One of the most common kinds of injury is due to a tightening of the iliotibial band (ITB), a ligament which runs all the way from the hips to the feet. When it tightens and contracts due to exercise, the places that tends to feel it is around the outside of the knee. Here are a couple of stretches you can do to loosen up the ITB before and after racing:

Floor stretches

These can be used after a run or in between runs. If doing after a run, it is probably a good idea to start with the lighter standing stretches immediately after the race, and do these floor stretches after 15 minutes or so. Both these stretches affect the right hip area; to . If doing in between runs, make sure to do some warm-up exercise first so the muscles aren't pulled from a state of total inactivity.

Stretch 1:
Lie flat on your back. Bring your right foot over your left leg and place it beside the left knee. Now, with your left hand, pull your right knee . you should feel a stretch in the hip area: this is one of the main areas where the ITB tightens. Gradually pull the right knee until you feel a slight discomfort; then release your knee, place your hand the other side of the knee and push your knee against your hand with twenty percent of your strength. This engages the complementary muscles to the ones you are trying to stretch and makes it easier to push the stretch further. Then do the stretch again, this time pulling your right knee over much further. Go as far into the stretch as you feel comfortable.

Stretch 2:
Again, lie flat on your back, this time with your left knee bent. Place your right ankle on top of your left knee. Grab your right knee with your left hand, and your right ankle with left hand, and pull in a direction 90 degrees to the line if your right leg. Similarly to stretch one, pull until you feel a stretch in the hip area, then place your hands the other side of the leg and push with twenty percent of your strength. Then do the stretch again as far as you can go.

Standing stretches

Stretch 1
This stretch affects the very side of the hip, right at the beginning of the ITB. Stand about a foot away from a post or park bench, holding on to it with your right hand and facing 90 degrees to it. Put your left foot over your right foot Now allow your left knee to bend, and your left leg to slide away from the post, so that your body forms a curve away from the post.

Stretch 2
This stretch can be felt all along the ITB, but particularly below the knee area, and can be done freestanding. Place the left leg over the right leg, place both hands over each other on the left hip, and bend over at a 45-degree angle. I was told some Kenyan runner was a big fan of this one, I forget who :)

Stretches before running

Before running, your stretches should have a dynamic aspect to them. One good way to stretch the ITB is to stand holding a post or park bench in front of you. Then gently swing one of your legs from right to left like a pendulum. (I saw this one used by someone who does ballet :) ) Repeat with the other leg.