My horse wants to rush the fences how can I collect and control that behavior?

A horse that rushes fences — that accelerates in the approach, flattens his stride, and arrives at the base of every jump at a pace that compromises the quality of the jump — is one of the most common jumping problems and one of the most mishandled, because the instinctive rider response to a rushing horse is to pull back on the reins, which creates exactly the cycle of restriction and acceleration that makes rushing worse rather than better. Rushing fences is almost always an anxiety response rather than enthusiasm or excess energy. The horse that rushes is typically worried about the fence and copes with that stress by accelerating through it rather than relaxing and maintaining rhythm. The rein contact that the rider applies in response adds restriction and backward pressure to an already anxious horse's experience, which increases his anxiety and therefore his rushing. This is why pulling on a rushing horse rarely produces a calmer approach. The training response that actually works addresses the anxiety rather than the speed. Trot poles and very small fences ridden at the trot are the most effective early tool because the trot gives the horse and rider more time to establish rhythm and relaxation in the approach. A horse that rushes small fences at the canter but can maintain rhythm at the trot over poles has told you the specific level at which the training needs to begin. The specific training exercise that most directly addresses rushing is the transition exercise — approaching a fence in canter, performing a downward transition to trot or walk a specific number of strides before the fence rather than jumping it, circling away, and approaching again. Repeated application teaches the horse that approaching a fence does not inevitably lead to jumping it. Once the horse consistently maintains his rhythm through these aborted approaches, the fence is reintroduced — but now the horse has learned to maintain his rhythm rather than accelerate. The rider's position and emotional state in the approach contribute more to rushing than most riders recognize. A rider who becomes tense, grips with the thigh, and closes her hands as the fence approaches communicates to the horse that something concerning is about to happen. Developing the ability to breathe deliberately, maintain a following seat, and keep soft following hands through the entire approach regardless of what the horse is doing is one of the most important skills for riders of rushing horses.