Switching From Triathlons to Marathons

BY Hal Higdon

A program that features three days of running a week, but with two days of cross-training would keep you connected to your triathlon roots, while providing the proper volume of running that would prepare you for a marathon. 

Have a question about running? You’re in the right place. Every Tuesday, world-renowned coach, author and athlete Hal Higdon posts and answers athlete questions here. You can submit your question by joining the discussions on Hal Higdon’s Virtual Training Bulletin Boards.


I am an experienced triathlete and coach of triathletes, but my goal is to crack 3 hours in the Barcelona Marathon in March. I have run 1:18:20 for the half marathon; my fastest full marathon at the end of an Ironman Triathlon is 4:07. Runners come to me all the time for help in making the switch from the marathon to the triathlon. I am quite happy to ask a running coach to help me going the other direction. Give me a plan.


Like the waitress says in the high-price restaurant after you place your order, “Good choice.” I congratulate you in seeking expertise beyond your own obvious knowledge. Your fast half time more than predicts a sub-three performance, but why not do it right? The best advice I can offer you consists of a single word: Specialize!

A long, long time ago in a distant galaxy, when triathlons had just begun to achieve popularity, I competed in tris at various distances with some success. My running ability allowed me to catch and pass a lot of better swimmers and cyclists on the third leg. I qualified for the Ironman World Championships one year, but didn’t go to Hawaii because I felt I was unprepared, both physically and psychologically, for the extra distance, particularly 2.4 miles in the Ocean. Whew!

My hat is off to all those capable of such feats. While training in all three events, I did notice that over a period of years, as I improved as a swimmer and cyclist, I declined as a runner. It was a trade-off, the law of specificity. If you want to be a good triathlete, you need to balance your training for three sports. If you want to be a good marathoner, you need to focus your energy on one, allowing those other two sports to drift out of your life-at least until you finish the marathon.

Having said that, the best advice I can offer is to forget you are a triathlon coach for 18 weeks leading up into your marathon. In that respect, almost any of my programs could work for you. Novice 2 might be kindest. Given your previous success as a runner, you might be able to handle one of my Intermediate or Advanced programs, although at some risk. Your body will not yet be tuned up for that much running. You could get in trouble if you pile on too many miles too soon.

That being the case, you might be more comfortable picking a program somewhere between the triathlon and the marathon. Buzz over to my website and check out my Marathon 3 program. It is an 18-week program that features three days of running a week, but with two days of cross-training. That would keep you connected to your triathlon roots while providing the proper volume of running that would prepare you for a sub-three marathon. Pick whichever of the other two sports you want to fit into those two days. For example, your workout on your cross-training day could be a half hour on the bike, then dive into the pool for a relaxing swim. I know you can do it. Good luck.

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The Ultimate Full-Distance Training Guide

Training Guide

This guide is designed to be used as you train for a full-distance triathlon, with in-depth information on every part of the process. Each chapter is packed with tips, workouts, and insights from triathlon coaches, to give you all the tools you need to succeed.

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About Hal Higdon

Hal Higdon is a Contributing Editor for ‘Runner’s World‘ and author of 34 books, including the best-selling ‘Marathon: The Ultimate Training Guide’. He ran eight times in the Olympic Trials and won four world masters championships. Higdon estimates that over a quarter of a million runners have finished marathons using his training programs, and he also offers additional interactive programs at all distances through TrainingPeaks. Hal uses TrainingPeaks to power his interactive marathon and half marathon training plans — check out more of Hal Higdon’s training plans on his website.