They risk serious injury in every race - it has been calculated that an average jump jockeys will suffer a fall once every 10 rides.

In addition, most have to show unhealthily extreme self-discipline when it comes to weight.

Hours are spent in saunas and hot baths in an effort to shed crucial pounds, while eating a square meal is a rare luxury.

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Tony McCoy Richard Johnson Mick Fitzgerald Tony Dobbin Timmy Murphy Jim Culloty Ruby Walsh Norman Williamson Liam Cooper

There is also the travel factor - driving hundreds of miles each week to courses from Ayr to Exeter.

Because of the shared physical demands and risks, there is a strong cameraderie between jockeys.

Many drive to courses together, socialise together and go on holiday together - although on the racecourse, all are extremely competitive.

The top jockeys earn a good living but for most, it is not a lucrative profession.

They are paid a fixed rate of �103.25 for each ride.

In addition, they earn a percentage of any prize money won.

While this sounds like good money, many riders often only get a handful of rides a week, and often these are not on the best - ie prize money-winning - horses.

Many jockeys have "retainers" with a trainer, or sometimes with an owner.

This means they are paid a separate fee by that trainer/owner, who then has first call on their services.

Amateur riders

Most jockeys are professional but there are some amateurs, and some races which are restricted to amateurs - the most famous being the Foxhunters' Chase at the Cheltenham Festival.

Any amateur can be recognised on a racecard because he is always referred to as "Mr J Smith", whereas Richard Johnson's name would appear "R Johnson".

To help young jockeys get a foothold in the sport, those under 26 can claim a weight allowance in certain races (they are known as conditional jockeys).

They can claim 7lb until they have ridden 15 winners, then 5lb until they have won 35 races and 3lb until they have won 65 races.

There are female jump jockeys but few have enjoyed success at the highest level.