Ironman: Run a Marathon? #2

I received the following question from an athlete today.

Q: I just finished reading a blog you had on your website from December 2008 with your advice against doing a marathon as preparation for an Ironman race. I have a follow-up question.

This is my second year doing triathlons, and I am currently doing Half Ironman distance races as my A races. I contemplated signing up for an Ironman in 2010 but have been told by another athlete, whom I respect and has been doing triathlons for over 12 years, that I should do a marathon before signing up for an Ironman. My friend suggested waiting until 2011 to do an Ironman.

For 2010, I again plan on choosing Half Ironman distance races as my A races. My first A race will be Wildflower Long Course in early May 2010. I would like to do a flat marathon in late January 2010. This would be my first marathon, and it would be a great accomplishment for me. Do you think doing the marathon would inhibit my training for Wildflower?

A: By all means, if you want to run a marathon do it. The biggest risk is that you will become injured with a lot of running and lose some training time before Wildflower. There is also the issue of how serious you get about your time for the marathon. I'd recommend keeping your finish time low key and continuing to bike and swim pretty much as you normally would for a half Ironman. Just increase your longest weekly run and aim only for finishing the marathon.

The other issue you bring up here is if the marathon training will benefit an Ironman. My point in that blog was that training for a fast marathon is likely not to be beneficial. If you've never run 26.2 miles before doing a marathon may help with the mental issues, especially if you just run it slow and easy. But physiologically speaking, running for a fast marathon time and running the final leg of an Ironman are otherwise not similar. Your pace in an Ironman run will be very slow by your marathon racing standards. The training to race a marathon would be greatly different also. That is not the way you train for an Ironman run. Then there are the issues of time spent training for a marathon in regards to swim and bike training time (cycling for most is really the critical sport in an Ironman), and also the time needed to recover from a marathon with an upcoming Ironman. And finally, as mentioned, the risk of injury is high when training for a serious marathon.

Your friend may run marathons and believe it is making him better for the Ironman. Who knows, it may be doing that some how. There are a lot of variables when it comes to sports performance. I also know of athletes who hardly run at all and still do very well. In the last few years two pros broke 3 hours in their Ironman run splits running less than 20 miles per week. One did a single long run of 12 miles, yet he still broke 3 hours and won an Ironman. It worked, but I wouldn't recommend this either.

I also agree with your friend that is best to delay the Ironman until 2011. But I'd suggest that simply because you are so new to the sport. You need more experience before attempting a full Ironman. Instead, as you seem to be suggesting, do several races in 2010 including a couple of half Ironman races. But realize that a half Ironman is more like a 'double Olympic-distance' than half of an Ironman. Ironman is in a category all by itself.