Rolling Start

A rolling start is most commonly used in triathlon, a rolling swim start has athletes start their race in separate groups, generally organized by predicted swim time. This keeps swimmers of similar capabilities closer together and avoids some of the chaos often witnessed in mass swim starts. On the other hand, age group swim starts – which are now standard in Ironman championship races – have athletes start their swim based on their assigned age group, not their predicted swim time. In running, a rolling start would be the equivalent to a wave or corral start.