As a runner you might not think about training your shoulders, but strong shoulders will improve your posture. It can also improve your arm swing and help you drive up that steep hill.
Warm up
Warm up your body by increasing the blood circulation. Run on the spot for one minute. Squat down and touch the floor 10 times. Rotate your arms forwards and backwards. Start with small circles and increase the size. Repeat these two exercises twice before starting your workout.