To you, what’s the hardest thing about running?

Consistency!  One day I can go out and crush 14 miles without thinking about it and the next day 2 miles feels like the hardest run of my life (or the next week, time matters not in this vortex). 

I believe this has a lot to do with my head space.  I know my body can do it, but some days I just cannot get out of my own head. 

Running is about 25% physical, 75% mental… maybe more of a 10%/90% on most days.