How To Convert Your 80/20 Triathlon Plan to a Duathlon Plan

by David Warden

A common question from our athletes is, “Can I use an 80/20 triathlon plan to train for a duathlon? Can’t I just cut out the swim workouts?”

It would be disingenuous for us to claim that our 80/20 triathlon plans are ideal for duathlon training. There are a number of differences in the specificity, run:bike ratios, and event distances between duathlon and triathlon training. There are also, however, some modifications that can be made to turn an 80/20 triathlon plan into an effective duathlon plan.

1. Pick an 80/20 triathlon plan that most closely matches your duathlon distance. Most duathlons are not triathlon-distance less the swim, but they are close. For example, the standard duathlon distance is a 10k run, 40k bike, and 5k run. The Olympic triathlon distance is the closest match to the standard duathlon distance.

2. Sure, cut out the swim workouts. Fortunately the 80/20 intensity ratios are calculated separately for the bike/run and swim. If you removed the swim altogether, the remaining bike and run workouts would still maintain 80 percent low and 20 percent moderate to high intensity. Consider that swimming is an excellent cross-train and recovery activity, and you might actually benefit from completing the bulk of those scheduled swim workouts.

3. Round up the total weekly run training to the next full hour. For example, if your total scheduled run training for the week was 2.5 hours, add 30 minutes of running to make it an even 3 hours for the week. This aligns the total run:bike ratios closer to actual duathlon distances. Of course, you’ll want to ensure that the extra running time you add is close to 80/20 intensity to maintain the total weekly intensity balance.

4. When using the 80/20 70.3 and IM plans, perform 30 minutes of the run portion of long week-end brick workouts before the bike, making your long brick a run-bike-run workout. Conveniently, the 80/20 Sprint and Olympic plans already utilize a run-bike-run format, which will provide excellent specificity to your short course duathlon training.

Despite the necessary modifications, is it likely that these modifications to an 80/20 triathlon plan will provide superior results to a 3rd-party duathlon plan that does not use the 80/20 system.