somone told me that I straighten my legs even before the lift starts, and he's right. I guess I need to correct that. I agree that ma lower back could be more straight... I will try next time
That's hams and glutes. Be sure to drive through the heels, not just pick the weight up. Most people lack that posterior chain strength and the quads just shoot your load off early. As I type this the vid is no longer up so I couldn't see it.