In Britain, the minimum riding weight is 8st 0lb for Flat jockeys and 10st 0lb for National Hunt jockeys, although apprentice or conditional jockeys can claim a 7lb allowance, which reduces the minimum riding weight to 7st 7lb and 9st 7lb, respectively. Consequently, while there are no rules or regulations regarding height, most male jockeys riding on the Flat in Britain are significantly shorter than average height – that is, 5’10” – simply because taller riders struggle to meet the weight requirements.
According to reigning champion trainer John Gosden, Lanfranco ‘Frankie’ Dettori, who stands 5’3” tall and can ride at 8st 6lb, or 8st 7lb, is ‘perfectly proportioned’ for a jockey. Indeed, Dettori is just an inch taller than the average Flat jockey and, although 5lb or 6lb heavier than average – after all, he is 48 years old and entering the twilight years of his career – Gosden was keen to point out the importance of a suitable physique and strength-to-weight ratio in any jockey. Generally speaking, Flat jockeys typically stand between 4’10” and 5’6” tall and weigh in between 7st 10lb and 8st 6lb – or, in other words, 5’2” and 8st 1lb, respectively, on average – but also need to be extremely fit, with an abundance of core, leg and shoulder strength.