After everything is tight and you've got your hips set and your head up, take in a belly full of air, push out hard on your belt, and spread the floor with your feet. If you have done this properly, the bar will be out of the rack and you will still have the tight arch in your back. This is vital. If you aren't right here, your squat isn't going to be pretty. I guarantee it. The first few times that you get it done right, it will feel like you're going to cramp in your vastus lateralis and glutes. This is normal and goes away with practice. At many gyms, ours included, we call this "arching the bar out" of the rack. If you haven't done it correctly, you have done what we call "quadding the bar up."
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