What do the following numbers have in common: 140.6, 70.3, 30.9, and 15.5? They all represent the various distances of one of the most exciting and demanding sports — triathlon. As a triathlete and doctor of physical therapy, this is one of my passions and has provided many benefits both physically and psychologically. Triathlon has been gaining enormous popularity worldwide since 1978, when 15 amateur athletes, including one woman, set out to conquer a distance of 140.6 miles by swimming 2.4 miles, biking 112, and finishing it off with a 26.2-mile marathon, all in one day. The race has been the brain-child of a Navy Commander John Collins and is widely considered one of the most difficult one-day endurance sporting events in the world.