Thanks for all your replies. I have just returned from a modest walk with Jazz, I was feeling awful for not taking him yesterday, although he did spend several hours "gardening" with me. Anyhow its not so warm today, with a nice fresh breeze so I decided to take him. I let him set the pace and he walked quite briskly, the route we took is fairly flat and I let him decide when he wanted to turn around. He is currently lying under the desk while I type this message and seems to be recovering fairly quickly. I am hoping and praying it is just the warm weather, and maybe the fact he also needs a hair cut.