From manual shaft stretching to jelqing penis enlargement exercises to Either way, jelqing penis enlargement exercises are mainly used to increase the girth. Mar 24, - Here's a rundown of some unproven options to increase penis size. The vacuum pump. This is a cylinder that sucks out air. Stretching with weights. Weights or stretching exercises won't bulk up your penis -- it's not a muscle. Pills, supplements, ointments, and creams. They don't work.