|
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:
Barbell Lunge
Client Instruction:
Starting Position
1. Place a barbell across the top of your shoulders just
below the neck and resting on the shoulders
2. Stand upright with your feet approximately shoulder
distance apart
3. Keep your eyes focused straight ahead and your abdominals
and spinal extensors contracted
Down Phase
4. Begin the exercise by taking a smooth step forward with
your right leg, being careful not to overstride
5. Your right foot should be placed straight ahead, far
enough to allow approximately 90 degrees of flexion of your
right knee joint
6. Slowly lower your hips until your right thigh is parallel
to the ground. Keep your back straight at all times
7. Your right knee should be over your right foot
8. Your left leg should be bent and positioned behind your
body in astride position
Up Phase
9. After a short pause push off the balls of your right
foot and slide your foot back to the original starting position
10. Repeat the movement with your left leg forward
Muscle Analysis
Barbell Lunge (Up Phase – lead /load leg)
| Joint |
Action |
Contraction |
Muscle Group |
Specific Muscles |
| Hip joint |
Extension |
Concentric |
Hip Joint Extensors |
Gluteus maximus
Semitendinosus
Semimembranosus
Biceps Femoris |
Knee Joint |
Extension |
Concentric |
Knee Joint Extensors |
Rectus Femoris
Vastus Intermedius
Vastus Lateralis
Vastus Medialis |
| Ankle Joint |
Plantar Flexion |
Concentric |
Ankle Joint Plantar Flexors |
Gastrocnemius
Soleus
Tibialis Posterior
Flexor Digitorum
Flexor Hallicus Longus
Peroneus Longus
Peroneus Brevis |
Down Phase
In the down phase of the exercise the weight is lowered slowly
with gravity. The muscles that concentrically contracted to
lift the weight are the same that are eccentrically contracting
to lower the weight.
General Kinesiological Analysis
In up phase of a lunge, the lead leg is extended at the hip
joint, knee joint and plantar flexed at the ankle joint. Extension
of the hip joint is caused by the concentric contraction of
the gluteus maximus, semimembranosus, semitendinosus and the
biceps femoris. Extension of the knee joint is caused by the
concentric contraction of the vastus medialis, vastus lateralis,
vastus intermedius and the rectus femoris. Plantar flexion
of the ankle joint is caused by the concentric contraction
of the gastrocnemius, soleus, tibialis posterior, flexor digitorum
longus, flexor hallucis longus, peroneus longus and the peroneus
brevis.
Advanced Kinesiological Analysis
The barbell lunge is essentially a one legged squat. The lead
leg undergoes the greatest muscle activity, while the rear
leg is used to maintain balance. The prime movers of the hip
joint in the lead leg during a barbell lunge are the gluteus
maximus, semimembranosus, semitendinosus and the biceps femoris.
The prime movers at the knee joint are the vastus medialis,
vastus lateralis, vastus intermedius and the rectus femoris.
The prime movers at the ankle joint are the gastrocnemius
and the soleus. The assistant movers are the tibialis posterior,
flexor digitorum longus, flexor hallucis longus, peroneus
longus and the peroneus brevis. Some studies have reported
the increased recruitment of the adductor magnus and adductor
brevis in hip joint movements in the lunge. This is possibly
due to the increased fixation and stabilization required to
balance the barbell at the time the hip and knee joint extend.
Due to the astride position of the legs in the barbell lunge
there is a significant increase in the degree of stabilization
required to maintain balance. While the base of support of
the astride legs is adequate, the barbell resting on the shoulders
produces a counter current effect. This is not dissimilar
to someone walking a tightrope with arms to the side of the
body for balance. Lunges require a significant contribution
of the abdominals and the spinal extensors to stabilize the
trunk in order to prevent lateral flexion and an unbalanced
state. Clients learning to lunge for the first time are often
more suited to performing the exercise on a smith machine
until the required motor pattern has been developed. The stabilization
of the lead leg is also affected by the neutralization of
the semimembranosus and the semitendinosus causing medial
rotation of the hip joint, while the gluteus maximus and the
biceps femoris causing lateral rotation of the hip joint at
the same time they are all contracting together to cause hip
joint extension. The same can be said of the ankle joint.
When the full weight of the barbell is borne over the lead
foot, the tibialis posterior, the flexor digitorum longus
and the flexor hallucis longus will attempt to cause inversion
of the ankle joint, while the peroneus longus and the peroneus
brevis will attempt to cause inversion of the ankle joint,
while both sets of muscles contract together to cause plantar
flexion of the ankle joint.
Exercise Variations
A variation to the barbell lunge is the reverse lunge performed
on a smith machine. In this exercise, the client is positioned
under the bar in a smith machine. The client will stand initially
with both feet shoulder distance apart. From this position,
the client steps forward with the right foot. From this starting
position, the client will then swing their left leg forward
past the trunk to a hip flexion position. The client will
pause in this position and then swing the leg backward to
the original starting position, allowing them to assume a
lunge position. The client will lower their body weight in
the lunge position and then proceed to repeat the same exercise
again.
Stability Ball Exercise Variations
The client will stand with their back facing a wall. A stability
ball will be secured between the client’s lower back
and the wall. The client will place one leg in front of the
other before the commencement of the exercise. From this starting
position the client will sit back into the ball and lower
their body weight over the lead leg in a lunge position. The
lead leg will be flexed to 90 degrees before the client will
extend the lead leg back to the starting position. Once the
number of required repetitions has been completed the client
will perform the same movement on the other leg.
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
| |
