If you’ve got an existing injury or previous reconstruction of the PCL, it is best to restrict flexion (bending your knee) to 50°to 60°so that posterior shear force is minimized as much as possible.
If you are wanting to work your quads their development is maximized by squatting to parallel, with no additional activity seen at when you go deeper into the squat.
However hip extensor movements increase with increasing squat depth, so full squats may be beneficial for those seeking to maximize strength of the hip musculature i.e. glutes.
How fast should I squat?
The speed of the movement should be based on goal-oriented
Specificity to the force-velocity curve. However, given
that speed of movement has been shown to significantly
increase both compression and shear forces (You want to minimise this as much as possible) , there is a trade off between optimal transfer of performance and
risk of injury. This is especially true on the eccentric aspect (going down into the squat)
of the squat where rapid deceleration generates exceedingly high joint forces at the knee.
Failure to control this descent can result in the ballistic contact between the hamstrings and calf muscles,
which can cause a dislocating
effect on the knee ligaments. Therefore, unless
your goals specifically dictate otherwise, squat descent
should always be executed in a controlled fashion, with
a 2 to 3 second eccentric tempo is a good rule of thumb.
Additional muscles you can target when squatting-
A wider stance squat is preferable for those seeking optimal
development of the hip adductors and hip extensors.
Where as a closer stance is more appropriate for targeting
development of the gastrocnemius.
Stance can also be varied to alter joint-related forces: a narrow stance helps to
minimize patellofemoral and tibiofemoral compression
while a wider stance results in less forward knee
translation and thus reduces shear force.
Low bar or high bar?
Low bar back squats tend to produce greater hip extensor
torque and a decrease in knee extensor torque compared with high
bar back squats. However, the magnitude of forces for both
movements are well tolerated by the associated joint
structures.
This means it is down to personal preference where you decide to have the bar
The front squat produces significantly lower
knee compression and lumbar stress in comparison with
back squats, making it a viable alternative for those
suffering from various knee and back pains.
Low bar or high bar?
Low bar back squats tend to produce greater hip extensor
torque and a decrease in knee extensor torque compared with high
bar back squats. However, the magnitude of forces for both
movements are well tolerated by the associated joint
structures.
This means it is down to personal preference where you decide to have the bar
The front squat produces significantly lower
knee compression and lumbar stress in comparison with
back squats, making it a viable alternative for those
suffering from various knee and back pains.
Fatigue can have a detrimental effect on squatting
technique, potentially leading to knee instability and
increased lumbar shear force. Therefore you may want to think twice about one last rep.
So there you have 6 tips you can utilise next time it's leg day to help you get where you want to be. If you would like more help with your squat click below to book in with a session... for further reading the paper I used is
Schoenfeld, B. J. (2010). Squatting kinematics and kinetics and their application to exercise performance. The Journal of Strength & Conditioning Research, 24(12), 3497-3506.