Triathlons and Multisport Races are popular fitness challenges. Multisport races can be swim-run, or other combinations. Some multi events have paddling, cycling and other combinations. The Olympic Games includes the Modern Pentathlon with five events (swim, run, laser pistol, fencing and horse riding). Aqua bike races are swimming and cycling, but the running is not done.
ISCA's partner, Tri Coach Academy, has many resources.