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ORIGINAL RESEARCH
Lower limb injuries in an english professional football club: injury analysis and
recommendations for prevention
Mohamad Y. Fares
a
, Katy Stewart
a,b
, Michael McBride
b
and John Maclean
a,b,c
a
College of Medical, Veterinary, and Life Sciences, University of Glasgow, Glasgow, Scotland, UK;
b
Hampden Sports Clinic, Glasgow, Scotland, UK;
c
Institute of Cardiovascular and Medical Sciences, University of Glasgow, Glasgow, Scotland, UK
ABSTRACT
Background: Lower limb injuries constitute a problem in the sport of football. Our aim is to explore
patterns and trends of lower limb injuries in an English professional football club.
Methods: This is a descriptive epidemiological study. Reports provided by the club’s physical therapy
team were screened for injuries among professional football players sustained over four seasons, from
2015/2016 to 2018/2019. Data included setting of injury (in-match or training), anatomical location of
injury, type of injury, number of days off and month of injury.
Results: A total of 296 lower limb injuries were recorded in our study, with a rate of 11.14 per 1000
football hours. Injury rate during games was 51.38 per 1000 football hours, significantly greater than
that during training at 3.81 per 1000 football hours (p = 0.021). The thigh was significantly the most
commonly injured location at 4.67 per 1000 football hours (p < 0.001). Grade I tears were the most
common injury type at 1.73 per 1000 football hours, significantly greater than grade III tears (p = 0.027),
contusions (p = 0.043), fractures (p = 0.02), and lacerations (p = 0.019). Injury rates were found to be
greatest during preseason and declined as season progressed. On average, an injury sidelined the
affected footballer for a total of 20 days.
Conclusion: Lower limb injuries were more common during matches than training. The thigh is the
most common injury location, and grade I muscle tear was the most common type of injury. Injury rates
were higher early on in the season. Potential prevention strategies include spacing out competition,
adopting training and exercise regimens that cater for recovery, and increasing research regarding
injury mechanisms.
ARTICLE HISTORY
Received 18 October 2021
Accepted 15 February 2022
KEYWORDS
Soccer; injury; leg;
prevention; thigh
Introduction
Football, otherwise known as soccer, is a sport that possesses
a huge base of loyal fans and practitioners and is widely
regarded as the most popular in the world [1]. In fact, the
2007 Federation Internationale de Football Association (FIFA)
report stated that more than 200,000 professional and
265 million amateur players were registered with the associa-
tion worldwide [1].
The high physiological demands of this sport, be it in
training or during matches, raise concern for high rates of
injuries in football- mainly those to the lower limb [2,3]. In
fact, multiple studies addressed the effect of fatigue and strain
in training and matches, and how this relates to football
injuries [4–6]. That is because the player is required to sustain
high aerobic (e.g. running) and anaerobic (e.g. sprinting) loads
for a prolonged period (90 minutes per match), and this
eventually leads to fatigue and exhaustion, and consequently
predisposes to injury. As such, lower limb strain injuries are
prevalent in sports like football, where there is high involve-
ment of movements like running, sprinting, jumping and
pivoting [7]. In addition, being a contact sport in its essence
means that it can predispose to a high number of traumatic
injuries like fractures and contusions. All these injuries can be
debilitating and incapacitating in nature and can impair
performance, motivation, and quality of life. Consequently,
lower limb injuries in football constitute huge athletic and
financial burdens for the affected athletes and their respective
clubs [8].
Research exploring the patterns and trends of these injuries
is essential to better understand their dynamics and repercus-
sions, and to possibly establish prevention plans and strate-
gies [8]. The high probability of injury and the worldwide
popularity of the sport imply detrimental consequences on
practitioner’s health. Few studies in the literature describe
the epidemiology of lower limb injuries in football [9–12]. It
is important to comprehensively explore different variables
associated with the lower limb for the purpose of deducing
possible connections and relationships between the variable
and the injury, and incorporating these relationships into pre-
ventive recommendations and strategies. These variables can
include injury type, location, setting, timing, and resultant
time off due to injury.
While the few studies in the literature do describe the
general injury profile of the sport, none provide a holistic
exploration of the mentioned variables in the lower limb,
and none provide an extensive insight into non-play related
risk factors that can affect injury rates. In that sense, the aim of
our study was to explore the patterns and trends of lower limb
CONTACT Mohamad Y. Fares 2423564F@student.gla.ac.uk College of Medical, Veterinary, and Life Sciences, University of Glasgow, Glasgow, Scotland, UK
THE PHYSICIAN AND SPORTSMEDICINE
https://doi.org/10.1080/00913847.2022.2045176
© 2022 Informa UK Limited, trading as Taylor & Francis Group
injuries in football, by screening a professional English football
club over four seasons, and at both competitive and training
settings, considering the variables mentioned above. We also
aim to conduct a holistic review of current literature on other
alternative risk factors that may affect injury risk, in order to
deduce possible recommendations and prevention strategies.
Methods
Study design
Our study is a descriptive epidemiological study. Our study
analyzed the reports provided by the club’s physical therapy
team, and included injuries sustained both in-match and dur-
ing training. Players and club administration provided consent
for the use of the deidentified data in our project.
Study database
Data pertaining to injured athletes from a professional English
football club were obtained, from season 2015/2016 up till
season 2018/2019 (inclusive). All lower limb injuries sustained
by the team were included in our study. All matches, including
friendlies, league matches and cup matches, were included.
The final dataset obtained included anatomical location of
injury, type of injury, setting (in-match or during training),
number of days off due to injury, month of injury, side of
injury, and whether re-injury occurred.
Participants
Participants included all the first-team footballers of
a professional English football club, participating in both train-
ing and matches. Injured athletes were assessed by the club’s
physical therapists and all relevant information was recorded.
Definitions
Lower limb injuries were defined as any injury occurring to the
lower limb, which resulted in the footballer being sidelined from
play. These were divided into six anatomical locations: hip/groin,
thigh, knee, leg, ankle, and foot, as specified by the treating
physical therapist. Similarly, injury types were classified into
multiple categories which included: muscular or ligamentous
tears, contusions, fractures, lacerations, and others. Tears were
further classified into grades: grade I tears, where mild damage
to muscular or ligamentous fibers occurred; grade II tears, where
much more extensive damage to the fibers took place; and
grade III tears, where total rupture of the fibers is witnessed [13].
Injuries were also categorized according to the duration of
recovery: mild injuries were those that sidelined players for
1 week or less; moderate injuries were those that sidelined
players for a duration between 1 and 4 weeks; severe injuries
were those that sidelined players for more than 4 weeks [11].
Procedure (calculating football hours)
A typical season in English football extends over 38 weeks,
from early August till the start of May, with preseason
friendlies usually taking place during the month of July. Each
week generally consists of 4 training days (where 1-hour-30-
minute training sessions take place), a day off, a professional
game, and a recovery session the day after a match [2]. When
two matches occur within one week, two training sessions
take place instead of four and two recovery sessions are
held, with one day off (Table 1). According to this general
schema (Table 1), we reported the number of training ses-
sions, professional games, and first team players involved in
each season.
Athletic exposures
In order to calculate athletic exposures and incidence rates of
lower limb injuries, we calculated the number of football hours
involved in one event (training sessions or games) and multi-
plied it by the number of footballers participating in these
football hours: training sessions involve the entirety of the first
team; hence, calculating football hours of one training session
was done by multiplying the number of first team players by the
number of hours in one training session (1.5 hours). Match hours
were calculated by multiplying the number of hours involved in
one game (1.5 hours) by the number of players involved in the
match (11 players). Incidence rates during the studied period
were then expressed as injuries per 1000 football hours.
Statistical analysis
We used an independent t-test to check whether any statis-
tical significance occurred between the injury rates during
matches and those during training hours. A one-way analysis
of variance (ANOVA) was used to test for any statistically
significant differences between rates of different lower limb
injury locations and types. In case of significance, an appro-
priate post-hoc test (Tukey vs Games-Howell) was conducted
to indicate which comparisons exhibited a significant result.
We also used Joinpoint Analysis to determine the statistical
significance of the trends of lower limb injury rates across the
different months. P-value less than 0.05 (95% CI (confidence
interval)) was considered statistically significant. Statistical
analyses were performed using Statistical Package for the
Social Sciences for Windows software version 25.0 (IBM SPSS,
2017) and JoinPoint regression analysis software.
Results
Over the studied period, a total of 230 matches and 500 training
sessions took place; during which, 26,577 hours of football expo-
sure took place. These football hours witnessed a total of 339
football injuries, constituting a total injury rate of 12.75 per 1000
football hours. Lower limb injuries constituted 296 injuries (87%)
and an injury rate of 11.14 per 1000 football hours (n = 296).
Football matches witnessed 209 injuries, constituting an injury
rate of 55.1 per 1000 football hours. On the other hand, training
sessions witnessed 87 injuries, with an injury rate of 3.81 per 1000
football hours. Accordingly, training sessions had a significantly
lower injury rate when compared to football matches (p = 0.021; CI
[−83.8,-14]). Injury setting was unspecified in 13 cases (Table 2).
2M. Y. FARES ET AL.
Injuries affected the right lower extremity in 163 cases
(55%), the left lower extremity in 131 cases (44%), and bilateral
lower extremities in 2 cases (1%). An MRI was needed in the
diagnosis of 85 cases (29%). Re-injury occurred in 26 inci-
dents (9%).
Location of injury
The thigh was the most commonly injured location in the
lower limb, with a total of 124 injuries (41.9%) and a rate of
4.67 per 1000 football hours (Figure 1). The knee recorded
a total of 47 injuries (15.9%), and a rate of 1.77 per 1000
football hours. The ankle recorded a total of 40 injuries
(13.5%),and a rate of 1.51 per 1000 football hours. The foot
recorded 33 injuries (11.1%), and a rate of 1.24 per 1000 foot-
ball hours. The leg recorded 30 injuries (10.1%), and a rate of
1.13 per 1000 football hours (Figure 1). And finally, the hip/
groin recorded the lowest number of injuries with 22 injuries
(7.4%), and a rate of 0.83 per 1000 football hours (Figure 1).
Accordingly, the thigh recorded an injury rate that is sig-
nificantly greater than that of the knee- (p < 0.001; CI
[1.55,4.44]), the ankle (p < 0.001; CI[1.73,4.68]), the foot
(p < 0.001; CI[2.1,5]), the leg (p < 0.001; CI[2.13,5.08]), and
the hip/groin (p < 0.001; CI[2.42,5.37]) (Table 3).
Type of injury
The most common type of injury was a grade I tear, with
a frequency of 125 cases (42.2%), and a rate of 4.7 per 1000
football hours. Grade II tears followed with 45 injuries (15.2%)
and an injury rate of 1.69 per 1000 football hours. Contusions
recorded 36 injuries (12.2%) and an injury rate of 1.35 per 1000
football hours. Type of injury was unspecified in 43 cases. The
number, percentage, and rates of different types of injuries
recorded can be seen in Table 4.
When assessing for statistical significance between the
specified types of injuries, the rate of grade I tears was sig-
nificantly higher than grade III tears (p = 0.027; CI[0.86,7.9]),
contusions (p = 0.043; CI[0.16,6.57]), fractures (p = 0.02; CI
[1.14,7.85]), and lacerations (p = 0.019; CI[1.22,7.83]).
Moreover, the rate of grade II tears was significantly higher
than that of fractures (p = 0.042; CI[0.06,2.84]) and lacerations
(p = 0.04; CI[0.08,2.88]) (Table 5).
Table 1. General schema of a monthly schedule for a professional English football club.
Monday Tuesday Wednesday Thursday Friday Saturday Sunday
Day Off Training Training Training Training League Game Recovery
Day Off Training Cup Game Recovery Training League Game Recovery
Day Off Training Training Training Training League Game Recovery
Day Off Training Cup Game Recovery Training League Game Recovery
Table 2. Distribution of total number of games, training sessions, lower limb injuries and lower limb injury rates (per 1000 football hours) across our studied period.
Season
Total Number
of Games
Number of
Training
Sessions
Number of Football
Hours – Games
Number of Football
Hours – Training Sessions
Number of
Injuries – Games
Number of Injuries –
Training Sessions
Injury Rate (per 1000
football hours)
2015/
2016
59 128 973.5 5376 43 23 10.39
2016/
2017
57 132 940.5 7326 62 19 9.80
2017/
2018
63 108 1039.5 4536 41 10 9.15
2018/
2019
51 132 841.5 5544 63 35 15.35
Total 230 500 3795 22,782 209 87 11.14
Figure 1. Percentage of lower limb injury by anatomic location.
THE PHYSICIAN AND SPORTSMEDICINE 3
Timing
The 2018/2019 season witnessed the highest number of
lower limb injuries, with 98 injuries and a rate of 15.35 per
1000 football hours. In contrast, the 2017/2018 season
witnessed the lowest, with 51 injuries and a rate of
9.15 per 1000 football hours (Table 2). Nevertheless, no
significance was found between the injury rates of the
different seasons in our study (p = 0.142). Win rate was
highest in the 2017/2018 season with 65%, followed by the
2015/2016 season with 51. It was much lower during the
2016/2017 and the 2018/2019 seasons, respectively.
When exploring the distribution of injuries according to
months, July was seen to have the highest number of lower
limb injuries with 47 injuries and injury rate of 20.4 per 1000
football hours. That was followed by January with 40 injuries
and injury rate of 14.6 per 1000 football hours. May, on the
other hand, witnessed the lowest number of lower limb inju-
ries with 2 injuries and a rate of 2.5 per 1000 football hours
(Figure 2). When assessing for significant differences between
the injury rates of different months, May had a significantly
lower injury rate when compared to July (p = 0.001; CI[−29.1,-
5.4]) and January (p = 0.043; CI[−23.81, −0.14]).
Upon assessing for any significant trends between the
mean injury rates of different months, Joinpoint regression
tool found no significance, but observed one joinpoint. Mean
injury rates decreased steeply at a slope of −3.59 over months:
July- September, and then at a much steadier slope of −0.38
over the months: October-May (Figure 2).
Days off
On average, a lower limb injury sidelined the affected footballer
for a total of 20 days. Mild injuries were the most common, with
152 injuries (51%) sidelining footballers for less than one week.
Moderate injuries, those that sidelined footballers for a duration
of 1–4 weeks followed with 104 injuries (35%) (Figure 3). Severe
injuries were reported in 40 cases (14%), where the resultant
time off due to injury was greater than four weeks (Figure 3).
The number of moderate injuries was significantly higher than
that of severe injuries (p < 0.001; CI[10,21.5]).
Figure 2. The trend of mean lower limb injury rates over our studied period.
Table 3. Comparison of lower limb injury rates according to anatomical location. (Negative value = Column value < Row value).
Hip Thigh Knee Leg Ankle
MD P value MD P value MD P value MD P value MD P value
Foot −0.37 0.96 3.53 <0.001* 0.55 0.83 −0.08 1 0.32 0.98
Ankle −0.69 0.68 3.21 <0.001* 0.24 1 −0.4 0.95 n/a n/a
Leg −0.3 0.99 3.61 <0.001* 0.63 0.75 n/a n/a 0.4 0.95
Knee −0.93 0.38 2.97 <0.001* n/a n/a −0.63 0.75 −0.24 1
Thigh −3.9 <0.001* n/a n/a −2.97 <0.001* −3.61 <0.001* −3.21 <0.001*
Hip n/a n/a 3.9 <0.001* 0.93 0.38 0.3 0.99 0.69 0.68
MD = Mean Difference.
4M. Y. FARES ET AL.
Mild injuries constituted the greatest proportion of injuries
in all anatomic locations of the lower limb other than the
thigh, where moderate injuries were the most common at
51% (Figure 3). The highest proportion of severe injuries was
noted in the knee, with 28% of knee injuries sidelining foot-
ballers for more than 40 days (Figure 3). The distribution of the
severity of injuries according to other anatomic locations can
be seen in Figure 3.
Discussion
Our aim was to explore the patterns and trends of lower limb
injuries in football. Our findings highlighted that the lower
limb accounted for a high percentage of injuries in the sport. It
also showed that rates are higher during competition than in
training, that the thigh was the most commonly injured ana-
tomical location in the lower limb, and that ‘grade I tear’ was
the most commonly observed injury type. The majority of
injuries were mild in nature, and the highest proportion of
severe injuries was attributed to the knee. Our findings also
showed that injury rates were highest during preseason, and
generally decreased as the season progressed.
Lower limb injuries accounted for the majority of injuries in
our study with a percentage of 87% and a rate of 11.14 per
1000 football hours. Consequently, they entail a prominent
problem in the sport. This falls in accordance with other
studies in the literature which reported lower limb injury
percentages of 85%, 76.8%, and 87% in football [9–11]. The
lower limb is increasingly prone to injury in this sport, due to
its involvement in many of its stress-inducing actions and
activities, like dribbling, sprinting, shooting and tackling the
ball. Additionally, our findings regarding lower limb anatomi-
cal location and injury type fall in accordance with other
studies in the literature, where thigh muscle groups were the
Table 4. Distribution of the number, percentage and rate (per 1000 football hours) of lower limb injuries according to type.
Injury Type Number of Injuries Percentage Injury Rate (per 1000 football hours)
Grade 1 Tear 124 41.9 4.7
Grade 2 Tear 44 14.9 1.69
Grade 3 Tear 10 3.4 0.38
Contusion 36 12.2 1.35
Fracture 8 2.7 0.3
Laceration 6 2.0 0.23
Others 25 8.4 0.87
Unspecified 43 14.5 1.62
Total 296 100.0 11.14
Table 5. Comparison of lower limb injury rates according to type. (Negative value = Column value < Row value).
Grade I Tear Grade II Tear Grade III Tear Contusion Fracture
MD P value MD P value MD P value MD P value MD P value
Laceration 4.52 0.019* 1.48 0.04* 0.14 0.962 1.16 0.07 0.028 1
Fracture 4.45 0.02* 1.45 0.042* 0.11 0.972 1.13 0.071 n/a n/a
Contusion 3.37 0.043* 0.322 0.941 −1.02 0.112 n/a n/a −1.13 0.071
Grade III Tear 4.38 0.027* 1.34 0.075 n/a n/a 1.02 0.112 −0.11 0.972
Grade II Tear 3.02 0.057 n/a n/a −1.34 0.075 −0.322 0.941 −1.45 0.042*
Grade I Tear n/a n/a −3.02 0.057 −4.38 0.027* −3.37 0.043* −4.45 0.02*
Figure 3. Distribution of the severity of recorded lower limb injuries according to anatomic location by percentage (%).
THE PHYSICIAN AND SPORTSMEDICINE 5
most commonly injured, and muscle tears were the most
common injuries [14–16].
When exploring the rate of lower limb injuries in football,
one must provide the distinction between the injury rate of
football matches, and that of training hours. Injury rates were
significantly higher during football matches than in training.
Studies in the literature reported congruent findings
[11,12,17]. Training sessions in football may include cardiore-
spiratory and/or endurance training; however, the main focus
is on drills, techniques and exercises that can be reciprocated
on matchday in a way that is devoid of the stress and pressure
witnessed during the match [18]. These training sessions are
generally not exceedingly demanding or exhausting, in order
to prevent high numbers of injured personnel, especially con-
sidering the congested weekly fixture scheduling in football
leagues [19]. In contrast, football matches require prominently
high physical requirements in setting of intense competition.
The thigh was the most commonly injured anatomic loca-
tion in the lower limb. The majority of physical actions con-
ducted in football (running, jumping, kicking) rely heavily on
the muscles of the thigh. Running, for example, relies heavily
on actions from the quadriceps and the hamstrings (Figure 4)
[20]. Shooting a ball mainly engages the quadriceps, the
glutes and hamstrings (Figure 4) [21]. This high involvement
of the thigh explains why it is the most prone to injury in
football, as well as in other similar sports like baseball, basket-
ball, American football, and rugby [21–24].
Muscle and ligament tears were the most common types of
lower limb injuries recorded in our study. Football players face
prominently strenuous physical demands both during training
and during the matches. As a result, overuse injuries are
understandably inevitable. One study showed that during
a 90-min match, professional players cover a mean distance
of 10,714 (± 991 m), out of which, 2492 (± 625 m) was at high
speed [25]. This overwhelming pace, the highly congested
fixture and training schedule, and the lack of sufficient recov-
ery periods, predispose the players to a high risk of muscle
strain and tears [19]. In addition, the involvement of dribbling,
sprinting and pivoting at high speeds increase the risk of
ligamentous injuries [26]. As a result, it would be reasonable
to find that muscle and ligament tears were the most preva-
lent. Other injury types like fractures, lacerations and contu-
sions were also present in our study, mainly due to the nature
of this contact sport, which often involves traumatic collisions
between players, like tackles and bumps [27].
Our study did not show significant differences between the
four seasons 2015–2019. In addition, no relationship existed
between win rate and lower limb injury rate, and this may be
due to the fact that the club competed in different leagues
during the studied period. The month with the greatest mean
injury rate was July. Our trend analysis showed that injury
rates decreased steeply until the end of September, and
then at a slower slope for the rest of the season, to reach
the lowest rate at the end of the season in May. Multiple
factors can explain these findings. The preseason is a period
that follows a break from football for around 2 months, where
clubs return to prepare for their subsequent season [28]. It
usually occurs in July and involves a congested schedule of
friendlies and training sessions [28,29]. A review in 2016
explored the physiological effects solicited by the off-season
on footballers and warned that deleterious consequences can
arise following a period of more than four weeks with little to
no training: disruptions in players’ body compositions, loss in
neuromuscular performance, and a decrease in aerobic capa-
city [30]. The rapid increase in training loads, strenuous return
to competition, and the inadequate physical maintenance
during vacation are all possible factors as to why July was
the month with the highest injury rate [28]. Hence, adopting
maintenance programs during off-season can help maintain
Figure 4. Muscles used during the actions of running and shooting in football.
6M. Y. FARES ET AL.
fitness levels and decrease overuse injuries early in the season
[30]. As months pass, players would acclimate better to the
training regimens and would cope much more properly with
the stress of competition. In addition, there would be higher
chances of getting knocked out of concurrently ongoing com-
petitions (like the FA Cup or the League Cup), and this would
decrease the congestion of fixtures for the remainder of the
season. This could explain why the injury rate progressively
decreased along the remainder of the season. This trend
(described in our study) was also evident in other sports like
baseball and basketball [24,31].
The variation in the lower limb injuries recorded in our
study, entailed a subsequent variation in severity and extent.
Grade I tears were the most common type of injuries, and
that translated into mild injuries taking up more than half
the number of injuries suffered. Moderate injuries were
the second most common injuries with respect to extent,
and only a small portion of the injuries were severe and
required more than one month off play. As discussed above,
the thigh is involved in many of the actions in football, and
the high risk of overuse and strain injuries would then explain
why moderate and mild injuries were the highest in this
anatomic location [20]. On the other hand, the knee is
a complex joint that relies on surrounding ligaments and
structures for stability and function. The ligaments surround-
ing the knee are sensitive and vulnerable, especially in the
setting of football competitions [28,32]. Sprinting, braking,
pivoting, and jumping motions predispose this joint to high
chances of ligamentous injuries, many of which require inva-
sive treatment procedures and lengthy recovery periods
[27,33]. One study conducted a systematic video analysis of
ACL injuries in Italian football and noted four major situational
patterns for injury: pressing and tackling, getting tackled,
rebalancing following kicking, and landing from a jump [34].
Given the abundance of these situational patterns in the sport,
one can understand why the highest proportion of severe
injuries was found in the knee joint.
On average, and according to our study, a lower limb injury
in football sidelined the player for around 20 days. Professional
English footballers under contract are paid regardless of their
participation in matches or training sessions; and according to
their reported salaries, the average lower limb injury would cost
around 150,000 British pound sterling (GBP) – equivalent to
around 203,000 United States Dollar (USD)- in time loss for
a club in the English Premier League, and around 30,000 GBP
(around 41,000 USD) for a club in the Championship – that is
excluding treatment fees [35,36]. This finding highlights the
prominent economic impact of lower limb injuries on the
clubs, and the importance of conducting preventive research
in this domain [37].
In light of the findings of this study, several play-related
risk factors can be tackled in order to help attenuate the
spread of lower limb injuries in football. Spacing out compe-
tition and incorporating more weekly recovery sessions, espe-
cially early on during the season, would allow for a gradual
increase in training loads and would reduce the risk of over-
use strain injuries. Lengthening the preseason and
encouraging maintenance of fitness levels during off-season
can also help decrease lower limb injury rates. Encouraging
player rotation, by increasing the number of substitutions
and distributing on-field playing time adequately among
players would further decrease in-match exposure and
reduce injury risk. Implementing light training programs dur-
ing off-season would help maintain fitness levels in athletes
and reduce injuries early on in the season. Ensuring the use
of shin pads during training may decrease the frequency of
traumatic injuries like fractures and contusions.
In addition, continuously researching and applying addi-
tional evidence-based interventions that can help reduce
injury risk and improve performance is pivotal for developing
effective strategies. For example, a recent study explored the
effect of the hardness of cleat outsoles on lower limb kine-
matics and kinetics [38]. The study found that adopting
softer material in the heel region of the shoe, and material
of medium hardness in the medial forefoot, can help prevent
injury and improve performance [38]. Adopting training regi-
mens that focus on healing, stretching and strengthening
vulnerable areas of the lower limb is essential to help accli-
mate and condition the muscles for longer periods of stress
[39,40]. According to our findings, these would be exercises
that help prevent injuries in the muscle groups of the thigh,
as it is the most common site for injury in the sport. Research
regarding eccentric training exercises have shown promise
for hamstring injury prevention, with injury reduction rates
reaching 65–70% [41,42]. One specific regimen that specia-
lizes in eccentric hamstring exercises is the Nordic hamstring
(NH) exercise program [43]. While the NH program has
proved to prominently help reduce hamstring injuries in
football, only few clubs incorporated it into its training regi-
men [43,44].
Aside from direct football-related factors, several other
parameters should be further incorporated in preventive
guidelines, and these include sleep, mental health, and
nutrition. Sleep is essential for optimal function and health,
and sleep problems can be associated with risk for injury
[45,46]. Studies targeting football injuries showed that foot-
ballers with shorter sleep times, and lower sleep quality
displayed higher rates of severe musculoskeletal injuries
[46–48]. It was also found that sleep quality is associated
with injury occurrence in elite footballers, thus highlighting
the role of sleep in recovery and performance [49]. Mental
health has also been implicated in football injuries [50]. One
study that explored mental health symptoms in Australian
football, found that mental health symptoms were prevalent
among footballers, and that injury constituted a prominent
risk factor for troubled psychological outcomes among
players [50]. And finally, nutrition has been studied as
a possible factor in football injuries. Studies targeting var-
ious dietary patterns have found that nutritional habits do
play a role in well-being, performance, and recovery [51,52].
For example, a study explored intermittent fasting in foot-
ballers during the month of Ramadan, and found a deficit in
performance of said players [52]. Hence, it is important to
take a holistic approach when devising preventive strategies
THE PHYSICIAN AND SPORTSMEDICINE 7
and plans, and these should include alternative non-play risk
factors.
It is also necessary to address injury prevention from an
administrative perspective, which goes beyond player-
associated risk factors, and includes communication and
leadership strategies developed by coach and staff [53].
During a meeting in Porto in 2013, chief medical officers
were asked about the most common factors contributing to
injuries, and those included the quality of internal commu-
nication, leadership style of head coach, and workload exe-
cuted on players, and their wellbeing [53–55]. A study by
Ekstrand et al in 2018 deliberated more on the subject, as it
showed that higher levels of transformational leadership was
associated with a smaller number of severe injuries [56]. It
also showed that good and positive communication
between training staff and players resulted in lower rates
of injuries and higher attendance rates at training sessions
[56]. This shows that risk factors that stem from staff and
communication need to be integrated into injury prevention
guidelines and strategies.
This study is unique in that it provides a recent and exten-
sive exploration into lower limb injuries in an English football
club and is one of the few to do so in both in-match and in-
training settings, and over multiple seasons. Nevertheless,
several limitations exist. Our study was limited by its retro-
spective nature, and ultimately by the variables used in the
database. In addition, our study did not account for any addi-
tional breaks or days off that may have arisen during the
seasons, and instead, relied on the general scheduling schema
that is based on the matches played (as described in the
Methods section). Finally, when calculating incidence rates of
training sessions, full attendance was assumed, which may
have underestimated the true incidence rates.
Conclusion
Lower limb injuries constitute a prominent medical and
financial problem in football, and the need for additional
research regarding its prevention is warranted. Our study
showed that the thigh is the anatomical location mostly
prone to injury. It also showed that grade I tears was the
most commonly witnessed injury type. The knee was the
anatomical location with the highest proportion of severe
injuries. The preseason witnessed the highest rate of inju-
ries, and time loss differed according to injury extent with
the majority of injuries being mild in severity.
Injury prevention policies and regimens must be enter-
tained in order to decrease lower limb injury rates in football.
These could include spacing out competitions- especially dur-
ing the earlier stages of the season, encouraging player rota-
tion, adopting training regimens that focus on strengthening
and conditioning, incorporating exercise regimens that help
prevent injury in vulnerable muscle groups, and ensuring the
use of protective padding. Applying evidence-based interven-
tions that tackle the biomechanical properties of lower limb
injuries can be prominently helpful, as well, in establishing
proper preventive strategies. Assessing other biochemical fac-
tors like sleep, nutrition and mental health is pivotal for
optimal recovery and performance. And finally, improving
communication between training staff and players has been
shown to reduce injury risk and improve performance.
Disclosure statement
No potential conflict of interest was reported by the author(s).
Funding
This research did not receive any specific grant from funding agencies in
the public, commercial, or not-for-profit sectors.
ORCID
Mohamad Y. Fares http://orcid.org/0000-0001-8228-3953
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THE PHYSICIAN AND SPORTSMEDICINE 9
