A more complete set of mobility work for squatting
Calf/heel cord
This will allow unrestricted movement of the shin/knee over the ankle/foot.
You can do a version of this on the floor too, just push your bent knee as far forward over your toes as you can with your heel down, and lean into it.
something surprisingly simple to try.
Ball in the back of the knee from this
This also hits the hamstring a bit, but in general it's great to create some space back there.
Glutes
^be super aggressive with those, the key is to let your back leg hang and then to slump forward to add more load to the stretch. Some of the worst pain ever.
Hamstring
Hips
This stuff will also catch your quads, which is good. Also try this, where he puts the ball just above his knee. This is great for knee pain in conjunction with the ball in the back of the knee stuff.
Medial Hamstring
...and in general for people who find that having feet more parallel a problem (which is everyone, if it isn't you're lying
)
This stuff is extremely important.
Hip Capsule
...and something I do before every squat session that isn't "stretching" exactly, but it's kind of like these two
- done on the floor
so I'm forcing the femur into the back of the socket.