Question: When they test to see how good a football player is going to be they measure how fast he can run the '40' or 40-yard dash. Is there a way to train for running the '40'?
Answer: When they are talking about your '40' time they are measuring an athletes' 'burst speed'. Burst speed is the type of speed you need for very short sprints. Burst speed can be improved by sprinting all out for 5 to 15 seconds during every minute of a 3-mile run, or by doing pure speed sprints. For speed sprints you rest completely between sprints so that you can run all out during every effort.
Burst speed workouts are not for beginners. Even experienced runners should work into pure speed workouts, starting their sprint from a running start rather than from a still position. Remember to warm-up thoroughly and stretch thoroughly, and also to strength train the muscles of the legs with weights. The most important strength training exercise for speed development is the squat.