Shapecrunch insoles are designed as per your feet and biomechanics. Start by wearing them for no more than two hours the first day, and increase wear time by one hour each day after that. It may take from three to four weeks before you can wear them comfortably all day. Avoid running or other intense activities with the orthotics until your feet have had an opportunity to adjust to the new foot posture and you can wear them 8 hours a day. For runners, it is possible that some irritation may also develop in the arch, usually just behind the big toe. If you feel a “hotness” developing in this area take the orthotics out before a blister is formed. Lubricating this area may be helpful until the skin becomes toughened up. If you experience discomfort in your feet, ankles, knees or back while wearing your new orthotics, take them out of your shoes and reduce the wear time by one hour each day until the discomfort disappears.