"You can motivate by fear, and you can motivate by reward. But both those methods are only temporary. The only lasting thing is self motivation." -- Homer Rice, football coach
Tim Morrill and Melissa Witmer make use of videos to explain how to build fitness for ultimate. They are both professional fitness trainers and ultimate players, who have investigated how to improve your conditioning specifically for ultimate. I haven't seen many others who can claim all three of these things, and are sharing their stuff with the world.