assessing the effectiveness of neuromuscular training programs in reducing the incidence of anterior cruciate ligament injuries in female athletes: a systematic review. Am J Sports Med. 2015;43(2):482-90.
34. Sugimoto D, Myer GD, Foss KD, Hewett TE. Specific exercise effects of preventive neuromuscular training intervention on anterior cruciate ligament injury risk reduction in young females: meta-analysis and subgroup analysis. Br J Sports Med. 2015;49(5):282-9.
35. McCall A, Carling C, Nedelec M, Davison M, Le Gall F, Berthoin S, et al. Risk factors, testing and preventative strategies for non-contact injuries in professional football: current perceptions and practices of 44 teams from various premier leagues. Br J Sports Med. 2014;48(18):1352-7.
36. McCall A, Dupont G, Ekstrand J. Injury prevention strategies, coach compliance and player adherence of 33 of the UEFA Elite Club Injury Study teams: a survey of teams' head medical officers. Br J Sports Med. 2016;50(12):725-30.
37. Ross SE, Guskiewicz KM, Gross MT, Yu B. Assessment tools for identifying functional limitations associated with functional ankle instability. J Athl Train. 2008;43(1):44-50.
38. McGuine TA, Greene JJ, Best T, Leverson G. Balance as a predictor of ankle injuries in high school basketball players. Clin J Sport Med. 2000;10(4):239-44.
39. Wang YC, Zhang N. Effects of plyometric training on soccer players. Exp Ther Med. 2016;12(2):550-4.
40. Slimani M, Chamari K, Miarka B, Del Vecchio FB, Cheour F. Effects of Plyometric Training on Physical Fitness in Team Sport Athletes: A Systematic Review. J Hum Kinet. 2016;53:231-47.
41. Jlid MC, Racil G, Coquart J, Paillard T, Bisciotti GN, Chamari K. Multidirectional Plyometric Training: Very Efficient Way to Improve Vertical Jump Performance, Change of Direction Performance and Dynamic Postural Control in Young Soccer Players. Front Physiol. 2019;10:1462.
42. Asadi A, Saez de Villarreal E, Arazi H. The Effects of Plyometric Type Neuromuscular Training on Postural Control Performance of Male Team Basketball Players. J Strength Cond Res. 2015;29(7):1870-5.
43. Al Attar WSA, Bakhsh JM, Khaledi EH, Ghulam H, Sanders RH. Injury prevention programs that include plyometric exercises reduce the incidence of anterior cruciate ligament injury: a systematic review of cluster randomised trials. J Physiother. 2022;68(4):255-61.
44. Behm DG, Blazevich AJ, Kay AD, McHugh M. Acute effects of muscle stretching on physical performance, range of motion, and injury incidence in healthy active individuals: a systematic review. Appl Physiol Nutr Metab. 2016;41(1):1-11.
45. Huang K, Ihm J. Sleep and Injury Risk. Curr Sports Med Rep. 2021;20(6):286-90.
46. Clemente FM, Afonso J, Costa J, Oliveira R, Pino-Ortega J, Rico-Gonzalez M. Relationships between Sleep, Athletic and Match Performance, Training Load, and Injuries: A Systematic Review of Soccer Players. Healthcare (Basel). 2021;9(7).
47. Oliveira CC, Ferreira D, Caetano C, Granja D, Pinto R, Mendes B, et al. Nutrition and Supplementation in Soccer. Sports (Basel). 2017;5(2).
48. Belval LN, Hosokawa Y, Casa DJ, Adams WM, Armstrong LE, Baker LB, et al. Practical Hydration Solutions for Sports. Nutrients. 2019;11(7).
49. Ludwig DS, Kushi LH, Heymsfield SB. Conflicts of Interest in Nutrition Research. JAMA. 2018;320(1):93.
50. Turnagol HH, Kosar SN, Guzel Y, Aktitiz S, Atakan MM. Nutritional Considerations for Injury Prevention and Recovery in Combat Sports. Nutrients. 2021;14(1).
51. Drew MK, Finch CF. The Relationship Between Training Load and Injury, Illness and Soreness: A Systematic and Literature Review. Sports Med. 2016;46(6):861-83.
52. Soligard T, Schwellnus M, Alonso JM, Bahr R, Clarsen B, Dijkstra HP, et al. How much is too much? (Part 1) International Olympic Committee consensus statement on load in sport and risk of injury. Br J Sports Med. 2016;50(17):1030-41.
53. Haddad M, Stylianides G, Djaoui L, Dellal A, Chamari K. Session-RPE Method for Training Load Monitoring: Validity, Ecological Usefulness, and Influencing Factors. Front Neurosci. 2017;11:612.
54. Djaoui L, Haddad M, Chamari K, Dellal A. Monitoring training load and fatigue in soccer players with physiological markers. Physiol Behav. 2017;181:86-94.
55. Verhagen EA, Bay K. Optimising ankle sprain prevention: a critical review and practical appraisal of the literature. Br J Sports Med. 2010;44(15):1082-8.
56. Hennig EM. Plantar pressure measurements for the evaluation of shoe comfort, overuse injuries and performance in soccer. Footwear science. 2014;6(2):119-27.
57. Jastifer J, Kent R, Crandall J, Sherwood C, Lessley D, McCullough KA, et al. The Athletic Shoe in Football. Sports Health. 2017;9(2):126-31.
58. Orchard JW, Walden M, Hagglund M, Orchard JJ, Chivers I, Seward H, et al. Comparison of injury incidences between football teams playing in different climatic regions. Open Access J Sports Med. 2013;4:251-60.
59. Thomson A, Whiteley R, Wilson M, Bleakley C. Six different football shoes, one playing surface and the weather; Assessing variation in shoe-surface traction over one season of elite football. PLoS One. 2019;14(4):e0216364.
60. Vriend I, Valkenberg H, Schoots W, Goudswaard GJ, van der Meulen WJ, Backx FJ. Shinguards effective in preventing lower leg injuries in football: Population-based trend analyses over 25 years. J Sci Med Sport. 2015;18(5):518-22.
61. Fédération Internationale de Football Association, Equipment regulations. [Internet]. 2015. Available from: https://digitalhub.fifa.com/m/4028a792bb93a722/original/q3drmdesvc8bbmanff8d-pdf.pdf.
62. Tatar Y, Ramazanoglu N, Camliguney AF, Saygi EK, Cotuk HB. The effectiveness of shin guards used by football players. J Sports Sci Med. 2014;13(1):120-7.
63. Tabben M VE, Marit W, Chaabane M, Schumacher Y O, Alkhelaifi Kh, Hassanmirzaei B, Bahr R, Chamari K, Bolling C. Obstacles and Opportunities for Injury Prevention in Professional Football in Qatar: Exploring the Implementation Reality. BMJ Open Sport & Exercise Medicine (in press) 2023.
64. O'Brien J, Finch CF. The implementation of musculoskeletal injury-prevention exercise programmes in team ball sports: a systematic review employing the RE-AIM framework. Sports Med. 2014;44(9):1305-18.
Header image by Goran Has (Cropped)