The athlete that doesn't look gifted early often becomes the toughest competitor at the crux. Here's why pit bull phenotypes—strong, durable, mentally tenacious—need a completely different training approach than huskies or border collies. And why they often excel at HYROX before becoming elite endurance athletes.

High-volume training builds endurance. That's true. But loading it on an athlete who hasn't developed the aerobic fiber base to support it doesn't build fitness—it burns them out. Not because they weren't tough enough. Because the system was designed for a different phenotype

At 59, Mark Macgillivray finished 2nd male at the Saltire 24 — 167.8km covered, 2,468m climbed, one continuous day and night on his feet. Here's what his physiology testing predicted, and what actually happened when it mattered.

Feel explosive in the gym but flat on race day? You aren’t unfit—you’re inefficient. We explain why high-intensity training might be sabotaging your endurance, the science behind the "Run 2 Crash,"

We analysed four runners targeting a 3:30 marathon. Runner D had a massive "Ferrari" engine (VO2 Max 68), while Runner A had a modest "Sedan" engine (VO2 Max 48). Conventional wisdom says Runner D wins easily. The data proves the opposite. Find out why the "fittest" athlete on paper is actually the most likely to DNF.

Follow Nicole’s journey as testing helps her unlock the data, training insights, and confidence to take on Ironman Barcelona