Running and Mouth Breathing

Question:

I am 17, I run cross-country and middle distance track and I have been trying to figure out the best method of breathing. For a long time now I have been breathing in and out of my mouth. I have experimented with changing the speed of my breathing with different paces. I thought that the best way to breath would be to take longer breaths and to exhale fast. Is that a good way of breathing? NO
From what I have picked up the best way to breathe while running is in through the nose and out the mouth. NO

I have been trying to breathe this way while I run, but when I get tired I start  breathing back through my mouth only. Is there anything I can do to correct this, or should I breathe a different way?

From Mike:

It is better to breathe in and out thorough the nose. Try filling your mouth with water and run that way, slowly at first for you can get used to it. Or count clearly in a whisper as you run. Let me know how that works for you. Read ALL the pages of this website starting with exercise and FAQ and tips. Get the Sports Performance Program