New research suggests a properly fitting helmet greatly reduces the severity of head injury. Joe Torg, an orthopedic surgeon at Temple, said helmets should be checked weekly to ensure the lining is properly inflated. "It is not uncommon for the (helmets') air bladders to lose pressure," causing them to fit improperly. Paul Kelley, athletic equipment supervisor at Temple, said student athletes of all ages should be fitted for a helmet by a coach or someone else trained in fitting techniques.