I've been rollerblading for 30 years. I firmly ask that you do not try this at home. For me, its one of the best conditioning tools that you can use. The reason is that you can FEEL how strong the dog is. Day 1, I rollerblade along with him, day two, I let him pull until I feel him pulling less. When I feel he is not pulling so hard, then I rollerblade alongside him...never letting him come to a complete stop. Day 3, I rollerblade alongside him. Day 4 I rest him completely. The trick is to get to the point that on the second day he pulls hard non-stop. Then you know he has the strength built up in him. At the end you taper it down. The treadmill doesn't tell you when the dog is tired, neither does the cat-mill, but on BLADES... you can FEEL it. This is a 10 Week process. Anyway, It started to rain and it was too slippery, not to mention I was recording with the right hand while the left hand was holding on to Machobear. Again, do not try this at home.