Found on Ironman.com and written by Jennifer Ward Barber
Next time someone tries to call it “just a half,” here’s a list of reasons why IRONMAN 70.3 is the new … black.
A week ago I ticked my seventh IRONMAN 70.3 race off the list. Crossing the finish line in Austin, Texas, besides the sense of personal achievement, got me thinking about the uniqueness of the distance. With seven in the books, I’ve grown to love the distance. And, despite the discomfort of racing—the kind that makes you swear you’ll never do this again—24 hours later I was strategizing about what 70.3’s I want to do next year.
Nestled between the fast, dynamic Olympic-distance racing and the venerable IRONMAN, the 70.3 occupies a unique place on the distance spectrum. Here are seven reasons to love it:
1) The IRONMAN 70.3 is a friendly distance. It’s a challenging step up from shorter-distance races (sprints and Olympic/international) to “test” yourself at a longer, more endurance-focused event. Once you complete one, you’ll probably know whether you’re hooked, or whether you’re more suited to training and racing shorter events. If you’ve only done short races, a 70.3 is a significant feat to tackle, and one worthy of respect. On the flip side, the distance is also a reasonable (I hesitate to say “easy”) step down from IRONMAN. If you’re an athlete who jumped straight into the full distance, the half distance provides a taste of speedy, peppy racing that can be addictive in its own right. Once you’ve completed a few IRONMAN races, maintaining the fitness to do a 70.3 is a no-brainer. 
2) Whatever way you slice is, training for a 70.3 is simply more reasonable than training for an IRONMAN. In as little as seven to 10 hours a week, a new triathlete can become fit enough to complete a 70.3, as compared to the 15 to 20 hours most experts recommend for IRONMAN.
3) Many people’s first IRONMAN goal is simply to finish. For more seasoned triathletes, the IRONMAN 70.3 distance offers the chance to focus more on performance (qualifying, setting PR’s, etc) than just getting across the finish line.
4) IRONMAN 70.3 events are more spectator-friendly and facilitate more race-day fun. Most athletes complete the race between five and six-and-a-half hours, and the race is over in the afternoon, rather than the dinner hour. This leaves the evening open for celebration and unwinding. As a destination race, 70.3’s leave more time and energy in the tank for sightseeing.
5) As a logistical trial run for IRONMAN, the 70.3 is unparalleled. Planning and preparing race bags, executing a nutrition plan and dialing in things like bike fit and gear choices can be executed with less risk than in a full IRONMAN.
6) There are a huge variety of races to choose from in many easily-accessible locales. Registration for IRONMAN 70.3 events usually doesn’t fill immediately (with a few exceptions), making last-minute race decisions easier.
7) With a few exceptions, these events usually feature wave starts, an appealing feature for new triathletes wary of the mass start.
A bonus “.3” reason to do an IRONMAN 70.3? The more you do, the fewer running shirts you’ll need to buy. I now have one for every day of the week.