I commented on that last post explaining why I chose the Wall Sit as a key exercise in Hillfit Here is what I said:
I chose the Wall Sit / Air Bench / Wall Sit for Hillfit for a number of reasons.
First of all it is simple to learn. Too many trainers or internet personalities present exercises that may be fine but are actually complex motor skills. Kettlebell snatches and swings for example may or may not be good exercises but they are not easy to learn without decent coaching and a lot of practice. The Wall sit is different – it is a very simple move. Once in position your task is simple – hold that position until you can’t hold it anymore, sequentially recruiting the muscle fibres.
Secondly it is a congruent exercise (in terms of Bill DeSimone’s work). At the 90 degree knee position you are at maximum moment arm for the quads, while this is also the position of maximum muscle torque – the hardest position in terms of leverage is met with the muscle being at its strongest.
Thirdly it removes much risk. Whatever the squat defenders say you are in a risky position moving with a bar on your back. I’ve seen and experienced too many slips and accidents. I’ve seen people squat without collars only to see plates slide off the bar so it flips off and cracks them in the back of the head. I’ve seen people get stuck at the bottom. In terms of duty of care I cannot recommend this move to the average person that I aimed the book at. With the Wall Sit there can be zero added load or if you do add load you can do it safely – hold dumbbells at your side or in a goblet position.
In terms of performance I either just do the timed hold, adding weight if I go over 90 seconds, or do that and immediately go into the top half of a free /air squat, the easy portion where the moment arm is less and you can keep going. I also sometimes do them Max Pyramid style: 20seconds with knees at about 60 degrees, 20 seconds with knees at 90 degrees, then 90 degrees with added weight for 20s, add weight until you can’t hold for 20 then back down, usually backing to zero load and then the 60 degrees.
Wall sits were the basic quad exercise Bill DeSimone recommended in his first book, Moment Arm Exercise which was what got me thinking of them as the basic move.
For me for most people a wall sit, plus a plank (pushup position) would be the start of all training. I also add some timed static contractions now, but that is another story.
There is a good demonstration of a wall sit at 1:19 in this video from Patrick (who I interviewed)