Here’s What You Need to Know About Every Triathlon Distance

As you dip your toe into the triathlon, it might be overwhelming to choose a distance. Your coworker could be yammering on about his half Ironman, while you just want to try a multisport activity. 

The good news is no matter your goal or experience level, the triathlon can be made to fit your specific needs.

“You don’t have to do anything,” explains Jonathan Cane, a New York-based exercise physiologist, and running and triathlon coach. “Runners think they have to do a marathon to be validated as a runner. But don’t get fixated on longer distances unless it’s something you want to do.”

Whether you want to focus on short distances or work your way up to a half Ironman or Ironman, Cane, co-author of Triathlon Anatomy, says to start short.

“I’d rather my athletes be really good at a sprint or an Olympic distance than survive a half Ironman or Ironman,” he says, noting that for the time-strapped athlete, shorter distances require less training. 

Here are the most common triathlon distances and how best to approach each one. 

Sprint Triathlon Distance

Sprint triathlons are a popular distance for athletes who have been eyeing the sport. But, Cane says, there are plenty of professional triathletes who focus only on these distances—just like there are world-class 5K runners who never touch the marathon. 

The standard sprint triathlon distance includes a 750-meter swim (so, just under a half-mile), a 20K ride (12.5 miles), and a 5K run (3.1 miles, for you non-5Kers out there). 

Many race directors, however, take liberties with the sprint distance, often because the athletes don’t particularly care about the exact distance. For example, first-timers who are most apprehensive about the swim, might look for a triathlon that has just a 1/4-mile swim. 

“There’s something freeing about doing an odd or unconventional distance because you’re not getting wrapped up in time, trying to beat a previous result or your friends,” Cane says. 

Sprint triathlons are also very manageable when it comes to training if you work full-time or have a family, with two workouts per discipline, per week. Cane recommends setting aside an hour a day during the week and about 90 minutes to two hours on the weekends for longer workouts. 

Olympic Triathlon Distance

As dictated by its name, the Olympic triathlon distance is what takes place during the Olympic Games. It’s slightly longer than a standard sprint: 1.5K swim (just under one mile), 40K bike ride (25 miles), and a 10K run (6.2 miles). 

Training and race day, Cane says, won’t look much different from a sprint distance. Athletes will still target two workouts per discipline per week, but each one will be slightly longer. In some cases, and this goes across distances, athletes might benefit from adding an extra workout to their weakest discipline—often swimming. 

Half Ironman Triathlon Distance 

For the seasoned triathlete, the half is a formidable challenge that still allows for some time between work, home life, and training. A half Ironman challenges its athletes to a 1.2-mile swim, 56-mile ride, and a half marathon (13.1 miles)—or, as the bumper sticker says: 70.3. 

Once you commit to a half Ironman, you’ll start to see double workouts, with three workouts per discipline per week. Cane offers up this schedule as an example: Monday and Wednesday with single workouts, Tuesday and Thursday with double workouts—like a swim and a run—Friday as a rest day, and long rides and runs over the weekend, including the notorious brick workouts—two workouts done back to back. 

For the ride and swim, Cane says, athletes will touch on race distance, but might run a little less than a half marathon. Running, of course, takes a much greater toll on the body. He recommends athletes set aside 60 to 90 minutes for weekday workouts, two to three hours for weekend rides, and one to two hours for a weekend run. 

Ironman Triathlon Distance 

When you see a 140.6 bumper sticker you know that person has completed the behemoth of the triathlon distances: the Ironman. (Okay, Cane notes that in recent years, there’s been growth in “ultra” triathlons—distances longer than 140.6.) 

The Ironman comprises a 2.4-mile swim, 112-mile ride, and a marathon (26.2) miles. 

It’s not for the faint of heart, and Cane highly recommends triathletes spend a good amount of time in the sport before attempting this distance if that’s on their bucket list. 

“Don’t rush into long races,” says Paul Capuzzo, a New Jersey-based triathlete who’s been racing for triathlons nearly 20 years. “Resist the peer pressure to sign up for a 140.6 until you have some years of training and racing under your belt.” 

Training for an Ironman doesn’t leave room for much else, with three workouts per discipline per week, each for about two hours during the week and about four to six hours on the weekends. 

“You don’t take a marathon training program and plug it into an Ironman program, with multiple 20-mile runs,” Cane says. “But you’ll bike for several hours and then run 13 to 14 miles.” 

Types of Triathlons 

While there are a variety of triathlon distances, the sport itself is fairly well defined. Athletes will compete in open water—a lake, pond, or ocean—and bike and run on a road. But, Cane says, the triathlon community is starting to see slight tweaks to the traditional race, including pool swims, trail rides and runs, and gravel rides. 

“Pool swims are such a great introduction to the sport,” he says, noting that some newer athletes might opt for a longer distance in a pool or lake because an ocean swim is much more intimidating. 

While Cane doesn’t recommend a mountain ride for novice triathletes, he says the new style of triathlon might be appealing to an accomplished mountain biker who wants to try something different. 

There are tweaks to a typical triathlon, too, for those who are exploring multi-sport activities: 

Duathlon

Often confused with the biathlon, which is the Olympic sport of shooting and skiing, a duathlon is a triathlon minus the swim. Athletes run, ride, and run again over a variety of distances. According to the Team USA website, distances range from a competition that includes a 1-mile run, 5-mile ride, and 1-mile run to an 18-mile run, 62-mile ride, and 18-mile run—with everything in between. 

Aquabike

While the aquabike event sounds like you ride a bike in the water, it’s actually a multi-sport event that includes swimming and road biking, a favorite among strong swimmers who dislike or are injury-prone to running. Distances range from a competition that includes a quarter-mile swim and 5-mile ride to a 2-mile swim and 62-mile ride. 

Relay

A relay triathlon event can be the best of all worlds, whether you’re an avid runner who doesn’t know how to swim or an accomplished swimmer who wants to try your leg at running. Local triathlon events often offer a relay option, which allows a three-person team to tackle each leg: swim, bike, run. 

Only one athlete per team can be on the course at a given time, and during the transition period, athletes will hand off the timing chip for the next leg. 

A local relay triathlon is much different than the mixed team relays, which comprises teams of men and women. Each athlete must complete a mini triathlon in its entirety—a 300-meter swim, 6.6K ride, and 1K run before the next athlete completes, alternating between female and male. 

Triathlon Divisions

Like cycling and running competitions, triathlon events include age group divisions, for which athletes can compete for division awards. In an effort to make the triathlon more inclusive, event organizers started Clydesdale and Athena divisions based on minimum weight requirements. 

The Clydesdale division is for men who weigh at least 220 pounds, and the Athena division is for women who weigh at least 165 pounds. 

In 2014, the USAT announced its inaugural Clydesdale and Athena Nationals competition. 

“These competitors are passionate about the sport and about their competitive division, and we felt it was time to recognize that with a standalone National Championship event,” said Tim Yount, USA Triathlon chief operating officer, in a 2014 statement. “We have seen an influx of participants in these divisions in recent years and with national titles on the line at two race distances, we expect that we will see this area continue to grow.”

Choosing a Triathlon Distance 

At the end of the day, Cane (and arguably the majority of coaches) want athletes, especially newer ones, to have a memorable race experience that will keep them in the sport for life, and of course, to avoid injury.

“If you take someone and throw them into an intimidating race unprepared or underprepared, their introduction to triathlon is going to be a negative one,” Cane says. 

The better way, he says, is to start short and progress into longer distances, if that’s the goal. 

Heather Mayer Irvine is a freelance journalist based in Pennsylvania. She is the former nutrition and training editor for Runner’s World and the author of the Runner’s World Vegetarian Cookbook (2018). Her work has appeared in Runner’s World, Bicycling, Popular Mechanics, The Boston Globe, Cooking Light, CNN, Glamour, and The Associated Press. She’s a seven-time marathoner with a personal best of 3:31 but is most proud of her 1:32 half marathon, 19:44 5K, and 5:33 mile. She’s done one sprint triathlon and is terrified of open water.