Early triathlons were held as off-beat training exercises for runners. The first known swim/bike/run triathlons were held at San Diego’s (Calif.) Mission Bay in 1974. Organized by members of the San Diego, California’s Track Club, the events were held on summer evenings and were intended as no more than light-hearted breaks in the normal grind of training for marathons and 10Ks. This occurrence is well-documented and was not based on the French events. Amongst them were runners, swimmers and cyclists and before long training sessions turned into informal races. Directed and conceived by Jack Johnstone and Don Shanahan, the first Mission Bay Triathlon was held on September 25, 1974 and welcomed 46 athletes. This date is celebrated as the day modern triathlon began.
The first modern long-distance triathlon event (2.4-mile / 3.86-kilometer) swim, 112 mi (180.2 km) bike ride, and a 26.2 mi (42.2 km) run) was the Hawaiian Ironman Triathlon, know know as “KONA IRONMAN” which was conceived during the awards ceremony for the 1977 Oahu Perimeter Relay (a running race for 5-person teams). Among the participants were numerous representatives of both the Mid-Pacific Road Runners and the Waikiki Swim Club, whose members had long been debating which athletes were the greatest athletes: runners or swimmers. On this occasion, U.S. Navy Commander John Collins pointed out that a recent article in Sports Illustrated magazine had declared that Eddy Merckx, the great Belgian cyclist, had the highest recorded "maximum oxygen uptake" of any athlete ever measured, so perhaps cyclists were more fit than anyone. CDR Collins and his wife, Judy, had taken part in the triathlons staged in 1974 and 1975 by the San Diego Track Club in and around Mission Bay, California, as well as the Optimist Sports Fiesta Triathlon in Coronado, California in 1975. A number of the other military athletes in attendance were also familiar with the San Diego, California races, so they understood the concept when CDR Collins suggested that the debate should be settled through a race combining the three existing long-distance competitions already on the island: the Waikiki Roughwater Swim (2.4 mi./3.862 km), the Around-Oahu Bike Race (115 miles; originally a two-day event) and the Honolulu Marathon (26.219 mi./42.195 km). It was like nothing that no one present had ever done, they did not realize the bike race was a two-day, not one-day, event; CDR Collins calculated that, by shaving 3 miles off the course and riding counter-clockwise around the island, the bike leg could start at the finish of the Waikiki Rough Water and end at the Aloha Tower, the traditional start of the Honolulu Marathon. Prior to racing, each athlete received three sheets of paper listing a few rules and a course description. Handwritten on the last page was this exhortation:
“Swim 2.4 miles! Bike 112 miles! Run 26.2 miles! Brag for the rest of your life!”
— Commander Collins, (1978)
