Want to enliven your action shots? Blur is the key.
For simple blur: Drop the shutter speed one or two notches below action-freezing speed to blur the hands and feet of runners, the spokes and pedals of bicycles, etc.
Add flash for ghosting: With flash on relatively close subjects, you can lower the shutter speed even further. Use second-curtain sync to get a ghost trail behind the subject.
Pan with the motion: Use very slow shutter speeds to blur the background into a streak.