I occasionally work 12+ hours with 80-90% of that time on my feet. On those days, I have to get my run in
before going to work, or it won't happen. For me that means super early mornings, but then I can go to work knowing that no matter what the day brings, I have completed my run. If I sleep in and don't run before work, it is much harder for me to find the energy after, and the run is slow and draggy. So my advice is get the run in while the world is still sleeping, then you can focus on other things (work, family, nap
) throughout the rest of the day.
You might get some better insights on this from JulieC (
http://juliec.fastrunningblog.com/). She is a nurse (plus a full-time mom) and works long shifts on her feet but still manages high mileage weeks.