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Sometime around the fall of 1974, Jack Johnstone and Dan Shanahan, avid runners and members of the San Diego Track Club, came up with an idea for a novelty race incorporating swimming, biking, and running. Admittedly, the pair didn’t put much thought into it: They scraped together a course, gave it a name (calling it a “triathlon” since swim-run events were already called biathlons) and posted the following message in their track club newsletter:
“The First Annual Mission Bay Triathlon, a race consisting of segments of running, bicycle riding, and swimming, will start at the causeway to Fiesta Island at 5:45 P.M. September 25. The event will consist of 6 miles of running (longest continuous stretch, 2.8 miles), 5 miles of bicycle riding (all at once), and 500 yards of swimming (longest continuous stretch, 250 yards). Approximately 2 miles of running will be barefoot on grass and sand. Each participant must bring his own bicycle. Awards will be presented to the first five finishers.”
The post drew the interest of 46 people, who paid a one dollar entry fee before gathering just before sunset on Fiesta Island, a swath of land centrally located in San Diego’s Mission Bay. The format was rather complicated: First, they ran a 3-mile loop. Then, they biked twice around Fiesta Island to cover five miles; then they swam to the mainland. Once there, they ran barefoot along the shore before swimming again, then hopped out for another run. And to throw an extra wrench in things, competitors had to crawl up a steep dirt bank before reaching the finish line.
Given the funky format and the late-in-the-day start, the first Mission Bay Triathlon was not without its hiccups. Some of the competitors– many of whom showed up with beach cruisers and three speeds–were still racing well after dark. Spectators brought their cars closer to the water with the headlights on so that people could see where they were going as they swam. Even race director Johnstone, who, like many other participants experienced that dreaded jelly-leg feeling from running off the bike for the first time, remarked, “As I dismounted my bike and tried to run, my legs felt like they didn’t belong to my body. I let out a moan of anguish and remember someone yelling to me, ‘well, it was your idea’.”
And a genius idea it was. The event caught buzz and triathlons started popping up throughout San Diego in the late 70s, but with the now ubiquitous swim-bike-run format. Four years later, in 1978, John and Judy Collins, who had raced the Mission Bay Triathlon prior to moving from California to Hawaii, dreamed up an even wilder event: A triathlon consisting of a, 2.4-mile ocean swim, 112-mile bike, and a 26.2 mile swim. “…whoever finishes first we’ll call him the Iron Man,” John is known to have said while planning the race, which had a humble start with just 15 entries (all male; the first woman competitor came along in 1979). When the Collins’ gave ABC’s Wide World of Sports the go-ahead to film the race in 1980, the footage landed in living rooms across the planet, and triathlon truly took off.
While triathlon, which attracts some 2 million people per year , now features multiple distances and formats, Johnstone and Shanahan will always be credited as the founding fathers of the sport.
Wrote Johnstone years later, and prior to his death in 2016 at the age of 80: “Now, I know, In this small way, along with Don, I changed the world; the course of athletic history.”