In road running, VO2max, lactate threshold, and running economy can explain up to 95% of the variation in performance between athletes. In trail running, that same model barely holds together, with running economy being the worst predictor of the three.
In this episode, Dr. Simon de Waal walks through his research journey trying to work out why. From his systematic review of the existing evidence, to a full pacing analysis of Ultra Trail Cape Town using Strava data and treadmill testing at steep gradients. Along the way we cover velocity at VO2 max as a hidden composite metric, why uphill-specific testing changes the picture, why downhill collapse is the clearest sign of mechanical fatigue late in a race, and why prior race results still beat most lab tests.
It's a comprehensive look at just how multifactorial trail performance really is, and why researchers are still working out how to measure it properly.
Dr Simon de Waal grew up running trails around Cape Town before turning it into a research career. He completed his PhD at Stellenbosch University under cycling physiologist Robert Lambert, and now researches trail running performance at the University of Gloucestershire while coaching through Rooted in Dirt.
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Follow Dr. Simon De Waal
Work with Dr. De Waal at https://www.glos.ac.uk/staff/profile/simon-de-waal/ or by contacting him at sdewaal[at]glos.ac.uk
Looking to get coached by Dr. De Waal? Find him at https://rootedindirt.com/ and https://www.instagram.com/rootedindirt/
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