To
Stretch or Not To Stretch
From
an interview with David C. Nieman, Dr. PH, FASCM, RCEP
Director and Professor of the Human Performance Laboratory,
Appalachian State University in NC, active researcher and
author of several textbooks on health and fitness
From:
ACSM (American College of Sports Medicine) Health and Fitness
Journal March/April 2003
Q: I read a news report recently that
claimed that research does not support the role of stretching
as a way to guard against muscle soreness and injury. Is this
report True? If so, then why stretch?
A: The news report you described referred
to a review article that appeared in the British Medical Journal.
(1) Two researchers from Australia reviewed all English-language
studies published between 1966 and 2000 that investigated
the effects of stretching before and after exercise on muscle
soreness, risk of injury, and athletic performance. Our of
hundreds of published studies, only seven were judged to be
of sufficient quality to be included in the review analysis,
They concluded that available evidence does not support the
role of stretching in preventing muscle soreness after exercise
or in reducing risk or injury.
Exercises to develop flexibility have long been pursued to
enhance performance, fitness, and peace of mind. The ancient
Greek athletes used flexibility training to enable them to
dance, perform acrobatic stunts, and wrestle with greater
ease. Stretching positions have been part of Near Eastern
and Far Eastern traditions for thousands of years and today
are practiced by millions in yoga classes to develop equilibrium
of body, mind, and spirit. Stretching has long been a vital
component of martial arts, gymnastics and ballet.
In the US, stretching became recognized as an important part
of a total fitness program after the publication of the book
Stretching by Bob Anderson in 1980. (2) This book has since
sold more than 2 million copies in the US and has been published
in 22 languages for worldwide distribution. In 1998, ACSM
included recommendations on flexibility exercise for the first
time in its position stance on exercise “based on growing
evidence of its multiple benefits” (3) ACSM recommends that
a basic stretching program be followed at least 2-3 days per
week and involve at least four repetitions of several static
stretches (in all major muscle/tendon groups) that are held
for 10-30 seconds at a position of mild discomfort.
FACTORS THAT INFLUENCE FLEXIBILITY
The word "flexibility" comes fro a Latin term meaning
"to bend". Flexibility is defined as the capacity
of the joints to move through a full range of movement. Flexibility
is specific to each joint of the body. Some people have flexible
shoulder joints, for example, but tight hip joints.
Why are some people more flexible than others? Each joint
is surrounded by ligaments, tendons, and muscles, and these
connective tissues determine whether the joint is tight or
loose (4). Ligaments are special tissues that tie bones together,
tendons link muscles to bones, and all of these together with
other tissues make up the structural connective tissues. Unusual
strain to the joint can stretch the ligaments, leading to
a loose joint that is then highly susceptible to injury. Stretching
exercises help to lengthen the muscles and tendons, increasing
the joint range of motion in a healthy way. Gymnasts and ballet
dancers, for example, are capable of amazing feats of flexibility
because they spend much time each day stretching.
As a person ages, flexibility decreases, although this is
thought to be caused more by inactivity than by the aging
process itself (4). There are good examples of physically
active elderly people who have maintained a high degree of
flexibility, and studies show that older persons can benefit
from flexibility training. In other words, it’s never too
late in life to perform stretching exercises. But the usual
tendency is for people to grow weak and tight as they age.
Gender also plays a role, with males tending to have less
flexibility than females.
FLEXIBLE BENEFITS
The concept behind stretching is simple: when a muscle is
extended slightly beyond its normal length (just short of
the pain threshold) it gradually adapts and develops a greater
range of motion. That improved range account for most of the
performance benefits of stretching. There is little double
that flexibility is important for performance by elite athletes
in such sports as Olympic weight lifting, ballet dancing,
gymnastics, swimming, track and field, and wrestling. Athletes
in these sports usually possess excellent range of motion
in the applied joints.
Is your flexibility important for injury prevention? Despite
the lack of good scientific evidence, the majority of sports
medicine specialists support the use of flexibility training
in injury prevention (5). Flexibility exercises also are advocated
in the treatment of many types of injuries to regain range
of motion and reduce pain symptoms. In other words, clinical
experience but not research has shown the practice of stretching
to be important for injury prevention and treatment.
Why the disagreement between clinicians and researchers? Part
of the problem is that this is a difficult area to research.
Flexibility is a complex trait that is highly specific to
the type of sport being investigated, the speed of the movement,
and the involved joint. When researchers attempt to study
the relationship between flexibility and injury prevention/muscle
soreness, they often use static range of motion measures that
may not translate to the specific dynamic flexibility demands
of the sport.
Besides, there are many other reasons to stretch, and it is
doubtful that most athletes are thinking of injury prevention
when they take time to stretch before and after exercise.
Reasons given for stretching include the following: (4,6)
· More graceful body movements
· Enhanced performance of sport skills
· Relaxation of mental stress and tension
· Muscular relaxation and relief of muscular cramps
and soreness
· Improved body fitness, posture, symmetry, and self-image
· Reduced risk of low-back pain and other spinal aches
and pains
· Rehabilitation/treatment of pain and injury
In other words, there are notable benefits
associated with the practice of stretching-so let's not stop
because a link to prevention of injury and muscular soreness
has not yet earned scientific endorsement.
References:
1. Herbert and Gabriel. Effects of stretching before and after
exercising on muscle soreness and risk of injury: systematic
review. British Medical Journal 325:468-472, 2002
2. Anderson. Stretching. Bolinas, CA:
Shelter Publications, 1999
3. American College of Sports Medicine.
The recommended quantity and quality of exercise for developing
and maintaining cardio respiratory and muscular fitness in
healthy adults. Medicine and Science in Sports and Exercise
30:975-991, 1998
4. Alter. Science of Flexibility. 2nd
ed. Champaign, IL: Human Kinetics, 1996
5. Higdon. True or false? Runners World,
April :100-105, 1997
6. Knudson, Magnusson, and McHugh.
Current issues in flexibility fitness. Presidents Council
on Physical Fitness and Sports, Readers Digest 3 (10), 2000
