High Intensity Interval Training, HIIT

Because High Intensity Interval Training puts such a tremendous strain on the body, it is important to take the necessary precautions in order to avoid injury. An initial warm-up light jogging, for a a few minutes will get your heart rate up, and blood flowing to your muscles. Stretching is a very important component to high intensity interval training. If you are choosing to sprint for your HIIT exercises, stretching the hamstring, and quadriceps are absolutely key to avoiding injury and soreness.
You also want to make sure that the area you will be performing your exercise is free from brances, rocks, any sudden holes, or any other obstacles that could get in the path of your sprint.

Check out this video with some very good information about HIIT