| The weightlifting belt is often
considered standard issue in the weight room these days.
From the competitive weight lifters to those of a more
recreational interest, all would seem to agree that
there is a necessity for such a device. After all,
supporting the back in order to help prevent injuries
while lifting is a difficult point to argue. It is
because of this seemingly obvious benefit that the
concept is beginning to be used in other areas as well.
Besides the weight room, public and private industry
have begun to provide lower back support equipment for
their personnel. It is becoming more common to see these
devices on stock clerks, warehouse and construction
workers, as well as firefighters. While the intention is
certainly prudent, is it actually understood how weight
belts function to support the back? Do the weight belts
in the gym support the back in the same manner as the
back braces used in commercial environments? Is there a
time for wearing a weight belt or back brace that is
most appropriate? Furthermore, is there ever a
disadvantage to wearing a lower back supporting device
of any kind?
The answers to these questions could very possibly
alter the thinking as to the use of a weightlifting belt
or back brace. Likewise, the following information could
lead to a decision not to use a weight belt or back
brace at all.
The Function and Benefits of
Lumbar Support
Back braces differ from weightlifting belts in the
overall objective to support the back. In normal
populations back braces are successfully used to offer
support in conditions where low back pain reduction is
the primary goal. (1,2) Physical support as well as
psychological comfort have been noted with these
devices. (3) Even people that have not injured their
back often use these corset style braces to assist them
in carrying out their everyday lifestyles. It is the
rigidity of the brace itself that serves to immobilize
the area in a splint-like fashion thus lending support
to the lower back. (4,5,6,7)
The weightlifting belt, contrary to popular belief,
supports the back in a different manner. While there can
be some support due to the rigidity of a weight belt,
the benefit is minimal compared to the support offered
by the increase in the intra-abdominal pressure (IAP).
(8,9,10)
During a normal lifting maneuver such as the squat;
the diaphragmatic muscles along with muscles of the
torso contract generating pressure on the abdominal
cavity. The abdominal cavity together with its
predominantly fluid contents, known as the "fluid
ball", are kept under pressure by the surrounding
musculature. It is this natural intra-abdominal tension
that supports the spinal column. (11) Several studies
have shown that weight belts increase intra-abdominal
pressure and therefore assist in this natural
stabilization mechanism. (3,8,12,13,14) Other studies
have shown that increased IAP by use of the weight belt
not only relieves the load of the musculature of the
lower back, but also reduce the compressive forces on
the spinal discs. (15,16,17) Furthermore, it has been
reported that the reduction in these compressive forces
can be reduced by as much as 50% when utilizing a weight
belt. (16,18,19)
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Additional benefits exist with the use of the weight
belts due to IAP. Subjects demonstrated faster lifting
movement (12,13,20) , greater emphasis on hip extension
relative to knee extension (12) , as well as greater
comfort and sense of support. (12,13,17,20,21)
Potential Hazards of Improper
Usage
The use of both weightlifting belts and immobilizing
lumbar braces must be observed in terms of their
appropriateness. The fact that there are benefits to
wearing these devices tends to create the perception
that they should be worn at all times, during any
lifting activity. This is a myth that will only lead to
decreased performance and potential injury.
For instance, the significant increase in IAP and
thus the resulting benefit, has been shown to be with
heavier lifts of the 90% maximum (1RM) condition. (12)
Although during a set of higher repetitions (10 RM) it
is reported that while only 61% of the 1 RM is utilized
(22) , a possible significant effect of increasing IAP
may be considered a cumulative benefit if the last few
repetitions are close to failure. (13,17) It would be
easy to surmise from this information that wearing the
weight belt at all times would be the best insurance
policy.
However, electromyographic activity of the
stabilizing musculature is reduced when a weight belt is
worn which could lead to atrophy of the postural muscle
groups. (12,16,23) Injury potential is obviously higher
in muscle tissue that is devoid of the optimal training
stimulus.
Furthermore, lumbar support devices that increase IAP
must be tightened to be effective. High IAP, however,
may impede blood flow back to the heart (12) as well as
significantly raise blood pressure. (24) Wearing a
weight belt at all times would certainly appear
contraindicated when all the criteria are examined.
Recomendations
There has been a great deal of information cited above
regarding lumbar support devices. From these references
the appropriate use of a weight belt or back brace
should first be determined based on the person's
objective. The corset-style back brace is commonly used
for immobilization due to an injury. These are not
directly associated with the concept of stabilization by
increasing IAP and therefore could possibly be worn for
an extended period. Anyone wishing, however, to use a
brace of this type should consult their physician for
specific direction. Individuals who are free from acute
or chronic lower back pain may choose a lumbar support
device in order to prevent injury as well as assist
their own musculature for maximal strength enhancement.
In the gym environment the weightlifting belt should not
be worn at all times. The belt should only be utilized
for exercises that involve the spinal erectors against
high resistance i.e. squat and deadlift. (21) The belt
should be loosened after every set and the individual
should breathe between every repetition.
With proper training progression a person should
eventually wean themselves off of the weight belt (21)
and utilize the support device when intensities reach
80% of the person's 1 RM unless a set of multiple
repetitions is performed to failure. (12) It is
imperative, however, that training at lower intensities
continue without the weightbelt. This will help ensure
the natural stabilization and production of IAP (11).
In the industrial setting, the use of lumbar devices
is controversial. Requiring a lumbar support device to
be worn while on the job can actually be more of a
hindrance than a help unless a training program be
included. The training program should include proper
technique as well as an exercise prescription for
conditioning the body's natural stabilization mechanism.
For occupations such as fire fighting, the back brace
would not be logistically convenient or biomechanically
efficient simply by the nature of the unpredictable work
environment. The most prudent idea to truly protect this
special population would be a comprehensive hips and
trunk stabilization and conditioning program. Many
programs are targeted toward a healthy back when the
coordination of the hips and trunk should be the
ultimate focus. This is not to say that a weight belt
should never be used, but rather considered more of a
last resort where the appropriateness is carefully
scrutinized.
References:
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support in the treatment of low back pain. J. Bone Joint
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Spine, 17: 678-681; 1992
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response to loads applied to the torso in normal
subjects. Spine, 5: 149-154, 1980
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Spine; 11: 834-837, 1986
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