This is a subject close to my heart as a keen horse rider i regularly encounter dog walkers. Unfortunately i do frequently come across dogs who are totally out of control which put both them, myself and my horse at risk.
Horses are prey animals so their natural instinct is to run away from anything they perceive as dangerous. This flight response can be triggered by a dog barking, lunging on a lead or even approaching them suddenly. By teaching our dogs to act calmly we are acting responsibly and ensuring our dog does not put either horse or rider in danger.
The first thing to do when you see a horse and rider is to put your dog on the lead and gain their attention. Natural Instinct chicken hearts or liver treats are ideal as they are high rewards. Then position yourself to one side of the pathway ensuring the rider has maximum room to pass you.
Focus your dogs attention on you in a calm fashion positioning him so he is facing away from the horse
Ensure the rider has passed before rewarding the dog and walking off. Make sure he is a safe distance away before allowing your dog off lead.