An unconditional waiver is basically a waiver of all present and future legal rights. Such a waiver is most often utilized in the construction context by homeowners or professional construction companies wanting to protect themselves from mechanics' liens.
In most cases, a doctor who specializes in sports medicine will do a range of activities on a daily basis. Some of their most common patients are athletes, since sport injuries are very common and most athletic activities involve very forceful play.
A sports medicine physician is a doctor who specializes in taking care of people who have sports injuries. Sports injuries are injuries that people acquire from playing sports, exercising, or from otherwise being physically active. For example, when an athlete sprains their ankle during a game, they will go see a sports medicine physician.