Hang from a chin-up bar with both arms fully extended using a grip slightly greater than shoulder width. Allow the legs to hang straight down. From this starting position, bend your knees and raise your legs until the torso makes a 90-degree angle with your thighs. Hold the contraction for a second before slowly returning to the starting position. Keep the arms straight and the trunk perpendicular to the ground throughout the range of motion to avoid swinging the legs and torso.