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Journal of Clinical Physiotherapy Research Review Article
Journal of Clinical Physiotherapy Research. 2019; 4(1): 1-8
Copyright © 2016 Shahid Beheshti University of Medical Sciences. All rights reserved. Downloaded from: http://journals.sbmu.ac.ir/physiotherapy/
Review on Identifying the Causes and Frequency of Weight-training
Injuries and their Prevention Strategies
Hamid Mahdavi Mohtasham abc, Shahin Salehi a*
a Sports Medicine Department, Shahid Beheshti University of Medical Sciences, Tehran, Iran; b Bone, Joint and Related Tissue Research Center, Shahid
Beheshti University of Medical Sciences, Tehran, Iran; c Lecturer, Iranian Bodybuilding & Fitness Federation; Tehran, Iran
*Corresponding Author: Shahin Salehi, Department of Sports Medicine, School of Medicine, Shahid Beheshti University of Medical
Sciences, Yaman St, Shahid Chamran Highway, Tehran, Iran. Tel: +98-21-22605090; E-mail: salehi2955@yahoo.com
Submitted: 2018-11-06; Accepted: 2019-02-13; DOI: https://doi.org/10.22037/english.v4i1.24569
Abstract
Introduction: The purpose of this study was to investigate the causes and frequency of weight-training Injuries. Methods: To conduct this
research, background research was performed using search engines from 1980 to 2018. In the next step, after excluding unrelated articles,
articles containing information on weight-training injury and prevention of sports injuries were selected. Results: The results revealed that
men are more injured than women. The major location of injuries in weight training was the upper part of trunk (25.1%), the lower part of
trunk (21%), hands (17.9%), legs (12.7%), and head (11.9%). Furthermore, the major types of injury were sprain and strain (47.2%). In
addition, most injuries from weight training occurred in ages 14-18 and 23-30 in hands and upper body respectively. Strain and sprain were
the most common injuries for 13-34. The injury was different in women; most injuries in women occurred from the ankle down and trunk.
Movements causing injuries included deadlift, squat, chest press, and overhead press. Conclusions: Injury occurred less in women compared
with men in strength training. Lower body was injured more than the upper body in women. Injury in those with 14-18 years old results from
lack of knowledge about the use of machines and fall of weights on limbs. On the other hand, those with 23-30 years of age tend to use
heavier weights which can lead to ligaments injuries. It is recommended that sports coaches teach correct and risky exercises to athletes for
injury prevention.
Keywords: Epidemiology, Resistance training, Weight training, Injury prevention, Sports injury
Please cite this paper as: Mahdavi Mohtasham H, Salehi S. Review on Identifying the Causes and Frequency of Weight-training Injuries and
their Prevention Strategies. J Clin Physio Res. 2019; 4(1): 1-8. DOI: https://doi.org/10.22037/english.v4i1.24569
Introduction
Resistance training is becoming popular for both professional
athletes and teenagers. (1) It could be done with free weights
(no external support), resistance machines, and other sports
facilities. Resistance training is used in different sports fields
such as bodybuilding, fitness, physique, Olympics
weightlifting, strongest men, powerlifting, CrossFit, and
sports specific strength and conditioning. This type of
training, especially use of weights, could cause muscular and
skeletal injuries such as fractions, dislocation, spondylosis,
hernia, and meniscus (2).
Many people participate in weightlifting, strength
training, and bodybuilding and nowadays musculoskeletal
injuries have become an important problem. (2) Injuries
related to weight training are of two kinds: the first which is
more common occurs while moving weights when too much
pressure is on the muscle and causes injury. The second is
weight room accidents when participants are struck by falling
weights or trip over equipment on the floor (1, 2).
Becoming familiar with exercises done by athletes who
become seriously injured with weights could help doctors in
taking accurate history (1). The mechanism and cause of
injury depend on the method of exercise though many
injuries are similar (1). Preventing injury is a goal of
primary care. The first step of prevention is awareness and
gaining enough knowledge about prevalence and causes of
injury in an exercise. Information on weight injuries is
2 Mahdavi Mohtasham & Salehi
Journal of Clinical Physiotherapy Research. 2019; 4(1): 1-8
Copyright © 2016 Shahid Beheshti University of Medical Sciences. All rights reserv ed. Downloaded from: http://journals.sbmu.ac.ir/physiotherapy/
Figure 1. Flow chart of the study selection process for eligible studies in the review article
provided from emergency, orthopedics (3-6), physicians,
sports coaches, and bodybuilding coaches’ reports (7). Also, a
better understanding of risk factors is required for gaining
more information about injuries (8). Accordingly, the
purpose of the present study was to determine resistance
training and bodybuilding injuries that occur because of
weight training.
Materials and Methods
This study was a review of studies on the causes and
prevalence of bodybuilding injury and methods to prevent
them. Information was collected using search through articles
published within 1980-2018.
Databases used included PubMed, ISI Web of Knowledge,
Scopus, Google Scholar, and ProQuest using Search query of
sports injury, weight training injury, preventing sports injury.
After finding the articles and eliminating unrelated items,
articles with information about sports injury and their
prevention were analyzed (Figure 1).
Results
The number of people participating in resistance training is
progressively growing, hence the number of people at risk of
injury also increases (9). Several studies have been conducted on
weight training injuries in children and teenagers (11-7), adults
(3, 9, 12), and athletes (9, 13, 14).
Keogh and Winwood (2016) analyzed injury in weight
training and found that the most commonly injured anatomical
locations included: shoulder, back, knee, elbow, wrist, and hand,
with the most common types being sprains and strains (15).
Brown and Kim (1983) report that 28 of 71 athletes were
injured. These 28 had 98 injuries whose cumulative frequency
was 39.4%, with the mean participation of 17.1 months (7).
The study of Risser et al. in 1990 with the purpose examining
weight training injuries in 354 athletes showed that 25 athletes
were injured. The cause of the low injury rate was the
supervision of coaches on athletes during exercises (8). Also,
Zemper in 1990 did a study for four years on 297088 athletes.
During this time, only 34 athletes were injured by weight
training. The reason was the presence of professional coaches in
Identify the Causes and Frequency of Weight-training Injuries 3
Journal of Clinical Physiotherapy Research. 2019; 4(1): 1-8
Copyright © 2016 Shahid Beheshti University of Medical Sciences. All rights reserved. Downloaded from: http://journals.sbmu.ac.ir/physiotherapy/
Figure 2. Injury rates by the anatomical location in children (left) and adults (men and Women on the right)
Figure 3. Special belt for strength training; internal pressure is increased during lifting weight and belt causes external pressure. The sum causes
an increase in power, more stability, and supports the back and trunk thereby allowing an athletic to lift more weight. Right) powerliftingbelts.org
2017, Left) gelisimalani.com 2018
include technical errors, immature skeletal structure, and abuse
of anabolic steroids. Acute injuries in weight training include the
training sessions (12). Squat, deadlift, chest press, and shoulder
press are the most injury-inducing exercises (7, 8, 12, 16).
Sudden accidents in the gym could also cause injury. When
athletes move between machines, weights might fall on them by
others (12, 17). That is the reason why the proper distance
between machines is necessary. In the following, the results of
the studies are reported based on three groups of severity of
injuries, age group, and gender.
Discussion
Injury Severity
Acute Injury
Musculoskeletal injuries from exercise have been important for
several systems such as the Consumer Product Safety Commission's
report (2, 18). Possible risk factors for injuries sprains, dislocation,
tendon avulsion, and compartment syndrome. Further, it is possible
that problems other than musculoskeletal injuries such as retinal
bleeding and cardiovascular problems would occur (1).
4 Mahdavi Mohtasham & Salehi
Journal of Clinical Physiotherapy Research. 2019; 4(1): 1-8
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Figure 4. Biceps curl with a dumbbell, where anterior arm forces forearm and pushes it upward. Now if shoulder joint is not fixed, the scapula
goes forward (A) and the movement is incorrect; the force is not efficient which leads to increased injury in the shoulder region. By contrast,
shoulder fixation gives rise to efficient force and the lowest risk of injury (B).
Figure 5. Women-specific exercises in specific warm-up: all exercises are isometric. Hold for 10 seconds and three sets with rest for 20
seconds in between sets
A study by injury supervision National Electronic Injury
Surveillance System (NEISS) in 1987 was performed on 64
emergency units in the US. The goal was to study referral to
emergency for sports injuries. The results indicated that annually
17000 injuries from strength training occur in 10-19 years old
which cause referral to the emergency room with most of these
injuries occurring at home (17, 18). In a study in 1985 for sports
injuries, 5.6 million people under 20 referred to the emergency
room in that year in the US (19).
Chronic injuries
Strength training is usually done with heavy weights and
should be done for a long time for achieving the desired
results. This is a cause of chronic injuries. Rotator cuff
muscle tendon inflammation, pressure injury to a vertebra,
and clavicle injury are the most common chronic injuries.
Also, muscular hypertrophy, poor technique, or overuse of a
muscle could cause muscular injuries such as thoracic outlet
syndrome or suprascapular neuropathy. Further, clinical
Identify the Causes and Frequency of Weight-training Injuries 5
Journal of Clinical Physiotherapy Research. 2019; 4(1): 1-8
Copyright © 2016 Shahid Beheshti University of Medical Sciences. All rights reserved. Downloaded from: http://journals.sbmu.ac.ir/physiotherapy/
chronic problems also occur in weight training, with the
most common being vascular stenosis, weight lifter's
cephalgia, and hernia (20).
For maximizing their athletic performance, athletes
perform weight training with heavier weights. The poor
technique causes extra pressure on rotator cuff when lifting
the weight which gives rise to shoulder injuries in athletes.
Teaching proper techniques of weight lifting could lessen
injuries (21).
Specifically, 36% of professional weightlifters who
attend competitions have one spondylosis in their spine
(20, 22). The prevalence of patellofemoral or tibiofemoral
osteoarthritis in weightlifters has been reported as 31%;
in competition runners, it has been 14%; and
patellofemoral arthritis has been more prevalent in them
(28%) than in football players (20, 23). Also, pressure
fractions in the forearm, arm, and sternum in
weightlifters are more common (20, 24-27). Further,
studies have shown that weightlifters suffer headaches
while lifting weights (20, 28-30).
Age group
Use of weights can lead to various injuries in adolescents
and teenagers (2) with most injuries occurring among 13-18
(9). Athletes under 18 who have not reached full bone
growth are prone to wrist and distal epiphysis of forearm
(radius and ulna) fracture due to lack of control in shoulder
press exercise (3-5).
It has been seen that short-term strength training
conducted under the supervision of a teacher for elementary
school students could prevent adverse effects on growth,
flexibility, the performance of motor control, bones, and
muscles, leading to low injury prevalence (31, 32).
Risser et al. in 1990 completed a study of weight training
injuries among teenagers. A total of 354 teenagers and
adults participated in the study and completed the injury
questionnaire. The participants were divided into 3 groups
with mean ages of 13, 15, and 17. The most common
injuries were muscle rupture (74.1%) in the back (59.3%).
The results revealed that the most dangerous exercise in 13
was chest press (95.2%), shoulder press (54.1%), and squat
(42.9%). The most injuring exercises in 15 were chest press
(95.7%), squat (72.3%), and shoulder press (71.9%). Finally,
in 17, chest press (97.9%), shoulder press (87.6%) and squat
(73.2%) (8) were the most damaging exercises.
Brown and Kimbal studied 71 participants across young
adult weightlifting competitions. In their view, the
definition of injury is any athlete missing one day of
training because of sports injury. They found that the most
common anatomical location of injury was lower back
(>50%) with musculotendinous injury (inflammation,
strain, and cramps). The mean lost time for each injury was
11.5 and the total lost time for all 98 injured people was
1126 days (61%) (7).
In Risser et al. study on sports injury among teenagers
and adults, the absence of more than 7 days was the
baseline. Further, the results showed the most prevalent site
of injury as lower back (48%) and strain with 74% (8).
In Zemper et al. study on injury among 10908 adult
football players for 4 years through data collection by
Athletic Injury Monitoring System (AIMS), sports injury
showed the common injury as strain (44%) in the lower
back (44%) (12).
Other studies on different age groups suggested that
more injuries occur in young adults (3, 7, 8, 11, 33). The
common anatomical locations of the injury were lower back,
leg (3, 7, 8, 11-14), and shoulder (11, 34) by strain (8, 12)
(Figure 2).
Gender
Men and women differ in terms of musculoskeletal and
metabolic features. Women’s bones are relatively smaller,
shorter, with less density. Thus, stress fractures are more
probable for them. Women’s pelvis is wider whereby the
body center is lowered and balance is increased. However,
a wide pelvis causes increased valgus angle in the hips
causing hip injuries, iliotibial tendonitis, and trochanteric
bursitis. Also, wide pelvis leads to Q angle changes. This
change and weak quadriceps cause the patella to go
outward. This, in turn, increases patella chondromalacia in
women. Also, women’s ligaments are looser because of
relaxing hormones resulting in looseness in joints. Loose
joints and increased Q angle promote knee injuries in
women (35).
Injury in men was 82.3% and the mean age of injured
27.6 years (9). Also, other studies showed that most injuries
of weight training occur in men (33, 36). Men in strength
training are more affected by sprain and strain injuries, but
women have more accidents in the gym. The trunk is the
most commonly injured anatomical location followed by
limbs which are injured more in women (37) (Figure 3).
6 Mahdavi Mohtasham & Salehi
Journal of Clinical Physiotherapy Research. 2019; 4(1): 1-8
Copyright © 2016 Shahid Beheshti University of Medical Sciences. All rights reserved. Downloaded from: http://journals.sbmu.ac.ir/physiotherapy/
Injury Prevention
All practice educations for all ages should be based on
technical skills and maturation. Further, qualified
professionals and coaches aware of strength training
educations should work with these age groups (38).
Conclusion
Based on the review article, men get more injured than
women in strength training. Injuries occur more in 14-18
and 23-30 years old. A common cause of injury in 14-18 is
lack of knowledge about exercise machines causing weights
to fall on limbs. However, among 23-30, the main cause of
injury is the tendency to increase weights resulting in
sprains and strains in the trunk. Hence, bodybuilding
coaches and sports professional can prevent injuries by
teaching proper exercise to athletes.
Review article suggestion
The timing of strength training
American children academy suggests the best time for
strength training with free weights in teenagers with the
onset of secondary sex features (39). At this age, some
epiphysis such as wrists has become complete and not
vulnerable anymore (2).
Gym and exercise machines
Resistance training salon should be large, cool, and air-
conditioned. Exercise machines should be in place and not
left in the salon and should be checked regularly to be
replaced and repaired in case of any breaks. Equipment
should fit the athlete’s size and age. Nowadays, equipment is
designed for teenagers and young adults and should be used
in gyms.
Use of exercise machines and resistance band are safer
for beginners. When people have basic physical readiness
and nerve-muscle coordination, they can use free weights
(2). It should be mentioned that injury could occur by
machines; therefore, the proper use of machines and
exercise should be taught and light weights should be used.
Also, the tempo of exercise should be slow and controlled
(40).
Special training belts are used for lifting heavy weights. It
is believed that contracting the abdomen and the increase in
abdominal pressure lessens the pressure to the vertebra
(Figure 3). This has been proved in the squat (41). Note
that weightlifting belts have flaws. If used regularly, they
might prevent abdominal and back muscle growth. Also,
their application is not possible for some weight training.
For example, in the snatch, the barbell might get stuck to
the belt. Further, the pressure of the belt on upper
abdominal part prevents blood flow to the heart; therefore,
the belt should not be used for this exercise (41). Lender et
al. (1990) recommended the use of special belts in exercise
with more than 80% weight for an individual. The belt
should be loosened between sets. Special belts are divided
into two groups. The first group consists of light belts of
7mm and 100mm width for beginners. The second group is
heavy 3-layer belts with 11mm and 100mm width for
professionals (41).
Many people do weight training for fun and leisure.
Some exercises are done at home. The technique should be
correct and heavyweight lifting needs an assistant. If the
pressure gets too much, the exercise should be stopped
immediately and weights should be reduced. If the pain is
present, the athlete should refer to the doctor ASAP (2).
Technique
The proper technique could help with injury prevention.
During exercise, the athlete should contract his/her core
muscles relatively, activate muscle stabilizer, exhale during
the contraction, and inhale when returning to the baseline
and perform the weight with control. Also, it is better for
the exercises to be performed under the supervision of a
coach (40) (Figure 4 (42)).
Physical examination
Before weight training, a doctor should examine athletes
physically. Some health problems limit weight training.
Some structural problems such as crossed legs predispose
the athlete to a knee injury. Further, musculoskeletal
problems might occur that could be prevented by
examination such as a seizure (43), cardiac diseases (44) and
high blood pressure (45).
Warm-up and cool-down
Before exercise warm-up is needed. The main purpose of the
warm-up is making the body ready for heavy activities and
preventing injury by specific exercises. The warm-up should
Identify the Causes and Frequency of Weight-training Injuries 7
Journal of Clinical Physiotherapy Research. 2019; 4(1): 1-8
Copyright © 2016 Shahid Beheshti University of Medical Sciences. All rights reserved. Downloaded from: http://journals.sbmu.ac.ir/physiotherapy/
be general and specific. First, in general warm-up, the
athlete performs a general exercise such as static stretches
with low intensity to prepare big muscles for activities.
Then, with running in place, they increase the central body
temperature. Then, specific warm-up is required. The coach
or athlete should choose the exercises by considering the
plan for the training. Women’s bodies are different and
some injuries might occur because of their structure; hence
women should perform some specific exercises at the
beginning of this warm-up (Figure 5). Then, they should
practice the warm-up like men. For example, on Saturday,
the goal of the training session is to strengthen chest
muscles. Exercises include circular shoulder joint
movements, elbow, and wrist with medium speed. Then. the
main muscles (chest) and accessory muscles (deltoid and
triceps) get ready with one to two sets of light weight
exercises. After the training, the athlete should cool-down
with light exercise for better recovery and decreasing
exhaustion (46).
Acknowledgments
Hereby, we extend our gratitude to the people for assisting
us in this research project.
Conflict of interest:
None
Funding support:
None
Authors’ contributions:
All authors made substantial contributions to conception,
design, acquisition, analysis and interpretation of data.
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