Tim Graham, charted his exercise and associated physical pains from February to June of 2008. I'm not sure if it yielded anything of use for him but it's an interesting "exercise" in data visualization.
It may not be all that interesting in and of itself but I do think it is part of a larger, growing trend that involves data capture and display. I will be posting some longer essays on this subject in the near future.
I made a quick video capture of the animated data. See below.