What kind of exercise should you do during a warm-up?

If jogging you should start off with a brisk walk and transition after about 1 minute to a slow jog. Then pick up your pace as your legs become warm with increased blood flow. If biking you should do a few static calf and thigh stretches but don't extend too far as muscles are cold. Then start off your cycling at a very slow comfortable pace. After about a minute you can start to slowly increase your pace until you reach your goal.