March 05, 2026

Physiological Profiling Explained - Why, How, and Important Training Implications for Triathletes

1 hour 8 minutes

Physiological profiling is often the missing link in amateur triathletes’ training programs. Knowing your profile on a scale from very endurance based (slow twitch phenotype) to very explosive (fast twitch phenotype) can help you avoid costly mistakes and break through plateaus in your triathlon training through better individualisation. In this episode, we discuss the ins and outs of this topic, from how to correctly profile an athlete without misinterpretation or overinterpretation, to important training implications for different athlete profiles.

HIGHLIGHTS AND KEY TOPICS:

What is physiological profiling?

Different methods, including race performance assessments, power-duration curve, Critical Power testing, psychological factors, and more…

What are the main differences between fast twitch dominant profiles and slow twitch dominant profiles, and why does it matter for your triathlon training program?

Training implications for different profiles: intensity, volume, session structures, nutrition, rest within and between sessions, fatiguability, and more

How to deal with different profiles in a group training setting

Practical takehome messages that you can use to improve your triathlon training.

DETAILED EPISODE SHOWNOTES:

We have detailed shownotes for all of our episodes. The shownotes are basically the podcast episode in written form, that you can read in 5-10 minutes. They are not transcriptions, but they are also not just surface-level overviews. They provide detailed insights and timestamps for each episode, and are great especially for later review, after you've already listened to an episode.

The shownotes for today's episode can be found at https://scientifictriathlon.com/tts687/

LINKS AND RESOURCES:

Muscle fiber types, recovery and training adaptations, and overreaching with Phil Bellinger, PhD | EP#297

Estimating Muscle Fiber-Type Composition in Elite Athletes: A Survey on Current Practices and Perceived Merit - Lievens et al. 2024

Muscle fiber typology is associated with the incidence of overreaching in response to overload training - Bellinger et al. 2020

WHAT SHOULD I LISTEN TO NEXT?

If you enjoyed this episode, I think you'll love the following related episodes:

Musculoskeletal adaptations, “train low” strategies, and muscle fiber types with prof. John Hawley | EP#248 - John Hawley is a legend in the field of exercise physiology, so if you’re somebody who wants to soak up all the triathlon science you can, this episode will be right up your alley!

Critical Power and VO2 kinetics with Mark Burnley, PhD | EP#257 - If you want to learn more about the science of Critical Power, and scientifically valid testing protocols, this is the episode to listen to.

You can find our full episode archives here, where you can filter for categories such as Training, Racing, Science & Physiology, Swimming, Cycling, Running etc.

You can also find separate archives for specific series of episodes I've done, specifically Q&A episodes, TTS Thursday episodes, and Beginner Tips episodes.

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By Mikael Eriksson

4.9

418418 ratings