Coach Delphin: "Nothing in HYROX is extremely heavy on its own — it feels heavy because you're fatigued"
Delphin is a HYROX, triathlon and running coach from the Netherlands, a pro athlete himself, a veteran, and gym owner at De BlakMad. His answers go deeper into the technical side of HYROX preparation than most — real periodization, real pacing data, and a clear-eyed view of what athletes consistently get wrong.
A weekly structure in terms of intensity, zones, and strength distribution depends on the phase of your periodization. In the early phase, duration is more important than intensity. More Zone 2 sessions are key to building your aerobic engine. From a conditioning standpoint, the focus is on extensive intervals, steady-state runs, and longer HYROX endurance sessions — controlled SkiErg and Row work.
In strength training, the emphasis is on compound movements, often using supersets to increase total repetitions and muscular endurance. There should also be one high-intensity HYROX mixed session included each week. In this foundational phase, improving technique across all HYROX movements is essential.
As race day approaches, these sessions gradually shift toward more specific work and higher intensity to match competition demands.
If running times aren't getting faster but instead slower, that's generally a major red flag. HYROX is about strength endurance, with the primary emphasis on endurance — not maximal strength. What often stands out is that athletes who train with schemes like 3 sets of 10 reps or 4 sets of 8 reps tend to struggle during a HYROX race. Nothing in HYROX is extremely heavy on its own; it feels heavy because you're fatigued and still required to produce force.
This really depends on the phase of periodization. In block 1, this ratio is clearly different from block 2 or block 3, for example if you are preparing for a race over a 12-week period. In the beginning, the ratio between easy work and hard work is really something like 80/20. But this does change as we get closer to the race.
My experienced athletes are allowed to start hard on kilometer 1. This is the only run that does not have to be performed under fatigue. During and after the SkiErg, the racing and pacing really begin. At that point, they simply need to know the paces they are capable of running. You get this from data — for example from a half HYROX you have completed in training.
Keep in mind that during the race you can often add 10 to 15 seconds on top of that pace. Running zigzag laps in an indoor venue costs more energy than when you trained outside or on a treadmill.
There aren't really strict benchmarks. There is no time cap for completing a HYROX. I do always say that you should be able to run 16 km continuously for a good solo race and 12 km for a doubles race.
In addition, for a solo, you must be able to perform all exercises smoothly and with proper technique. Beyond that, time is simply pressure people put on themselves. But finishing is always possible if you have done the things mentioned above.
I would structure it as follows. Of course, this would change again as you get closer to the race. But this could be the base:
- Monday: Mixed workout with a combination of strength and conditioning
- Tuesday: Interval running
- Thursday: HYROX-specific endurance session or longer conditioning workout
- Saturday: Long endurance run