You should always do a nice warm up before you go running. If you don't your chance of injury increases greatly.
You should always stretch before and after as well. Always. You should even stretch everyday if you have the time. Back in high school I had a running coach who was 42 years old, but could still jump 26 feet. That is good enough for the olympic team. He said the reason he could jump so far at his age is because he had stretched everyday since he was 19.
Usually when you run long distances, run heel to toe. Running on the balls of your feet puts more pressure on your knees and is harder on them. Usually you should only run on the balls of your feet when you are sprinting. Unless your running a marathon, run heel to toe.
You should always run on the softest surfaces possible. This can help lessen the impact to your knees and will prevent injuries and wear and tear to your joints and ligaments.
If you get tendonitis, take flax seed oil. That helped me clear up the tendonitis quickly when I got it. For joints and ligaments, take glucosamine chondroitin. That helps repair them and make them strong.
I have had several top running coaches and have ran at TOSH. So I'm not just talking out of my ass
