How to train a Derby winner

This weekend sees the most valuable and the most gruelling event in British flat racing - the Epsom Derby. Saturday's runners have been trained to the peak of their fitness to win £710,000 in prize money plus potential earnings of £10m at stud. But the science of training a winner is inexact and intuitive. "There are at least 100 different ways to train a horse for this race," says Simon Dow, vice-chairman of the Epsom Trainers Association, "There's no manual."

The Derby is for three-year-old colts only, and between the end of the two-year-olds' season and the start of Derby preparations these equine young teenagers mature into youths - and are changing rapidly, physically and emotionally.

If each horse needs individual treatment, there is at least a common rhythm. Over the winter, horses do little more than extremely gentle aerobic exercise, most of which consists of walking, much of it along roads. From the end of January, as soon as the weather permits, training begins in earnest with the routine punctuated by the recognised Derby trials at Chester, Lingfield and York.

While the exact training schedule varies from day to day depending on the temperament and condition of the horses, a typical gallops session is between 40 and 90 minutes during which a horse does two sets of 6.5 furlongs with a rest in between. Some trainers like to gallop their charges in single file, others run them two, three or even four abreast.

Improvements in the science of training horses have largely mirrored human experience. The emphasis is now firmly on quality, not quantity, with short, sharp sessions in which the horses will either canter, gallop and sprint in various combinations depending on their condition and where they are in their training cycle.

Just as human athletes rarely practise over the full length they intend to run, few horses will run the 12 furlong (one-and-a-half miles) Derby distance; most trainers run horses 400-metres short because it is at that point that the risk of injury dramatically increases.

The training sessions don't just get the horses fit, they help the callow three-year-olds get used to racing alongside others and learn to resist the desire to get in front. No horse has won the Derby in living memory by leading any further out than Tattenham corner, so the art of controlling and overtaking, which is key at Epsom, is honed on the gallops.

The trainer's art is to bring his horses to an extraordinary peak of muscle bulk and fitness at exactly the right time by giving them all the exercise they can endure. But diet is also crucial and in the run-up to the race, they are given as much oat-based feed as they can stomach, augmented by roughage like alfalfa and by electrolyte-rich mineral supplements.

Derby Day at Epsom remains the toughest test that any of the colts, many of whom have only raced once or twice, will have experienced. The opening four furlongs are all uphill and at a mile-and-a-half it's further than they've run before. It's also a left-handed track.

It is not usually the big horses or the stayers that do well, but fast, nimble creatures that can keep their balance on Epsom's horribly undulating track, especially when they hit the savage camber coming into the home straight. An unbalanced horse's first instinct is to put on the brakes.

Some trainers prepare for this by racing their horse on the undulating courses at Nottingham, Lingfield or Leopardstown. Opinion is divided on whether it's good to gallop at Epsom before the big day, but most top trainers prefer not to; they believe that a properly trained horse will rise to an unfamiliar challenge.

One of the most uncertain elements of that challenge is how a skittish young thoroughbred will behave when it suddenly finds itself in the presence of half-a-million tanked-up race-goers making more noise than it has yet encountered. ·