How to Become an Ironman

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After competing in a few marathons and short triathlons, recreational athletes who crave something bigger often start dreaming about the next great challenge: An Ironman.

The grueling three-stage race pushes competitors to swim 2.4 miles and bike 112 miles before running a full marathon. The average finishing time for an Ironman race, according to RunTri.com, is 12 and a half hours, though some athletes stay on the course for as many as 17 hours.

Such an extreme physical endeavor may seem impossible. But with enough time, planning and dedication, experts say, most people can make it happen.

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“Anybody, if they have the desire, can definitely finish,” said Mark Allen, a six-time Hawaii Ironman world champion, head coach at MarkAllenOnline.com, and author of “Fit Soul, Fit Body: 9 Keys to a Healthier, Happier You.” “The biggest thing is taking time to slowly build up fitness and let the body adapt to training.”

That doesn’t mean it’s going to be pain-free.

“No matter who you are, even if you are a top professional, even me, when I started training every January, the first 30 or 40 minute run was tough, and I thought, ‘Gee, if that’s tough, how am I going to finish a marathon after the bike and swim,” Allen said.

“The distances seem out of the realm of possibility. But in Hawaii, people over 80 have finished, and people who are far from lean and mean have finished. You don’t have to be like a greyhound to finish an Ironman.”

For would-be competitors with no triathlon experience, Allen said, it can take up to three years to build enough fitness and triathlon experience to get to the starting line of an Ironman. Even athletes with a solid base in each sport should allow about a year to prepare.

As training progresses, the goal should be to do two weekly workouts in each sport, Allen said. One of those sessions should be for speed. The other should be for endurance with distances that grow by about 10 to 15 percent each week to a limit of about 4,000 yards in the pool, 100 miles or five and a half hours on the bike and two and a half hours of running. Tapering, or a gradual decline in distance, should begin about a month before race day.

Every other week, Allen added, it helps to practice the transition from biking to running because leg muscles that shorten up on the bike need to stretch out to run efficiently. Training for the changeover teaches the body to loosen up more quickly.

With a month to go, competitors should know what they’re going to wear throughout the race and how they’re going to handle the transitions between sports. Shorter races leading up to the main event are good opportunities to figure out the details and get out the kinks.