A very frequent question is how low should we squat. According to many you should go as low as possible, when your bum is almost riding on your heels. Most people don’t do that and use as excuse the eventual knee injury. The truth is that by stopping when your thighs are parallel to the ground, you’re putting the same amount of stresson the knees, if not even more.
The actual reason most people stop there is because, if you go past the thighs being parallel to the ground, your quads stop working and the hamstrings take over. The hams are far weaker than your quads, and thus you have to use lighter weights. However, if you develop your hams, your squat will soar and reach new heights that you would never be able to achieve by only squatting to parallel. In addition, when going as low as possible, you are also working your glutes. If your bum is flat and limp, you should definitely consider changing the way you squat. The lower you go, the faster you’ll achieve a nice, ample musculature.