As most professional athletes would tell you, there is more
to athletic performance than the event itself. The elaborate
warm-up and cool-down rituals practiced by some athletes may
not be necessary for most people. But for anyone who is
physically active -- warming up, stretching and cooling down
are part of getting the most out of fitness activities. Yet
selecting safe and appropriate exercises for before and
after a workout can be confusing. And proper technique is
important because overstretching can do more harm than good.
So our patients/clients who are just beginning an exercise
program, or those who want to derive more benefit from their
present activities, will no doubt appreciate some
guidance.
Here's what they need to know for optimal exercise
performance. Warm-up is a term used to describe a variety of
activities that prepare people physiologically and
psychologically for athletic performance.
Warm-up exercises can be active or passive in nature. Active
warm-ups involve actual muscle activity while passive warm-
up warms the muscles with an external stimulus such as a
whirlpool or sauna. Passive warm-up neither adequately
stimulates nor warms deep muscle fibers and furthermore
diverts a large percentage of circulation to the skin. This
"theft" of blood away from the active muscles makes passive
warm-up a poor choice for enhancing performance.
Active warm-up exercises can include activities like
jogging, calisthenics or aerobic weight training. These
exercises may be further classified as either general or
task-oriented. General warm-up involves activities that are
unrelated to the specific event or task, while task-oriented
warm-up consists of exercises that use primarily the same
muscles as those needed for the athletic activity to be
performed.
For example, for baseball pitchers and fast bowlers
(cricket) performing calisthenics is a general warm-up
unrelated to the specific task of pitching. However,
throwing from the mound to the plate is task-specific and as
such, provides stimulation of neurological pathways
necessary for that movement.
When choosing a warm-up exercise to match a workout, it is
advisable to select both a general and a task-specific warm-
up. For example, in preparation for jogging, patients should
select a general warm-up such as calisthenics, followed by a
more task-specific exercise such as a slow jog.
Although the ideal intensity for warm-up exercise has not
been established, mild perspiration without fatigue is a
good guideline. A warm-up exercise prescription of 15-30
minutes is necessary for achieving adequate increases in
muscle temperature. The benefits of warm-up last for
approximately one hour. Since ambient temperature and
clothing will affect both warm-up intensity and duration,
the workout needs to be adjusted accordingly.
In summary, patients should be advised to: * Start slowly
and progress gradually. * Include both a general and a task-
specific exercise. * Perform warm-ups of sufficient
intensity and duration to produce mild perspiration without
fatigue.
Many studies have demonstrated the value of warm-up exercise
prior to engaging in moderate-to-heavy activity.
Physiologically, a warmed-up muscle produces faster and more
forceful contractions. Higher temperatures have also been
shown to speed up the transmission of nerve impulses. With
greater excitation and muscle recruitment, a higher level of
exercise performance can be achieved. Moreover, as the
metabolic rate in the muscle increases, oxygen more readily
dissociates from hemoglobin and is thus delivered to the
tissues more efficiently. Likewise, at a higher temperature,
muscle viscosity is reduced, allowing more proficient muscle
contractions. And as an additional benefit -- a warmed-up
joint is less subject to "gelling" of joint fluid than one
that has not been warmed.
The psychological benefits of warm-ups are more difficult to
assess but may include a reduction in muscle tension and an
improvement in task concentration. In our fitness programs,
particularly stretching, we have noted the patient's self-
assurance which is needed to successfully benefit from an
exercise session. Furthermore, we have observed that as
patients arrive for their exercise sessions, having traveled
or taken public transportation, their concentration is less
than optimal. After an appropriate warm-up and stretching
period -- they become more focused on the task at hand.
Most studies support the use of stretching as a means of
increasing flexibility and preventing injuries. The thermal
effect of warm-up may increase the elasticity and tear
threshold of specific muscle fibers. Therefore, stretching
exercises after a general warm-up may be beneficial in
reducing the possibility of stretching-related injuries.
Stretching exercises may be classified as follows: 1. Static
stretching is the safest and most effective stretching
method. These exercises are performed by holding a position
for a specific time period. 2. Passive stretching uses
forced motion to increase flexibility through stretching
with a partner. Team sports implement this type of
stretching to improve flexibility and promote team unity.
However, patients should be warned to take special care --
there is a risk of overstretching if the exercise is not
well supervised. 3. Contract/relax stretching also uses a
partner to stretch a particular muscle for a defined period
of time. The person then actively contracts the muscle group
isometrically against the partner. The isometric component
of this stretch can also evoke a valsalva maneuver which can
impair venous return to the heart and subsequently cardiac
output. Although isometric exercise is currently recommended
for some patients and is not as unsafe as previously
thought, it is important to consider the amount of isometric
exercise that is safe for a given patient who has
hypertension and/or coronary artery disease. In addition,
patients who undertake this type of contract/relax stretch
should be taught not to bear down while performing this
activity but instead to "breathe through it." 4. Ballistic
Stretching is a bouncing- rebounding movement, performed in
a rhythmical cadence. This type of stretching is not
recommended because it may actually increase tightness and
result in an injury.
So that the desired effect from stretching is achieved, each
stretch should be repeated 3-5 times, holding for 15-20
seconds. The most consistent gains in flexibility are
attained when stretching is performed daily -- before and
after each exercise workout. Patients should keep in mind
that certain areas of the body such as the Achilles tendon
and the elbow region are more prone to chronic inflammation
as a result of overstretching. Microscopic tissue tears and
formation of scars can increase vulnerability. Continued
over-stretching can lead to chronic inflammation.
Before starting any exercise program, patients who have had
previous medical problems or are at high risk for heart
disease should undergo a general medical examination.
Individuals who have cardiovascular or pulmonary disease
require low-level progressive warm-ups. Static stretching
can be used as a general warm-up -- followed by a task-
specific activity such as slow pedaling without resistance
for a full bicycle exercise session. Such a program limits
an early aerobic metabolism and thus prevents rapid
increases in heart rate which could otherwise induce
ischemia by augmenting myocardial oxygen demand in excess of
supply. Changes in weather conditions also require special
modifications in the selection of warm-up exercises. Heat
and humidity can artificially elevate patients' heart rates
and internal core temperatures -- causing increase in
metabolic rate. Therefore, intensity and duration of warm-up
exercises should be decreased at such times because a rise
in core temperature is easily achieved. In contrast, cold
environmental conditions, especially when complicated by
wind chill factors, require an extended warm- up. The goal
of warming-up in a cold environment is to increase muscle
core temperature sufficiently to make muscle movement
efficient and to warm up gelled joints to decrease the risk
of injury. Layered, lightweight clothing that provides
efficient passage of perspiration is recommended for colder
temperatures.
Physiologically, the cool-down phase of exercise allows
adequate venous return to be maintained during periods of
near-maximal peripheral vasodilation. If exercise is stopped
abruptly, blood pooling can occur in the lower extremities
and major muscles, reducing venous return to the heart. Such
a reduction can cause hypotension, syncope or arrhythmias.
Active muscle contraction and relaxation during cool-down
maintains venous return and cardiac output, thereby
minimizing the possibility of hypotension. Cooling-down
exercises allow circulation to be maintained promoting the
removal of lactic acid and other metabolic waste products
associated with the development of muscle soreness. Cool-
down exercises should be performed at a level of exertion
that is easy for the participant. The exercises should
continue until the exerciser's heart rate and respiration
have returned to near pre-exercise levels.
Activities during cool-down may include a slow walk or other
specific activity at a reduced level of intensity. It is
recommended that stretching exercises be initiated after
active cool-down during hot weather. We encourage patients
and friends to warm-up, stretch and cool down each time they
exercise. This can promote safer and more enjoyable fitness
participation. And patients who are having fun, performing
well, and minimizing their risk of injury are likely to stay
active and fit.
Stretching charts for flexibility, tension reduction and
relaxation now available. CALL: (02) 6527684
052865821
(c) 2001 Dr. Reuven Bruner. All Rights Reserved.
Unauthorized duplication or translation is prohibited
without prior consent.
Dr. Reuven Bruner, Ph.D. Health/Fitness/ Nutrition & Total
Lifestyle Consultant Fitness of Body & Mind ' (02) 652-7684;
(052) 865821 Fax: (02) 652-7227 Email:
dr_bruner@hotmail.com
