She won the 90 km Comrades Marathon in South Africa in 2014, becoming the first British woman to win the race.

Greenwood is also a former champion and course record holder for the Canadian Death Race, Western States 100, and the JFK 50 Mile Run.

After graduating from university in 2001, she moved to Canada to work for a UK-based ski tour operator and has lived there ever since.

One off her first races was the 30-mile Knee Knackering North Shore Trail Run, a relatively short course known for its steep ascent and descent.

[2] There, after battling with the race leader, 2006 World Champion and compatriot Lizzy Hawker, she took gold in a time of 7:29:05, helping Great Britain to first place in the team event and also in the jointly held IAU 100 km European Championships.

[6] In 2012, Greenwood also broke the course record for the JFK 50 Mile Run, coming in 10th overall,[7] and was the winner of the Ultra-Trail du Mont-Blanc Courmayeur-Champex-Chamonix 101-km race.

[14] In the 2014 race, Greenwood took the lead at the 55 km mark and held on to it to win gold in 7:30:48, eight minutes ahead of second placed Chiyuki Mochizuki of Japan[15] and the third best time in the all-time list of British performances.