Getting Back Into Old Habits

I went for a run today - for the first time since starting med school, hurrah! It felt great to get out there, but man, am I unfit! I'm not too sure what prompted me to go for a run today of all days, but I think there was something to do with it just being such a beautiful day that after classes I desperately wanted to be outside. Hopefully I'll be able to get back into it, rather than living with the paranoia that I can't do anything aside from study and sleep.