A benefit I can take from improving your squat form is that the lower you go, the more work you get. Getting low will give you more work which will end up making you stronger.
I would tell a classmate who falls short of 90 degrees to just work at getting lower each and every day. You won’t be able to get below that mark in just one day, but if you keep working at it you will eventually be able to get to it. Doing certain stretches that help your hips/glutes will help you get that lower squat.
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