Dog agility. Here in the far north we suffer from months of ice and deep snow. Training outside brings on a host of injuries. Started doing dog agility on a whim for entertainment one night a week. I can work them for 20 minutes and have their tongues hanging out. Made them better hunters and to be honest I have a lot of fun doing it. Basically the dog is doing wind sprints in the dirt, also requires me to exercise. Come spring we do an agility session and than go throw bumpers in the field.