The amount of tension produced by any method must be adjusted to avoid causing injury, pain, or discomfort, and provides a limit on the rate at which new skin can be grown. There is a risk of seriously damaging tissues through the use of excessive tension or applying tension for too long. Websites about foreskin restoration vary in their recommendations, from suggesting a regimen of moderate amounts of tension applied for several hours a day, to recommending periods of higher tension applied for only a few minutes per day, as with manual techniques.