Which is the hardest endurance sport? Double-Olympic triathlon champ Alistair Brownlee has crunched the stats to find out

Double-Olympic triathlon champion Alistair Brownlee has recently undertaken an analysis of thousands of athlete training sessions to determine the "hardest" endurance sport. His findings, published via *road.cc*, indicate that cycling, perhaps surprisingly to some, ranks below sports like triathlon and running in terms of overall physiological demand and training load, based on metrics derived from his extensive dataset.

This statistical deep dive by Brownlee, a figure synonymous with extreme endurance, offers a fresh perspective on the perennial pub debate among athletes. While cycling's grueling demands are undeniable, particularly in Grand Tours, Brownlee's methodology likely accounts for the multi-disciplinary nature of triathlon and the higher impact forces and metabolic rates often associated with running. It challenges the common perception that pure cycling, with its long hours and high power outputs, is inherently the most taxing across the board.

Ultimately, Brownlee's data provides an interesting, if not definitive, answer. While every discipline presents its unique torments, perhaps the true 'hardest' sport remains the one you're currently trying to finish.