If you want to see great results in the gym, build more muscle and get ripped, the squat is a non-negotiable. A heavy barbell squat hammers almost every muscle in your body while stimulating a lot of growth and a massive hormonal response—over time, including squats in your workout will help you gain more size and strength overall.

But with any complex exercise, there’s a lot of room for error and the squat is no exception. Here are the top 10 mistakes people make with squatting, why they’re bad and exactly what you need to do to avoid them.