To Stretch or not to Stretch: That is the Question
A Review of Evidence Presented for the Everyday Athlete
Injury. This word has been feared for generations among athletes of all ages, sizes, and abilities.
Any barrier that prevents you, the athlete, from enjoying physical activity that you love is always
detrimental. Physical exercise improves the way you feel, improves self esteem, and improves health.
Who doesn’t want to look toned, sleek, and attractive? Body image is such an integral part of self
esteem that any hindrance of keeping this image can be devastating. Various factors lead to injury but
since one human body is completely different from the next, it remains difficult to predict when you are
at risk for injury. Strength training for weak muscle groups, warm-up period, cool-down period, proper
nutrition and adequate rest have all been used as common approaches to staying injury-free
(Mackenzie). However, the particular warm-up method of stretching has never actually been proven to
prevent injuries; yet almost every coach will have their athletes perform a routine of stretching exercises
before a workout. The question arises, is stretching really beneficial; do you stretch or not?
Warm-up Period: time before exercise that gets muscles ready for movement
Cool-down Period: time after exercise that allows muscles to relax and wind down from exercising
Among many athletes, stretching before exercise is an integral part of their routine because
they believe this reduces the risk of injury (Pope, 1999). Athletes also stretch after exercise to prevent
muscle soreness before their next workout, but figuring out which way prevents the largest number of
injuries is where questions arise. The potential benefits derived from flexibility exercise include injury
prevention, reduced muscle soreness, skill enhancement, and muscle relaxation (Amako, 2003). Even
though these are valid factors to take into account, there is no evidence that pre-exercise stretching
does, in fact, reduce injury risk (Pope). “Although many athletes and trainers have recognized an
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apparent benefit, the evidence in the medical literature remains controversial” as to whether stretching
prevents injury (Amako).
What are we to believe? If you type “stretching before workout” into Google, this difference of
opinion is very apparent within the first few results. Headlines like




“Want a better workout? Don’t stretch before”,
“Experts: Don’t stretch before exercising”--USATODAY.com,
“The Right Reasons to stretch before exercise”, and
“How to stretch before a workout for dummies”
confuse anyone who looks at them since there is no direct answer. What is an athlete to do when the
all-knowing Internet does not give a direct answer?
In studies conducted on this subject, there is evidence that supports stretching as part of warmup, because it was effective in decreasing the number of injuries among subjects. For example,
stretching of the hamstring before an exercise routine reduced the number of lower extremity injuries in
infantry trainees by 42% (Hartig, 1999). Stretching as part of warm-up in football players decreased the
number of lower leg injuries by 51% (Cross, 1999). These large decreases in the number of injuries are
significant in that an individual can keep training for that big race or save money from going to the
doctor or maintain overall lifestyle.
Other studies, however, suggest that stretching does not have any influence on the prevention
of injuries. For example, stretching as part of warm-up before training for army recruits did not prove to
prevent injury; the difference between recruits who stretched and those who didn’t was only 8% (Pope,
1998). Another study found that stretching as part of warm-up did not prevent muscle injury in mice
when one leg was stretched and the other was not (Black, 2002). Do the benefits of stretching really
prevent injury or is the prevention in injury associated with another part of exercise?
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Table 1: Unresolved Issue
STUDY
Law and Herbert (2007)
*Hartig and Henderson (1999)
*Cross et al. (1999)
*Pope et al. (1998)
*Pope et al. (1999)
*Black et al. (2002)
*Verrall et al. (2005)
*Amako et al. (2003)
*Weldon et al. (2003)
Woods (2007)
CONCLUSION
Warm-up is effective, Cool-down is not
-13mm score (out of 100mm) for soreness in warm-up
group
-0mm score (out of 100mm) for soreness in cool-down
group
Warm-up is effective
-42% decrease in injury of hamstring muscle
Warm-up is effective
-51% decrease in injury
Warm-up is not effective
-8% decrease in injury of calf muscles
Warm-up is not effective
-10% decrease in injury (5 stretches for lower
extremity)
Warm-up is not effective
-9% decrease in injury
Warm-up and cool-down is effective
-70% decrease in injury of hamstring muscle
Warm-up and cool-down is effective
-64% decrease in muscle/tendon injuries (7 stretches
for lower extremity)
Inconclusive
-Studies reviewed did not provide enough evidence to
discern either way
Warm-up is effective
-Stretching should be implemented 15 min before
exercise
Table 1: This table displays the controversy over whether warming up before exercising decreases the
number of muscle, ligament, and tendon injuries. *Indicates studies that used stretching as their main
form of warm-up
This paper is designed to present the data found on this controversial subject and conclude
whether stretching as part of a warm-up or cool-down or both is effective in decreasing the number of
lower limb injuries in physically active adults. Eight research reports and two research reviews are the
studies included. The studies analyzed in this paper occur from 1998-2007 and consist of durations
ranging from 3 days to 4 years. The subjects analyzed in these studies include army recruits, football
players, recreational runners and walkers, and mice. The subjects for the human studies include adults,
male and female, ages ranging 16-50 year olds all healthy to undergo physical exercise with no previous
injuries. The methods used in the studies include separating the subjects into groups, those receiving
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stretching treatment and those not receiving stretching treatment. The type of stretching, warm-up, and
cool-down were restricted to lower limb exercises and stretches, upper limbs were not accounted for.
Injuries recorded from each study included injuries of the muscles, tendons, and ligaments associated
with the lower limbs. The definition of injury had to be defined as any exercise related incident that
required a visit to the doctor/infirmary.
Bibliography
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