A: As Arthur Lydiard described it, hill repetition training is used to provide specific strength training prior to undertaking faster, more anaerobic training. We recommend three basic types of hill repetitions: hill bounding, hill springing, and hill charges. When hill bounding, select a moderately-sloped hill (4-6% grade) that will take about 1:00 to climb and use a slightly exaggerated stride length, pushing forcefully off the back foot and using high arm swing to drive the knees up and forward. When hill springing, select a more steeply-sloped hill (6-10%) that will take about 30 seconds to climb and use a more spring-like technique, focusing on vertical displacement. As before, drive hard off the back foot and really swing the arms in exaggerated fashion to drive the knees up and through like a sprinter. Last, when performing hill charges, find a very steep hill and do repetitions of 15-20 seconds, focusing on powering up the hill while exerting a lot of push with the glutes and quads—technique is less important here; but, maintain an upright posture, if at all possible. The recovery interval for all of these should be an easy jog down the hill, resting at the bottom with some light jogging if extra recovery is needed. You should not feel terribly winded doing any of these exercises—this is localized anaerobic work that uses your body weight as resistance. Think of this as very functional plyometrics. – Jonas Holdeman

Incidentally, using a heart rate monitor has robbed the joy out of running for me. My legs die way before my heart