The instructor talks about a technique called white knuckles. White knuckles means creating tension with your hands. You'll squeeze the bar as hard as you can to create tension, and you'll see white knuckles. To learn how to do this take a jump stretch band and wrap it around your wrists. Now you'll have to spread your hands out and hold the bar as hard as you can so that your hands don't slip on the bar. This will also teach you to pull your hands apart to engage the last. Lie on the bench with the jump stretch band around your wrists. Stretch your hands apart and bench the weights. It will create more tension and help you to improve your technique.