When to Stretch - Experts Recommend Static Stretching After Exercise
Static Stretch best after exercise; dynamic warm up best before
Recommendations to stretch or not stretch change from year to year and
from expert to expert. Stretching has been promoted for years as an
essential part of a fitness program as a way to decrease the risk of
injury, prevent soreness and improve performance. While researchers
continue to look at the benefits and pitfalls of stretching, there is
still limited (and conflicting) evidence to sort out these opinions.
Some research suggests that stretching doesn't prevent muscle soreness
after exercise. Researchers Robert Herbert, Ph.D., and Marcos de
Noronha, Ph.D. of the University of Sydney conducted a systematic review
and meta-analysis of 10 previously published studies of stretching
either before or after athletic activity. They concluded that stretching
before exercise doesn't prevent post-exercise muscle soreness. They
also found little support for the theory that stretching immediately
before exercise can prevent either overuse or acute sports injuries.
Research physiologists at Nebraska Wesleyan University made the headlines in 2009 when they published study results indicating that more flexible runners had lower running economy (how
efficiently they use oxygen) than runners with tight hamstrings.
Consequently, those runners were faster than the 'flexible' runners.
Yes, it was a very small study, and yes, they only measured sit and
reach scores. But the results were still a bit surprising and brought
more attention to the question: To should or not to stretch ?
Much of this confusion comes from a misinterpretation of research on
warm up. These studies found that warming by itself has no effect on
range of motion, but that when the warm up is followed by stretching
there is an increase in range of motion. Many people misinterpreted this
finding to mean that stretching before exercise prevents injuries, even
though the clinical research suggests otherwise. A better
interpretation is that warm up prevents injury, whereas stretching has
no effect on injury.
If injury prevention is the primary objective the evidence suggests that
athletes should limit the stretching before exercise and increase the
warm up time.
Studies do support that range of motion can be increased by a single
fifteen to thirty second stretch for each muscle group per day. However,
some people require a longer duration or more repetitions. Research
also supports the idea that the optimal duration and frequency for
stretching may vary by muscle group.
The long-term effects of stretching on range of motion show that after
six weeks, those who stretch for 30 seconds per muscle each day
increased their range of motion much more than those who stretched 15
seconds per muscle each day. No additional increase was seen in the
group that stretched for 60 seconds. Another 6 week study conducted
found that one hamstring stretch of 30 seconds each day produced the
same results as three stretches of 30 seconds.
These studies support the use of thirty second stretches as part of general conditioning to improve range of motion.
When sorting out all the research on stretching and flexibility for
athletes, it's important to remember that the goal of stretching is to
develop and maintain an appropriate range of motion around specific
joints. It's also important to realize that stretching (or releasing)
tight muscles should go hand in hand with strengthening the weak
I'm sure we'll continue to see headlines for and against stretching, but
if you choose to stretch, it may be best to customize your routine to
fit your needs. Assess your body and your sport and make sure you
stretch (and strengthen) in order to reduce muscle imbalances.
After exercise, cool down and hold a given stretch only until you feel a
slight pulling in the muscle, but no pain. As you hold the stretch the
muscle will relax. As you feel less tension you can increase the stretch
again until you feel the same slight pull. Hold this position until you
feel no further increase.
If you do not seem to gain any range of motion using the above
technique, you may consider holding the stretch longer (up to 60
What Stretch is Best?
In general, Proprioceptive Neuromuscular Facilitation (PNF) stretching
has resulted in greater increases in range of motion compared with
static or ballistic stretching, though some results have not been
Static stretches are a bit easier to do and appear to have good results.
Studies indicate that continuous stretching without rest may be better
than cyclic stretching (applying a stretch, relaxing, and reapplying the
stretch), however some research shows no difference.
Most experts believe ballistic, or bouncing during a stretch, is
dangerous because the muscle may reflexively contract if restretched
quickly following a short relaxation period. Such eccentric contractions
are believed to increase the risk of injury.
In addition to improving range of motion, stretching is extremely
relaxing and most athletes use stretching exercises to maintain a
balance in body mechanics. But one of the biggest benefits of stretching
may be something the research can't quantify: it just feels good.
Herbert RD, de Noronha M. Stretching to prevent or reduce muscle
soreness after exercise. Cochrane Database of Systematic Reviews 2007,
Andersen, J. C. Stretching Before and After Exercise: Effect on Muscle
Soreness and Injury Risk. Journal of Athletic Training 40(2005): 218-220
Witvrouw, Erik, Nele Mahieu, Lieven Danneels, and Peter McNair.
Stretching and Injury Prevention An Obscure Relationship. Sports
Medicine 34.7(2004): 443-449
Ian Shrier MD, PhD and Kav Gossal MD. The Myths and Truths of
Stretching: Individualized Recommendations for Healthy Muscles, The
Physician and Sportsmedicine, VOL 28, #8, August 2000.
Trehearn TL, Buresh RJ.. Sit-and-reach flexibility and running economy
of men and women collegiate distance runners. J Strength Cond Res. 2009