Effectiveness of FIFA injury prevention programs in reducing ankle injuries among football players: a systematic review

Search strategy

Five databases were used to ensure all the related articles were included in this systematic review, as well as to ensure and test the reliability and quality of the included studies. We limited our search to studies published from 2008 to 2024 to capture research conducted after the introduction of the FIFA 11+ program, ensuring relevance to current injury prevention strategies. Although only randomized controlled trials (RCTs) were included to maintain methodological rigor, we acknowledge that excluding cohort studies-commonly used in sports injury research-may limit the scope of this review. Future reviews may benefit from incorporating high-quality cohort studies to broaden the evidence base for injury prevention (Soligard et al., 2008). However, the traditional way of searching, namely, a manual search, was also used. The databases searched were MEDLINE (Ovid), PubMed, CINAHL, Scopus and Cochrane Central Register of Controlled Trails (Cochrane library).

The following keywords were used to carry out the electronic searches: “injury prevention” or “FIFA 11+” or “FIFA 11” or “The 11+” or “FIFA 11+ warm-up program” or “neuromuscular training” and “football” or “soccer” and “sport injuries”. The search was conducted by the author from February 2024 to July 2024. Initially, identified articles from the search strategy were uploaded and duplicates were removed, using EndNote. The injury incidence rate or number of injuries to the ankle joint per 1,000 h of football exposure were taken as the outcome measures for this study.

Criteria for selecting studies included only RCTs (level I evidence) to avoid bias and to produce a high quality, systematic review (Evans, 2003). Furthermore, studies that included ankle injury incidence rates or numbers in their outcome measures were eligible for inclusion. Studies that used either the FIFA 11 or the FIFA 11+ injury prevention programs as interventions (see Table 1) were also included in the study.

Study selection

The study selection process aimed to include all the relevant trials in the systematic review (Tacconelli, 2010). The study selection was completed two researchers independently reviewing the eligibility of the trials and to ensuring their reliability, thereby reducing bias (Tacconelli, 2010). The returned studies were screened using the inclusion criteria from the database searches based on the title and the abstract. However, in the case of studies where a decision could not be taken, a full text was obtained to facilitate the decision for their inclusion. After completing the initial screening of the returned articles, complete articles were collected from those that met the inclusion criteria that had been determined by a comprehensive assessment of such criteria. Endnote was utilized for handling references and making decisions on exclusion factors.

Data extraction

The data extracted from that was used in this systematic review; it was adapted from the study by Thorborg et al. (2017). To prevent bias, Mohammad Alhazmi collected the data while Mohammed Zalah independently tested the consistency of, and the information provided by the data extraction process (Tacconelli, 2010). If any discrepancies arose between the evaluators, they were resolved through consensus and arbitration according to a predefined strategy, with Fuzail Ahmad acting as the referee to resolve any disagreements (Tacconelli, 2010). Data were extracted from the five eligible studies that met the inclusion criteria which encompassed study design, participant characteristics, intervention compliance, intervention types, and outcome measures, specifically ankle joint injury incidence. Missing data were sought by contacting study authors via email.

Quality assessment

As this systematic review includes only randomized controlled trials, the PEDro scale was used to assess the quality of the studies involved in this systematic review. The PEDro scale, based on the Delphi list and renewed by Verhagen et al. (1998), is a quality evaluation framework for randomized clinical trials to report systematic reviews (Mokkink et al., 2010). It focuses on covert allocation, intention-to-treat analysis, and follow-up adequacy, making it an effective tool for assessing the quality of physiotherapy and rehabilitation studies (Olivo et al., 2008). The PEDro scale consists of 11 items, but one component (eligibility criteria) pertains to external validity and is not commonly used to measure the method score, resulting in a score range of 0 to 1 (Maher et al., 2003). The PEDro scale was used to assess study quality, with scores ranging from 5 to 7 among the included studies. Lower scores were primarily due to methodological limitations such as lack of blinding (both participants and trainers) and inadequate follow-up periods. Given the nature of exercise intervention studies, blinding was challenging, as trainers were aware of the intervention being implemented, which may introduce performance bias. Inadequate follow-up periods in some studies could also limit the robustness of long-term outcomes. The assessment of the quality of the included studies should is performed by two independent reviewers to avoid bias (Tacconelli, 2010).

Data synthesis

For this project, a systematic review with a narrative synthesis was chosen instead of a meta-analysis due to the high heterogeneity among the included studies. To assess the potential for meta-analysis, we calculated the I² statistic, which indicated substantial variability (>75%) among studies. This variability arose from significant differences in participant demographics and intervention protocols. Participants varied across studies, including adolescent females, adolescent males, and adult males, reflecting differences in biological maturity that could impact ankle injury incidence. Additionally, heterogeneity was evident in the types of FIFA injury prevention programs used, with two studies employing the original FIFA 11 program and three utilizing the modified FIFA 11+ program. These versions differ in warm-up duration, exercises included, and progression, further contributing to study variability. Given these factors, pooling effect sizes in a meta-analysis could produce biased estimates and limit result interpretability. Consequently, a narrative synthesis was selected to provide a more nuanced interpretation of findings across these diverse study contexts.

Injury definitions, injury rates, and the injury rate ratio

In football, an injury is defined as one that prevents players from participating in the next game and training sessions (Al Attar et al., 2016). The injury rate (IR), a key measure in sports research, is calculated by dividing the number of injuries by the total exposure hours (training and games) and multiplying by 1,000 (Caine, Maffulli & Caine, 2008) was used to compare ankle injury incidence between intervention and control groups. The injury rate ratio (IRR), calculated by dividing the IR of the intervention group by the IR of the control group, indicates intervention effectiveness; an IRR less than 1 shows a positive effect (Al Attar et al., 2016). This review used the IRR to demonstrate the effectiveness of the FIFA 11 and FIFA 11+ injury prevention programs in reducing ankle injuries. The total hours of football exposure were also used in this systematic review to compare the findings from the intervention group versus those from the control group. The difference in compliance with the FIFA prevention programs (FIFA 11 and FIFA 11+), which was measured by calculating the number of weekly training sessions for each team and player (Thorborg et al., 2017) between the various studies in this systematic review was used to document the relationship between compliance to the prevention programs and the actual ankle injury reduction rate.

Identified studies

The five electronic databases (MEDLINE (Ovid), PubMed, CINAHL, Scopus, and Cochrane Central Register of Controlled Trials) yielded 640 articles. After the removal of duplicates (150 articles), the remaining 490 articles were excluded after screening titles (420) and abstracts (50). As a result of this culling, 20 articles were obtained for full-text review. Of those, 15 out of the 20 were excluded because they failed to meet the inclusion criteria; for example, they were studies that were conducted on other sports (not football), studies that did not include the FIFA 11 or FIFA 11+ prevention programs in the intervention group, and studies that were not RCTs. A full description of the whole studies identification process is provided in Fig. 1.

Descriptive analysis of the identified studies

A summary of all the studies that were included in this systematic review is available in Table 1. There was a total of five studies, all of which were RCTs. These studies were conducted in four different countries. Two of them were in Norway (Funk, 2011; Evans, 2003), one in the Netherlands (Van Beijsterveldt et al., 2012), one in the USA (Silvers-Granelli et al., 2015) and one in Nigeria (Owoeye et al., 2014).

Sample characteristics

The five included RCTs randomly allocated 158 teams (3,238 players) to the intervention group (the FIF 11 and FIFA 11+ injury prevention programs) and 148 teams (3,071 players) to the control group (the usual training for the team). The mean age of the players in the included studies ranged from 13 to 40 years old. The five included RCTs in three studies which had male footballers (Alhammad et al., 2024; Soligard et al., 2008; Tacconelli, 2010) and in two studies that had female footballers (Funk, 2011; Evans, 2003). Furthermore, none of the included studies had professional football players as a sample; they were either sub-elite or recreational football players (see Table 1).

Types of intervention

Three of the included studies used the FIFA 11+ injury prevention program in the intervention group and two of them used the FIFA 11 prevention program in the intervention group (FIFA 11 is the old version of the FIFA 11+ program; they have minor differences in the components of the exercises, such as the progression levels of the exercises, which can be found only in the FIFA 11+ program) (Thorborg et al., 2017). While all the five studies used the normal or usual training for the teams in the control group to compare it with FIFA 11 and FIFA 11+ programs. none of the included studies exactly explained the components of the usual training for their teams. The intervention duration of the included studies ranged from 5 to 9 months. The frequency of the warm-up or training programs in both the intervention and control groups ranged from 1 to 3 times a week (see Table 1).

All the included studies in this systematic review had a good-to-excellent methodological quality, according to the PEDdro scale, ranging from 5 to 7. The scores for each study depended on the study’s methodology (see Table 2). The PEDro scale measures the study by giving one point (Yes) for each element that has been covered appropriately by the study. Then the total number of points out of 10 is calculated.

There was a big difference in the ankle injury rates per 1,000 h of exposure and in the total ankle injuries number in the five studies included in this systematic review. Table 3 shows the number of ankle injuries, the ankle injury rates per 1,000 of exposure and the total exposure hours for each study.

Exposure hours in the intervention groups and in the control groups

Of the football players in the intervention teams, 158 had exposure to a total of 241,755 h (the FIFA 11+ 153,755 h and FIFA11 87,985 h), while those in the control teams had exposure to a total of 261,016 h. The difference between the intervention group and the control group in terms of the total hours of football exposure (trainings and matches) could have affected the overall results of this systematic review. This possibility was discussed in the discussion chapter. Table 3 provides a summary of the total exposure hours of each included study in this systematic review.

The effect of the FIFA injury prevention programs (FIFA 11 and FIFA 11+) on ankle injury reduction

The five included studies that used the FIFA 11+ and FIFA 11 injury prevention programs in the intervention group included (Funk, 2011; Alhammad et al., 2024; Evans, 2003; Soligard et al., 2008; Tacconelli, 2010). The results demonstrated an 14% ankle injury reduction per 1,000 h of exposure in the intervention group, compared to the control group. The ankle injury rate in the intervention groups was 1.0 per 1,000 h of exposure and 1.16 per 1,000 h of exposure for the control groups. Players in the FIFA 11 and FIFA 11+ groups had 244 ankle injuries in 241,740 h, compared to those in the control group who had 304 ankle injuries in 261,016 h (see Table 4).

The effect of the FIFA 11+ program on ankle injury reduction

Interestingly, the studies that used the FIFA 11+ program in the intervention group (Evans, 2003; Soligard et al., 2008; Tacconelli, 2010) showed a significant reduction in ankle injures incidence of 32% compared to the control group. The ankle injury rates in the FIFA 11+ groups were 0.78 per 1,000 h of exposure compared to the control groups which were 1.14. Football players in the FIFA 11+ group had 120 ankle injuries in 153,755 h compared to those who were playing in the control groups who had 197 ankle injuries in 172,611 h (see Table 4).

The effect of the FIFA 11 program on ankle injury reduction

In contrast, the results pooled from the studies that used the FIFA 11 program in the intervention group (Funk, 2011; Alhammad et al., 2024) indicated that FIFA 11 (old version) was not effective in reducing ankle injuries in football players. The ankle injury rate in the FIFA 11 group was a higher 1.4 per 1,000 h of exposure compared to the control groups which were only 1.12. Furthermore, footballers in the FIFA 11 group had more ankle injuries (124) in a total of 87,985 h compared to the control groups which were 107 in 88,405 h (see Table 4).

The effect of the FIFA 11 and FIFA 11+ programs on ankle sprain injuries

This systematic review also aimed to scope types of ankle injuries, such as ankle sprain, that have been associated with having a preventive effect on the FIFA 11 and FIFA 11+ programs. However, the four included studies did not report the types of ankle injuries, and they reported only the total of ankle injuries which could have been fractures or ankle sprains etc. An exception was the study by Steffen et al. (2008) (FIFA 11), which reported that ankle sprain was the most prevalent (28%) acute injury in both groups (intervention and control group) of the overall acute injuries (421 in total). This study also found that ankle sprain was the most frequent re-injury, with no major difference between both groups (the intervention group had 23 re-injuries and the control group 22 re-injuries). Therefore, these findings indicate that FIFA 11 was not effective in reducing ankle sprain. However, according to the available data in the included studies that used the FIFA 11+ program as an intervention, it is still not clear if FIFA 11+ was effective in reducing ankle sprain.

Compliance with injury prevention programs (FIFA 11+ and FIFA 11)

The number of training sessions that were performed by teams in both the intervention and the control groups ranged from one to three times a week (see Table 1 above). Compliance with the FIFA prevention programs in the included studies ranged from 46% to 77%. For the control group, however, no data, such as the number of weekly training sessions, was provided about their compliance with the usual training.

The findings from the present systematic review indicate that the FIFA 11+ is indeed an effective injury prevention program for ankle injuries in football players. However, the FIFA 11 program (the old version) was not as effective in reducing ankle injuries in football players as the new 11+ program.

Exposure hours and ankle injury incidence rate

The literature indicates a significant relationship between exposure hours and athletes’ injuries, with increased training and match time leading to greater vulnerability to injury risk factors like tiredness and overload (Fong et al., 2009; Stojanovic & Ostojic, 2011). Due to the 19,276-h difference, the risk of injury may have been reduced by teams utilizing FIFA 11 and FIFA 11+, since they had fewer exposure hours (241,740) compared to the control group (261,016). In order to reduce the increased risk of injury, elite players, who often play more matches, must carefully control their exposure hours (Soligard et al., 2008).

Delivery of the FIFA injury prevention programs

The ways in which football players are taught workouts are crucial to the success of the FIFA injury prevention programs. According to research (Sadigursky et al., 2017; Tacconelli, 2010), individuals benefit more from receiving direct supervision from trained professionals like physiotherapists or strength coaches rather than from relying on instructional websites or videos. In comparison to self-teaching techniques, educational workshops with practical demonstrations and constant supervision lead to greater compliance and considerably lower injury rates (Steffen et al., 2008). Steffen et al. (2008), for instance, discovered that injury rates were lower, and compliance was higher in comprehensive teams that had both educational workshops and regular physiotherapist supervision (85.6% vs. 81.3% in the control group and 73.5% in the workshop group). A standardized protocol with comprehensive training and frequent follow-up would improve the program’s preventative benefits, as the program’s efficacy can be affected by a lack of standardization and monitoring in delivery techniques (Evans, 2003; Soligard et al., 2008).

Compliance with the FIFA injury prevention programs

According to Silvers-Granelli et al. (2015) and Steffen et al. (2008), football injury rates are inversely related to compliance with the FIFA 11+ program. Teams with high compliance rates had the lowest incidence of lower limb injuries. The prevalence of ankle injuries was not, however, associated with high compliance with the FIFA 11+ or FIFA 11 programs, according to pooled data. Owoeye et al. (2014) observed a lower ankle injury rate (0.19 per 1,000 h) and a greater compliance rate (77%) with one training session per week, in contrast to Soligard et al. (2008), who reported a higher ankle injury rate (1.0 per 1,000 h) with three sessions per week. Also, despite varying degrees of compliance (53 and 73 percent, respectively), neither Steffen et al. (2008) nor Van Beijsterveldt et al. (2012) found a statistically significant drop in the incidence of ankle injuries. According to Thorborg et al. (2017), further high-quality research is required to determine the exact nature of the connection between the frequency of training sessions, adherence to FIFA injury prevention programs, and the incidence of football injuries, specifically ankle injuries.

Intervention durations of the FIFA injury prevention programs

The length of the interventions in the studies that were included ranged from six to nine months. In order to protect, strengthen, and stabilize skeletal joints, injury prevention exercises rely on long-term factors such as muscle strength (Sadigursky et al., 2017). It is possible that the included studies did not have enough time to develop muscle strength due to the shorter intervention periods. Age, gender, body mass index (BMI), playing level, injury history, data reporting, trainer blinding, control group exercises, screening tests, and player psychology might have impacted this systematic review. The average age of the participants ranged from thirteen to twenty-five, with the exception of one study (Van Beijsterveldt et al., 2012) that included older players and injuries are more common among older players. Because the likelihood of damage varied across sexes, gender played a role in the final results (Doherty et al., 2014). Risk of injury rises as body mass index (BMI) rises (Alahmad et al., 2024). The likelihood of injury is higher for recreational players compared to professionals (Evans, 2003; Caine, Maffulli & Caine, 2008). Recurrence is more likely in cases where injuries have occurred before (Hale & Hertel, 2005) and inaccuracies in reporting data might affect reliability (Sadigursky et al., 2017). Results were skewed since it was difficult to blind the trainers (Willems et al., 2005). There was a lack of direct comparison since the control group did not follow the same workout routine (Owoeye et al., 2014). Injury prevention and early detection might be possible using non-standard screening techniques (Gabbe et al., 2004). Lastly, the psychological state of players, though not addressed in the included studies, can significantly impact injury rates (Ivarsson & Johnson, 2010; Ivarsson, Johnson & Podlog, 2013).

The systematic review identified multiple clinical and contextual factors influencing injury outcomes. Age was a significant factor, as studies showed that older players are more prone to joint degeneration, impacting injury risk (Soligard et al., 2008). Specifically, Van Beijsterveldt et al. (2012) included players aged up to 40, which may have skewed results, as older players are more injury prone (Van Beijsterveldt et al., 2012). Gender also influenced findings, with studies indicating that male players face a higher general injury risk, while female players are more vulnerable to specific injuries like ankle sprains due to hormonal factors (Alahmad et al., 2024). Differences in BMI were noted, as higher BMI correlates with increased ankle injury risk due to joint wear (Gribble et al., 2016), though only two studies included BMI data (Steffen et al., 2008; Tacconelli, 2010). Playing level further impacted results, with amateur players, having lower skill levels, were more susceptible to injury than professionals (Evans, 2003; Caine, Maffulli & Caine, 2008).

A history of previous injuries was another risk factor, as players with prior injuries are at an 80% higher risk for recurrence (Hale & Hertel, 2005). Only one study excluded participants with recent injuries (Owoeye et al., 2014), potentially improving the reliability of its findings. Data reporting methods varied across studies, with inconsistencies in injury and exposure data collection leading to possible inaccuracies; for instance, Soligard et al. (2008) relied on volunteer reporting, which affected data accuracy. Trainer blinding was challenging, as the nature of exercise programs prevents placebo conditions (Van Dyk, Behan & Whiteley, 2019), and lack of blinding in all studies could introduce bias (Willems et al., 2005).

Control group exercise routines were often unspecified, with most control groups following “usual training” without details on components, making direct comparisons difficult (Owoeye et al., 2014). The inclusion of screening tests could further strengthen studies, as tests like the single-leg balance test can identify players at high risk of injury before the season starts (Willems et al., 2005). Lastly, the psychological state of players, such as anxiety or daily stress, is associated with injury risks in both male and female players (Trojian & McKeag, 2006). Monitoring mental health could improve injury prevention efforts.

The FIFA 11+ program demonstrated greater success in reducing ankle injury rates compared to its predecessor FIFA 11, likely due to its emphasis on neuromuscular control and progressive exercises. Variability in player attributes, such as age, gender, BMI, and playing level, alongside contextual factors like compliance rates, exposure hours, and intervention durations, significantly impacted outcomes. High compliance and direct supervision were associated with better results, though inconsistencies in control group routines and data reporting limited direct comparisons. Despite these challenges, the FIFA 11+ program showed promise in reducing ankle injuries.