Ever feel pain in the bottom of the foot? Chances are it is plantar fasciitis (an inflammation of the plantar fascia that runs along the bottom of the foot).
While we have a number of stretches we do as a part of our warm up, we have many of our students running more in the summer (playing soccer etc.) and feeling the pain.
Here is a great video from Kelly Starrett at mobilitywod.com on what can cause it and how you can fix it. If it is really bothering you then you should see a physio or chiro.