Plague of the overweight riders who are too heavy for their horses • Only one in 20 riders are within the optimum weight for their horse • A heavy load can mean back pain, lameness and bad behaviour in horses • Vet guidelines advise that riders weigh less than 10 per cent of their mount • Weighing more than 15 per cent of horse's weight poses health risks • Research is published in the Journal of Veterinary Behaviour Horses are the latest victims of the obesity crisis as they take the burden of their overweight riders, experts have warned. A...