Courtney Dauwalter: Step inside the 'pain cave', where rules are remade - BBC Sport

Courtney Dauwalter used to teach biology. Now her ultrarunning achievements are challenging centuries-old ideas about the differences in physical capabilities between men and women.

1 day agoShareclose panelShare pageCopy linkAbout sharingBy Olivier GuiberteauBBC SportImage source, Getty ImagesImage caption, Dauwalter has won the women's race in three of the last four stagings of the Ultra-Trail du Mont-Blanc.

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Chamonix is rocking. A voracious melee of thousands squeeze into the French town's narrow streets to witness the culmination of a true monster - the 106-mile (170km) race known as Ultra Trail du Mont Blanc.

Crossing three international borders while circling the tallest mountain in Europe, UTMB is widely regarded as one of the most competitive ultra-marathons on the planet. Combining a carnival atmosphere with a total elevation gain of 10,040 metres - more than 1,000 metres higher than Mount Everest - it is a bruising, bashing, blow-out of a weekend - and this one is particularly special.

UTMB: Up close and personal at the world's biggest, wildest trail race

https://www.bbc.co.uk/sport/athletics/67945344?at_medium=RSS&at_campaign=KARANGA

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