What is a triathlon?

Three races in one: swim, bike, run.

As staed in wikipedia's entry, "A triathlon is an athletic event made up of three contests (from the Greek). In contemporary usage, the name triathlon is mostly applied to a combination of swimming, cycling and running, in that order. In most modern triathlons, these events are placed back-to-back in immediate sequence and a competitor's official time includes the time required to "transition" between the individual legs of the race, including any time necessary for changing clothes and shoes. As a result, proficiency in swimming, running, and cycling alone is not sufficient to guarantee a triathlete a competitive time: trained triathletes have learned to race each stage in a way that preserves their energy and endurance for subsequent stages."