As a general rule: The higher your erection level, the less flexible your penis, and the more intense the exercise. In the beginning, you’ll want to jelq with an erection level between 40 and 75 percent. Jelqing with less than 40 or 50 percent is unproductive because it doesn’t efficiently push blood throughout your penis. Jelqing with more than 75 percent is dangerous when you first start out because your penis isn’t conditioned for performing penis exercises.

To keep it safe, stay in the 40 to 75 percent range until you’ve been performing penis exercises for two months. After that, you can gradually increase your erection level and thus the amount of intensity.

Many penis exercisers find that jelqing at higher erection levels obtains more girth, whereas jelqing at lower erection levels obtains more length. Try different variations to see what works best for you. But never jelq with a 100 percent erection level. Your penis is resistant to change when it’s erect, and forcing anything on your erect penis is like forcing pressure on an inflated tire.”