Laura Collett says vets have helped to explain why her top ride, Rayef, was so under par at the European Championships (news, 1 September).

Blood tests have shown that his muscle enzymes were “really high”, which indicates muscle soreness.

The gelding amassed three refusals on the cross-country course. Laura initially thought a virus might be to blame.

She told H&H: “We’ve had the vets checking everything. We think the soreness might have come from pulling a muscle on the course, or from catching himself on a fence.”

Although things did not go to plan for the youngest member of the senior British squad, Laura described the experience as “incredible”.

Rayef will be aimed at South of England later this month.

H&H vet Karen Coumbe added: “Muscle problems are well recognised in athletes, who can explain how uncomfortable they feel but it can be harder to identify in horses.”

This news story was first published in the current issue of Horse & Hound (15 September, 2011)