The first thing I would do is make sure you are doing the PISTON squat, and not the Pistol squat. Two very different movements!
The piston squat is great for building the quads, while the pistol squat is a single leg movement requiring a lot of mobility and places a large amount of sheer force on the knee.
Here is a link to each movement
If you are in fact doing a PISTON squat, and are having knee pain, I would make sure that you are sitting back into the squat as you normally would, in order to tension the hamstrings. If you continue to have some knee pain, I think taking some time away from the movement, performing some corrective exercise like TKE and glute med activation to relieve the strain on the patellar tendon. It may not be the most optimal movement for you.
Paul is an elite level raw Powerlifter with personal bests of an 805lbs squat, 440lbs bench, 725lbs deadlift and a 1960lbs total in the 242lbs class, as well as an 800lbs squat, 430lbs bench, 700lbs deadlift and 1930lbs total in the 220lbs class.
Paul brings a deep educational background to the team as he has earned Master’s degrees in both Sports Management and Exercise Science. He is a former D1 Collegiate Strength and Conditioning Coach, who now works as a Functional Rehabilitation Specialist in Calgary, Alberta, Canada.
Paul provides coaching services in the areas of training and nutrition through his company Master Athletic Performance and is also the co-founder of a technology company, 1-Life Inc. Stay tuned for more information on that in the future!
If you have access to a leg press machine you can replicate a piston squat while playing around with foot position. I also like to use Bulgarian split squats for quad work. Backward sled drags are another favorite.
A self-proclaimed former high school band nerd turned meathead nerd, Lisa has been coached and mentored by Brian Carroll using 10/20/Life principals for 3 years. She started CrossFiting in 2006 but gave that up after realizing all she wanted to do was squat, bench and deadlift heavy. She now competes as a raw and multi-ply powerlifter in the 114 and 123 weight classes. Lisa has All-Time top 10 totals in both raw and multi-ply in her respective weight classes with a raw pro total of 936 lbs at 114 and a pro 1118 lb multi-ply pro total at 123 and 1090 lb multi-ply total at 114. She is currently ranked the #1 female multi-ply lifter at 123, #2 at 114 multi-ply female and #3 raw with wraps. Lisa has a B.A. in Political Science and a Masters in Public Administration, but hates politics and political debates. She is a mom of two, a firefighter wife and has worked as a full time litigation paralegal for almost 20 years.