There are so many benefits associated with cold water swimming for cardio health and fitness, and a lot of people, once they get used to the temperature and invest in an appropriate wetsuit, love to dive into a beautiful body of chilly water.

Whilst the mental and physical benefits of swimming in cold water have become much more well-known thanks to advocates like Wim Hof, it also provides a challenging environment for endurance swimmers, and cold water swimmers are amongst the fittest athletes around.

Whether they are the definitive fittest athletes in the world however led to a protracted debate that inspired one of the most famous and most challenging endurance events on the calendar.

The O’ahu Perimeter Argument

The island of Hawaii is an exceptionally important place in the history of many endurance events, having been one of the earliest adopters of the ultramarathon and similar long-distance events like the O’ahu Perimeter Relay, a 7-person 134-mile relay race.

In 1976, over 600 runners took part in the relay that even the best runners took over 12 hours to complete. However, the most historically important events that took place happened at the Primo Brewery afterwards.

With the blood and the beer pumping freely, the finishers, consisting of some of the fittest athletes in the world let alone on the island, started to talk about fitness, and specifically which athletic discipline was the toughest.

One of the teams, representing the Mid-Pacific Road Runners Club that had organised the Relay event in the first place, claimed that the sheer distance and unique levels of fitness you need for marathon and ultramarathon running means that the runners were best.

Meanwhile, the Waikiki Swim Club, known for the intense 2.4-mile Waikiki Roughwater Swim event, believed that swimmers, who used every muscle in their body as part of their discipline, were the fitter athletes, and soon a talk became a debate and then an argument.

At this point, John Collins, a Commander in the U.S. Navy and someone who had competed in the early San Diego Triathlons that took place in 1974 and 1975, chimed in, discussing how Eddy Merckx, the most successful road cyclist in history, has the highest aerobic capacity.

Aerobic capacity, often simply known as VO2 Max, is the maximum amount of oxygen your body absorbs and uses, and is an essential figure for endurance athletes.

He suggested that the best way to solve this debate was to have a multi-discipline race that combined the Honolulu Marathon, the Waikiki Roughwater Swim and the Around-Oahu Bike Race, now the Dick Evans Memorial Road Race.

He noted that anyone who could complete all three races in one day would truly be an “ironman”, which led to the athletes uproariously laughing.

However, John Collins was completely serious and devised a way to tweak the bike race so that its route would begin at the end of the Waikiki Roughwater course, and end at the start point of the Honolulu Marathon.

Fifteen men started the very first Ironman Triathlon event and twelve finished the race on 18th February 1978. The race has continued ever since, with tweaks made to the swimming leg to encourage safe swimming practices. 

Sarah A