Endurance Essentials

Endurance Essentials

Mid-Pack 70.3 Triathlon Training

The Core Program

Gordo Byrn's avatar
Gordo Byrn
Aug 04, 2025
∙ Paid
From the archives. Racing Vineman 70.3 in July 2000 (!). My first time qualifying for Ironman Hawaii. 3rd in the M30-34 with a 4:16:49.

The most important thing to remember is you are training for a 70.3 triathlon, not

  • A 2 km swim TT

  • A 90 km bike TT

  • A Half Marathon

Training, and race pacing, is aimed at the totality of your event.

With respect to the totality, let’s start by getting a feel for the average duration you’re going to be out there.

Grok came up with a range of 6 to 6.5 hours for the median finisher. You can find the whole thread here.

The breakdown is helpful for guiding training…

We are getting ready to COMBINE a 40 minute swim, a 3 hour bike and a 2 hour run.

To have our best race day, we need to place our greatest effort into the run.

  1. Relaxed swim

  2. Catered bike ride, then

  3. An endurance run building to a Tempo finish.

Race pacing for the mid-pack athlete:

  • Swim - easier than 6 hour pacing.

  • Bike - no more intense than 6-hour pacing.

  • Run - hopefully, faster than 6-hour pacing.

For the mid-pack athlete, 70.3 training is all about Endurance & Strength.

You do not need a VO2 Block or sustained Red Zone efforts.


You do need to direct your energy into making a six-hour training day as routine as possible.


Key Workouts

As a 70.3 athlete, you have an advantage over athletes training for Ironmans and marathons.

You can routinely train for your race duration and distance.

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