21
Journal of Exercise Physiologyonline
October 2014
Volume 17 Number 5
Editor-in-Chief
Official Research
Tommy
Journal
Boone,
of the
PhD,
American
MBA
ReviewSociety
Board of Exercise
Todd Astorino,
Physiologists
PhD
Julien Baker, PhD
Steve Brock,
ISSNPhD
1097-9751
Lance Dalleck, PhD
Eric Goulet, PhD
Robert Gotshall, PhD
Alexander Hutchison, PhD
M. Knight-Maloney, PhD
Len Kravitz, PhD
James Laskin, PhD
Yit Aun Lim, PhD
Lonnie Lowery, PhD
Derek Marks, PhD
Cristine Mermier, PhD
Robert Robergs, PhD
Chantal Vella, PhD
Dale Wagner, PhD
Frank Wyatt, PhD
Ben Zhou, PhD
Official Research Journal of
the American Society of
Exercise Physiologists
ISSN 1097-9751
JEPonline
Injuries in Soccer (Football) Referees of Santa Catarina
State
Alberto Inácio da Silva1, Mauro Ricetti Paes2, Mario Cesar de
Oliveira3
Estadual de Ponta Grossa (UEPG) – Ponta Grossa –
PR, Brasil, 2Universidade Federal do Paraná (UFPR) – Curitiba –
PR, Brasil, 3Faculdades Metropolitanas Unidas (FMU) – São Paulo –
SP, Brasil
1Universidade
ABSTRACT
Da Silva AI, Paes MR, Oliveira MC. Injuries in Soccer (Football)
Referees of Santa Catarina State. JEPonline 2014;17(5):21-30.
Sports injuries among athletes are highlighted in studies about
soccer. By comparison, it has long been thought that football
referees are equally susceptible to the same injuries as the football
players. Thus, the purpose of this study was to analyze the situations
where professional soccer referees suffer injuries. The sample
consisted of 101 male referees from the Santa Catarina Soccer
Federation. Three situations were evaluated as to an increase in the
referees’ susceptibility to an injury, and whether the injury would be
considered a sports injury. The situations included during a physical
evaluation, a training session, and a match. Thirty-six referees
(35.6%) reported that they had suffered 54 injuries during their
career. Fifty-four injuries were identified. The referees reported 10
sprains, 19 strains, and 2 fractures. The assistant referees reported
5 sprains, 15 strains, 1 fracture, 1 dislocation, and 1 contusion.
Thirty-nine percent (21) of the injuries occurred during the referees’
training session. The findings indicate that while football referees
suffer few injuries during the game, they do in fact suffer injuries
during the training session or during physical tests. Therefore, the
associations should be more responsible for the development of
preventive training programs in the referee’s routine preparation for
refereeing
Key word: Referees, Soccer, Injuries, Training
22
INTRODUCTION
According to the International Federation of Association Football (FIFA), there are approximately
270 million people directly involved with soccer of which 840,000 are referees and assistant
referees. Ninety-four percent are men and 6% are women. Interestingly, since 2000, the number of
referees has increased by 17% (5). In Brazil, there are more than 25 agencies representing the
soccer referees and, depending on the state, there are at least two entities.
The soccer referee can be considered the 23rd player (6). Fortunately, for safety and ethical play in
soccer, the scientific community has increased its study of referees. However, the number of
scientific studies on football referees is still very small, especially when compared to the volume of
studies with soccer players (11). The anthropometric profiles, movement patterns, physiological
demands during startup, and physical tests of referees and assistant referees have been evaluated
in numerous studies (11). However, there are few studies on the prevention of injuries in soccer,
due to lack of solid evidence about the risk factors and injury mechanisms at different levels of
refereeing (1).
Several studies have reported the incidence of injuries in soccer referees. The authors’ of these
studies evaluated Suisse referees (3,4), FIFA international referees (5), and Brazilian soccer
referees (25). Bizzini et al. in 2009 and 2011 (3,4) and Bizzini and colleagues (5) determined the
injury incidence while refereeing during the game or during the physical training sessions. The
Brazilian study by Paes et al. (25) expanded the investigative field. They sought to identify the
injuries that occurred beyond the playing field and during the training sessions as well as the injuries
that affected the referees during the physical tests imposed by the sports entities to which referees
were affiliated.
The battery of physical tests developed by FIFA to evaluate the soccer referees is controversial. It is
also a very contentious issue that was the focus of studies by Castagna et al. (8), Cerqueira et al.
(9), and Weston et al. (30). However, we are aware of only one study that identified the incidence
and the type of injuries referees are exposed to during the physical tests applied by the federations
and confederations. In addition, many of the studies with referees in Brazil were carried out in the
Paraná state. There is little to nothing is known about the incidence of injury and/or type of injuries
that referees from other states are exposed to. Therefore, the purpose of this study was to analyze
the frequency, circumstances, and characteristics of injuries sustained by soccer referees of the
state of Santa Catarina Soccer Federation (FCF) during the game, training, and/or physical test.
METHODS
Subjects
The procedures used in this retrospective study are consistent with Resolution 196/96 of the
National Health Committee. Also, the procedures were approved by the Research Ethics UEPG
(Resolution 49/2007). The study population consisted of referees and assistant referees accredited
by the Santa Catarina Soccer Federation (FCF).
The sample consisted of 101 male soccer referees. Forty were field referees and 61 acted as
assistant referees. The data were collected from the referees and assistant referees who voluntarily
answered the interview during preseason, which was organized by the Union of Football Referees of
Santa Catarina (SINAFESC) in early 2011 in the city of Florianópolis (Santa Catarina - Brazil). A
semi-structured questionnaire was administered to the subjects during an interview by an
experienced researcher.
23
The questionnaire was proposed by Paes et al. (25). The questions were standardized in order to
precisely characterize the activities related to refereeing to account for only the sports injuries that
occurred in the three situations previously defined as: (a) during a soccer match; (b) during physical
training; and (c) during the physical tests applied by the FCF or Brazilian Soccer Confederation
(CBF). Injuries that occurred outside these three conditions were discarded. Moreover, the referees
were asked how many times they trained during the week, whether a professional monitored the
training, the average duration of the training sessions, when they began to officiate, and whether
they practiced soccer as a professional, amateur, or as a hobby before becoming a referee.
The definition of injury used in the present study was previously proposed by the Union of European
Football Associations (UEFA) (15), which was defined as pain or a complaint that resulted in the
removal from training, a physical test, or official refereeing. Five types of injuries were considered:
strain, dislocation, sprain, fracture, and contusion. The questionnaire also allowed for identifying the
injured referee who sought medical aid and physiotherapy. Finally, it was possible to collect the
necessary data to determine Body Mass Index (BMI).
The physical test applied by FIFA to measure aerobic capacity consisted of 20 rounds of 150 m in
30 sec with intervals of a 50-m walk in 40 sec. Anaerobic capacity was measured by applying six
sprints of 40 m. The exposure time in training was calculated based on the information provided by
referees during the interview. The exposure time in the physical tests was calculated in the same
way. However, in consideration of the fact that the FCF referees are tested twice a year by the
refereeing department, the FCF information was used to calculate the time spent in this situation.
On the other hand, if the data had not been stored, the exposure time in the matches was not
calculated. The risk of injury per 1000 hrs was calculated as 1000 x number of injuries divided by
the total number of hours spent in each of the aforementioned (21).
Statistical analysis was performed using SPSS (version 11, SPSS Institute, Chicago, Illinois). For
statistical processing of the data, descriptive statistics was initially used to group results in values of
mean, standard deviation, and percentage. Due to the small number of subjects analyzed, we
adopted the logarithmic conversion to non-standard variables, according to the Gaussian curve in
order to use parametric statistical parameters. The t test for independent samples was used to
evaluate the data. An alpha level of P≤0.05 was used to establish statistical significance.
RESULTS
The subjects’ main of age, weight, and height were 29 ± 7.55 yrs old, 77 ± 10.18 kg, and 1.79 ± 0.06
m, respectively. The subjects’ BMI was 24.30 ± 2.59 kg·m-2. Table 1 presents the anthropometric
evaluation of referees separated by function. Statistical analysis of the anthropometric data between
the referees and the assistant referees demonstrated a statistically significant difference between
the variables body weight (P = 0.0072) and height (P = 0.0007).
Table 1. Anthropometric Evaluation of Referees from Santa Catarina State by Function.
Age
Weight
(yrs)
(kg)
Referees (N = 40)
30 ± 6.0
80 ± 8.9*
M ± SD
Assistants (N = 61)
29 ± 8.5
75 ± 10.4
M ± SD
*Statistical difference between referees and assistant referees
Height
(m)
1.80 ± 0.1*
1.77 ± 0.1
BMI
(kg·m-2)
24.63 ± 2.0
24.07 ± 2.9
24
From the entire sample (N = 101), 36 subjects (35.6%) reported they had suffered 54 injuries during
their career. Of those injured, 26 subjects (72%) reported they obtained medical help for diagnosis.
Twenty-four (67%) of the 36 subjects received physical therapy treatment.
The most prevalent injury type investigated was the strains with 34 injuries, followed by sprains with
15 injuries. Three fractures, one dislocation, and one contusion were also reported. The places most
affected by injuries were posterior thigh muscles (14 injuries), followed by calf (13 injuries) and ankle
sprains (10 injuries). Other places were less affected by injuries, such as strain of the anterior thigh
muscles (7 injuries), knee sprain (6 injuries), tibia fracture (2 injuries), foot injury, and a dislocated
ankle.
The data indicate that the referees’ injuries occurred primarily during physical training. In fact, 21
injuries occurred during training while 19 occurred during the game and 14 during the physical tests.
The incidence of injury by 1000 hrs during physical tests was 314.38 ± 383 hrs and the incidence of
injury by 1000 hrs during physical training was 1.16 ± 1.40 hrs.
When compared with the assistant referees, it is clear in Figure 1 that the referees suffered more
injuries during the physical training (13 x 8) and during the matches (11 x 8). During the physical
tests, both the referees and the assistant referees had the same number of injuries.
14
12
10
8
Referees
6
Assistant
4
2
0
Training
Test
Match
Figure 1. Situations Where the Referees and Assistant Referees Suffered Injuries.
The referees reported the incidence of 515.35 ± 555.36 injuries per 1000 hrs during the physical
tests and 1.46 ± 1.72 injuries per 1000 hrs during training. The assistant referees had fewer injuries
during the physical tests (mean, 170.83 ± 82.60 injuries per 1000 hrs) and 0.73 ± 0.65 injuries per
1000 hrs during training.
The referees reported 10 sprains, 19 strains, and 2 fractures. The assistant referees reported 5
sprains, 15 strains, 1 fracture, 1 dislocation, and 1 contusion. The different locations affected by the
5 types of injuries are shown in Table 2.
25
Table 2. Types and Locations of Injuries in Soccer Referees in the Santa Catarina Soccer
Federation.
Injuries
Local
Referees
Assistant
Referees
Sprain
Ankle
Knee
9
1
1
4
Anterior thigh
Posterior thigh
Calf
6
6
7
1
8
6
Tibia
Ankle
Feet
2
0
0
1
1
1
Strain
Fracture
Dislocation
Contusion
The training frequency of the referees involved in this study (N = 101) was 3.0 ± 1.1 times·wk-1. The
time spent in training was 60 ± 26.17 min·session-1. There was no statistically significant difference
in the weekly frequency and duration of each training session between referees and assistant
referees (P>0.05). Seventy-seven (77) referees reported that they trained without the supervision of
a Physical Education Professional.
The referees who reported some type of injury were separated into three groups by age. The first
group was composed of referees aged between 20 and 29 yrs; the second group, with referees
between 30 and 39 yrs; the last group was composed of referees over the age of 40. The referees
over 40 yrs of age had the highest number of injuries (Figure 2). Of the 36 injured referees, 8 were
20 to 29 yrs of age with 11 reported injuries, 14 were 30 to 39 yrs of age with 21 injuries, and 14
were over 40 yrs of age with 22 injuries.
25
20
I
n
j
u
r
I
e
s
15
10
5
0
20-29
30-39
>40
Age group
Figure 2. Number of Injuries in Each Age Group of Soccer Referees by FCF.
26
When the referees were asked about their experience with soccer before becoming a referee, 24%
reported having practiced soccer professionally, 47% reported having practiced soccer in an
amateur way, 25% said they had contact with the soccer during their leisure time, and 4% reported
not have any contact with soccer (Figure 3).
35
30
25
r
e
f
e
r
e
e
s
20
Referee
15
Assistant
10
5
0
Professional
Amateur
Leisure
Figure 3. Experience Level of Referees as Soccer Player.
DISCUSSION
The referees in this study were similar in age, weight, and height to the referees in the Danish (22),
Italian (7), Chilean (16), Brazilian (12) and international (23) studies. The type and local of injuries
presented by the referees from Federation of Santa Catarina were similar to those presented by
Swiss (3,4), international (5) and Brazilian referees from Paraná state (25).
As described previously, ~36% of the 101 subjects reported that they had received an injury during
their career. Given the severity of the injury to the 36 referees, twenty-six (72%) obtained medical
help. Twenty-four (67%) of the 36 referees received physical therapy treatment. The highest number
of injuries in the referees and assistant referees occurred during the training sessions more so than
during the soccer match (Figure 1). Regarding the referees, this finding is in agreement with Paes et
al. (25) and Bizzini et al. (3,5) who also reported that the referees suffered more injuries during
physical training. But, in addition, Bizzini et al. (3,5) also reported that the assistant referees suffered
more injuries during physical training than during the match itself. Interestingly, though, in the 2011
study by Bizzini et al. (4), the Swiss referees reported that they were injured more during the match
games than during the physical training.
In regards to the types of injury, the present study offers some support of the findings in the Sul
American (25) and European (3-5) referees. Paes et al. (25), Bizzini et al. (3), Bizzini et al. (4), and
Bizzini et al. (5) reported that the referees and assistant referees suffered more muscle strains. All
injuries were affected by the referees in the lower limb. In fact, in 2002, Junge et al. (19)
investigated the injuries soccer players experienced during 64 games in the 2002 World Cup and
reported that the injuries affected predominantly the knee and ankle joints and the thigh and calf
muscles. Two years later Junge et al. (20) published another report that concluded 17% of the
injuries occurred mainly in the ankle, 16% in the thigh, 15% in the leg, and 12% in the knee (20). In
a 2011 study published in Brazil, Valente and colleagues (29) reported that injuries in soccer players
27
occurred primarily in the lower limb by way of sprains. These data showed that referees and players
are prone to develop predominantly lower limb injuries (i.e., from the hip to the foot). Therefore, it is
more than reasonable that prophylactic measures should be adopted by the referees to decrease
the risk of injury.
The referees reported that the physical preparation for refereeing consisted of 60 min·session-1 at an
average of 3 times·wk-1. The majority of the referees engaged in aerobic running to increase aerobic
power and intermittent races to increase anaerobic power. The training frequency, duration, and
type of physical activity used are consistent with the general recommendation for maintaining health
and well-being. The referees’ training was not designed to increase physical fitness at an athlete’s
level, which is consistent with the training of high class referees from Denmark who often engaged
in moderate intensity aerobic racing with a distance between 3 and 7 km (22).
The soccer match was the second condition in which the referees suffered more injuries while the
assistant referees showed the same number of injuries during the game and the physical training.
As the studies have developed, especially in Brazil (25) and Europe (3,5), researchers have
reported that field referees experienced fewer injuries during the game when compared to the
number of injuries during physical training. The only exception is the work of Bizzini et al. (4).
Referees presenting a high number of injuries during the physical training versus the game
represent an unusual situation, especially since the distance covered by the referees is similar to the
soccer players. In fact, as reported by Hägglund et al. (15), soccer referees typically cover distances
between 9 and 12 km during a match (15) while soccer players (particularly the midfielders) also
cover the same distance during a match. This similarity between the total distance covered by the
referees and players reinforces the idea that referees should be more physically prepared for their
work (11,30). After all, soccer requires the athlete have a high level of anaerobic capacity (speed
and muscle strength) to perform numerous motor actions such as during sprints with short recovery
periods (26).
According to Ekstrand and Nigg (14), soccer players can suffer injuries during the game due to the
use of inappropriate footwear, the unevenness of the field, and by physical contact. These factors
were also mentioned by several referees during the 2006 World Cup selection as possible causes of
their injuries (5). However, more often than not, when compared to the players’ injuries, the referees
who receive physical contact experience less risk of acute injury (3). This is because ~50% of the
acute injuries (especially with regards to the knee and ankle sprains) in soccer are caused by
physical contact with another player (19). The most common injuries without contact with another
player are sprains (especially the back of the leg), which are also common in referees.
The smallest number of injuries presented by both referees and assistant referees occurred during
the FIFA fitness tests (Table 1). These tests are performed on a track with a smoother surface than
the soccer field, which may justify the low number fractures and sprains. However, it is possible that
the referees may contribute to the muscle injuries (strains), given their desire to be approved. This
means at times the referees may push themselves beyond their safe physical capacity during the
physical tests.
Da Silva et al. (13) evaluated 209 professional soccer referees and reported that most were rejected
during the anaerobic test when it was applied before the aerobic test. After changing the order of
physical tests, Da Silva (10) found that a large number of professional referees continued to fail the
anaerobic test, which demonstrates that the referees were not prepared to perform an intense
28
anaerobic activity over a short period of time. Although there are no studies with injury data during
the physical tests in European referees (3-5), such information is extremely important.
Jones et al. (17) reported that soccer referees at the national and international levels should be
experienced at refereeing. The referees in the present study were on average 30 yrs old of age with
5 yrs of experience. The fact that the referees are generally 10 to 15 yrs older than the players
suggests that specialized physical training is important to help minimize the likelihood of getting
injured (30) while also improving their ability to conduct an official soccer match. Age is also an
important consideration, especially since an increase in age is highly related to more muscular
injuries (Figure 2). This point is supported by the Bizzini et al. (4) study of Swiss referees that found
the older referees had a higher number of injuries than the younger referees. Similar results were
reported by Paes et al. (25). Also, Arnason et al. (2) reported that increasing age increases the risk
factor for injury in soccer players. The age difference between players and referees is considered a
key factor among the international governing bodies of refereeing (FIFA and UEFA) (6).
When considering the findings in the present study, there is the limitation of the referees’ memory
bias (18,28). That is, it is always possible the referees remembered only the injuries that were
moderately severe or worse. Thus, the true incidence of injuries may have been underestimated.
CONCLUSIONS
The injury prevalence during training and physical testing is significantly higher than during the
game. Therefore, the associations should be more responsible for the development of preventive
training programs in the referee’s routine preparation for refereeing. In fact, the training programs
should be similar to the players’ physical training to help minimize the injuries that the referees
experience. After all, referees at all levels can continue until 45 yrs old, which is the age limit of
refereeing at the national and international level.
ACKNOWLEDGMENT
We would like to thank the referees Soccer Union of Santa Catarina (SINAFESC), in the person of
Mrs. Erica Krauss Gonçalves, secretary of this organization, which helped us to have access to the
referees and develop this work.
Address correspondence to: Dr. Alberto Inácio da Silva, Universidade Estadual de Ponta Grossa
(UEPG) – Ponta Grossa – PR, Brasil, Email: albertoinacio@bol.com.br
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