Running Wild: inside the Ultra-Trail du Mont-Blanc (UTMB) race

Four British women take on the challenge of the famous Ultra-Trail du Mont-Blanc (UTMB) races in Chamonix, France. This short film by Seventwenty Productions follows Nikki Barnard, Milly Voice, Katy Dartford and Kaz Williams as they tackle the highs, and lows, of ultra-distance running.