Andrew Schrauben

Triathlons are probably the most popular multi-sport event out there. I've never tried one, although I have completed a few adventure races. One thing that has intrigued me over the years is that most triathletes I know are cyclists who converted to triathlons, or for whom cycling is their strongest discipline. There are a few runners who dabble in triathlons but I don't know many swimmers gravitating to the sport.

Why? At first I assumed that the meticulousness required of cyclists to maintain their bikes is an attitude well-suited to triathlons - you have to keep lots of gear in order. Maybe this is why most adventure racers seem to hail from backgrounds in either mountain biking or rustic camping.

Seeking a better explanation, I started by comparing the lengths of disciplines involved with triathlons, specifically the iron-distance variety: 2.4 mile swim, 112 mile bike, 26.2 mile run. Is running a marathon equivalent to swimming less than a tenth of that distance? Let's examine a hypothetical situation...

Three buddies are training regularly for Ironman Hawaii. Each has a background as a single-sport athlete in each discipline. Sam is a Swimmer, Bob is a Biker, and Rick is a Runner. As a result, each is 10% faster than average in their specialty; in the other two disciplines they are average. In theory, they should each finish at the same time, right? Let's look at the results for the 2006 Ironman in Kona.

First up was the swim leg - average time was 1:16, which is when Bob and Rick came out of the water. Sam was 10% faster, so he finished at about 1:08.

Next was the bike leg - average time was 5:47, good for Sam and Rick. Bob's 10% advantage has him finishing in 5:12.

Finally the run leg - average time was 4:10, which is what Sam and Bob ran. Rick was 10% faster and finished in 3:45.

(We'll assume that all three of them were average in transition times at 4:30 per transition, 9 minutes total.)

You can probably see where this is going... Bob was the first of the buddies to finish, crossing the line at 10:47 and putting him 4.6% ahead of the average overall finishing time of 11:18. Rick finished 10 minutes later at 10:57, 3.1% above average overall. Then "straggled" in Sam at 11:14, his swimming prowess placing him just 0.6% above average overall.

No wonder most triathletes are primarily cyclists - they get the most bang for the buck! Swimmers get the shaft. For this reason some have proposed re-scaling the distances so that each discipline takes a similar amount of time, based on single-sport athletes' records for each. This has been called an "equilateral triathlon". For comparison, a traditional iron-distance swim/bike/run is 2.4/112.0/26.2 (in miles) while an "equilateral" iron-distance triathlon would sport distances of 7.5/60.0/26.2, where a world-class single-sport athlete could finish their respective discipline in just over 2 hours. Quite a difference!

However, is that really a fair comparison? What's more difficult: swimming 2 hours, cycling 2 hours, or running 2 hours? Maybe Sam's 10% swimming advantage only saves him 8 minutes of time, but also saves him proportionally more energy so that in theory he could do the next two legs a little above average, while Bob's 35 minute savings on the efficient bicycle doesn't gain him much extra energy over other racers.

Here's how I'd do it: Find out how many calories the average world-class marathoner burns over 26.2 miles. Then determine swimming and cycling distances where athletes of similar caliber would burn the same number of calories. That way competitors would strive for equal skill and efficiency among all disciplines in order to maximize their overall endurance. I believe that such an "energy distance" triathlon would be truly unbiased!