Squeeze the bar with your hands and engage the muscles of your upper body and core.
How-to: Grab the pull-up bar with an overhand grip, wrapping your thumbs around the bar. “Play dead” — start in a dead hang from the bar. Squeeze the bar with your hands and engage the muscles of your upper body and core. Pull up until chin clears the bar. Slowly lower yourself back into the dead-hang position. Repeat.