Weight Training for Running
If it comes down to a choice between weight training and extra running, choose weight training (ideally three times a week). Weight
training (preferrably free weights, versus machines - bench press to help your arm lift, squats to increase your push power, leg curls to
increase your kick, toe raises to increase your ability to stay on your toes, ab exercises to increase your overall stability, etc.) not
only increases your sprint power and endurance, but also strengthens your connective tissues and thus helps ward off injury (allowing you
to train harder and longer).