Watch: Lizzie Kelly takes on Rugby World Cup winner Rachael Burford

Sporting worlds collide as two-time Grade 1-winning jockey Lizzie Kelly went head-to-head with Harlequins Ladies captain Rachael Burford in a series of fitness challenges to determine which sport reigns supreme.

The pair squared off in four physically-demanding contests of planking, highest vertical jump, cycling and riding an equiciser.

Kelly became the first female jockey to win a Grade 1 race over jumps when Tea For Two won the Kauto Star Novices' Chase at Kempton in December 2015, while Burford was a member of the England squad that won the Women's Rugby World Cup in 2014.

Find out who came out on top in the video below:

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