Injuries are an on-the-job hazard for distance runners. Training overload, the constant pounding over the highways and byways, can take its toll. A brilliant, course record-setting season-opening race at the Tracy Walters Invitational last September was a harbinger of state title promise for North Central’s Kai Wilmot. But muscular-skeletal injuries, including a stress fracture last spring, cost the junior talent virtually his entire cross country and track and field seasons.