I would prefer you get more movement throughout the day versus doing cardio with weights (i.e. the sled). I think it's useful but I think spreading out is better because it keeps the joints moving over a longer time course vs sitting in a stationary position all day allowing the connective tissues to get stiff. I too hate doing a "conditioning workout" but I do walk my dog and hike and when I started doing that my knee tendonitis went away within a week and I don't have to force myself to do it. Find activities you both know you should do but also that you like to do. An high activity dog breed will force you into that if you care about the dog.