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Here you will find an article on one exercise
(new one every month). With a detailed analysis of the
muscles used during the exercise and a informative description
of how to both perform and assist in the actual performance
of the exercise.
A full library of all previous exercises
can be found at members online under the sub menu
Exercise:
Back Raises
Client Instruction:
Starting Position
1. Lie in a prone position on the ground with your forehead
resting on your forearms and your elbows pointing out to
the sides
Up Phase (weight lifted)
2. From this starting position slowly raise your chest
off the floor while maintaining your neck in extension
3. Slowly continue to contract the posterior muscles of
the spine until the last part of your trunk making contact
with the floor is your “belly button”
4. If your “belly button” begins to raise off
the floor you have extended your spine beyond its safe limits
5. The trainer can kneel by your side and provide support
by lightly pushing your lower back down towards the floor
Down Phase (weight lowered)
6. Pause in the extended position
and then slowly lower your trunk back down to the floor
Muscle Analysis
High Cable Crossover
Muscle Analysis Back Raises
| Up Phase |
| Joint |
Action |
Contraction |
Muscle Group |
Specific Muscles |
| Spinal Joint |
Extension |
Concentric |
Spinal Joint Extensors |
Erector Spinae muscle group |
| Down Phase |
| Spinal Joint |
Flexion |
Eccentric |
Spinal Joint Extensors |
Erector Spinae muscle group |
Down Phase
In the down phase of the exercise the body is
lowered slowly with gravity. The muscles that concentrically
contracted to lift the body are the same muscles that are
eccentrically contracting to lower the body.
General Kinesiological
Analysis
The spinal extension is caused by the concentric contraction
of the erector spinae muscles. This muscle group is a collection
of smaller muscles that extend up and down the spine from
the skull to the sacrum and include the spinalis dorsi, longissimus
dorsi and the iliocostalis.
Advanced Kinesiological Analysis
The back raise is caused by the concentric contraction of
the longissimus dorsi, iliocosta-lis and the spinalis dorsi.
It is important that the amount of spinal extension caused
by the contraction of these muscles is limited to the axis
of rotation being located in the lower thoracic and the upper
lumbar regions. In the event that the spine continues to extend
below the recommended axis of rotation, there is now hyperextension
of the spine occurring. As the lumbar curve is concave in
shape, hyperextension causes an accentuated curve, resulting
in a narrowing of the exits for the spinal nerves. To prevent
this from happening, it is recommended that clients be told
to maintain their “belly button” and anterior
superior iliac spines (anterior pelvis) in contact with the
floor. This limits the extension to the thoracic and upper
lumbar regions. The erector spinae muscles are bi-lateral
muscles and as such are located on both sides of the spinal
column. This allows all these muscles to act as true synergists
throughout a variety of movements.
When one side of the muscle contracts, rotation or lateral
flexion movements can result. However, when both sides of
the muscle contract, spinal extension takes place. Exercise
Machine Variations Back raises can also be performed over
a bench. The client lies in a prone position with their hips
resting fully on the bench. The client must be square to the
bench so that their waist just clears the front. The client
begins the exercise by hanging their upper body over the edge
of the bench, while keeping their back straight. From this
starting position, the client maintains a straight back and
extends the trunk back to the horizontal position.
The hands are generally maintained to the side of the client’s
head. The trainer is positioned behind the client and holds
down the clients’ thighs. Many machines provide support
for the client’s lower body by fixing the ankles under
a brace. A variation to this exercise has the client roll-ing
up every vertebrae, rather than extending the trunk with the
spine in static extension. In all variations of back raises
it is important that the client does not rise above the horizontal
or further than full extension of the trunk.
Stability Ball Exercise Variations
Back raises can also be performed over a stability ball.
The client kneels down in front of the stability ball and
lies over the ball in a prone position. The client’s
chest and abdominals are in contact with the ball. This position
allows the client’s spine to roll forward assuming spinal
flexion. With their hands on either side of the ball, the
client attempts to extend their spine to a horizontal position.
The client lies in prone position with their hip joint and
abdominals in contact with the top of the stability ball and
their arms in front and supporting their body weight. From
this starting position the client can raise either one arm
at a time or alternating arms and legs. For example, the client
can raise their right arm and left leg with their left arm
and right leg supporting their body weight. The client can
then return back to the starting position and raise the opposite
arms and legs. The client can vary the back raise exercise
by lying in a supine position with their heels in contact
with a stability ball. The client splays their arms out to
the side of the body and perpendicular to the trunk. From
this starting position the client contracts their gluteals
and points their belly button towards the ceiling. This creates
a straight bridge between the client’s feet and shoulders.
The client holds this full extension position for a moment
and then slowly lowers the body back down to the ground.
Disclaimer: No responsibility is accepted for any loss
or damage suffered as a result of the use of the above
information
or any reliance on it. Users should satisfy themselves
as to their own or clients medical and physical condition
before adopting/using
the information or recommendations made. No responsibility
or liability is accepted for any loss or damage suffered
by any person as a result of adopting the above information
or recommendations.
Further information
1300 136 632 Phone +61 02 9212 7185 or Fax +61 02 9211
0002
Suite 505/410 Elizabeth Street Surry Hills 2010 Sydney
Australia
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