Buy yourself a 30 year old sled and use it.You'll be in great shape, just make sure it runs good so as to get you allot further from the truck.The continual breakdowns will provide a sort of therapy that only you will appreciate, you can expand your training by buying an ancient dirt bike, who the hell needs a mountain bike,you probably wished you had more time to yourself, problem solved. For every hour on the sled you have at least eight to walk back.Be warned,the faster the skidoo the greater the potential workout.Beginers should opt for a smaller snowmoble. Man I wish I had some discretionary income.