http://www.RunningByGeorge.com. When you run, you need to breathe. Duh. Trouble is, not breathing correctly can limit your performance as you don't get enough oxygen into your lungs. By establishing a rhythm with your breathing right from the start of your run you can use it to regulate your intensity and ensure your muscles are getting enough oxygen. I recommend breathing in for two breaths and out for two, with each breath coinciding with your foot landing on the ground. Use this tempo as your base for all runs up to and including threshold intensity. For anything above that you might want to increase the rhythm to a "one in, two out" which circulates the air a little quicker.
Even though I like to think I know it all, I have to admit there are lots of other experts out there with far more knowledge on specific aspects of training and nutrition than me. Rather than sitting in the corner and sulking about this, I track them down and interview them to extract the good stuff.
These are all video responses to questions I have received via email. If you have any questions of your own, film yourself asking your question and I'll do my best to answer it with another video of my own :)