Push sleds have become a popular form of exercise for increasing running power, developing muscle mass in the lower body, and as a form of energy system training to improve muscular endurance and body composition. One additional advantage of a push sled, specifically the type with high vertical handles that enable you to run more upright, is that it can help improve running technique.
When you push a sled, your arms are relatively rigid, although some slight flexion is necessary to reduce the stress on the elbows and maintain better control of the sled. But my point is you don’t have to concentrate on upper body mechanics as much with a push sled, and this difference allows you to focus more on your leg drive. For example, an athlete may not have his or her feet in alignment when running, making for inefficient movements and putting excessive stress on the joints. As the athlete pushes the sled, a coach can stand behind her or her and easily notice faulty running mechanics of the lower body. And it should go without saying that you should not use weights on the sled that are so heavy that they cause a breakdown in mechanics during any part of the sprint.
An athlete trying to improve running speed seldom wants to push a sled for more than about 25 yards, because after that distance the body usually moves into a more upright running stance. It would also be a good practice after performing several sets of upright push sled work to perform a few sets of regular sprints, as this will help reinforce correct running mechanics. Repeats of 5 to 10 meters tend to be the best approach when you want to learn develop the strength to overcome inertia.
Copyright ©2011 Charles Poliquin