As some might know I am now slowing my cardio down because I was way too high on my heart rate zone.. So walking it is, I went yesterday ( sat. ) To the gym and kept my heart rate in my zone ( 130 ) But in order to do that I had to walk and when it would go down my heart rate I would put some incline on the treadmill to increase my heartrate, Well today I AM DYING!!! My shins are killing me!! My questions are

How do I avoid them, what do I do to heal this or fix the pain, and how long untill they heal?

Am I going to be able to do cardio tomorrow?

Help!