I go twice a day cos i take my dog who's pretty hyper and needs to run twice a day. In the morning i go to the fields, where she can run off lead and i can go 'cross country running' with a fair bit of walking too, for about 2 hours. In the afternoon i go with her, just for 30 mins constant jogging. I'm no fit-freak though, i don't run much faster than a jog, and need to break now and again. But hopefully that will change. It's pretty easy right now for me to dedicate a lot of time for this as i have a window between exams and getting a job later in the summer.