Sprinting Mechanics Made Simple: Maximizing Acceleration
With team sport athletes, teaching the concepts of proper acceleration mechanics is vitally important. Most of these sports primarily rely on short bursts of acceleration covering <20 yards. Using the coaching acronym PAL (Posture, Arm Action, and Leg Action) is a simple technical coaching model that can help develop proper sprint mechanics. One of the great benefits of the PAL coaching model is that it breaks down complex movements/techniques of sprinting into more easily digestible parts. Here we will break down each segment of the PAL.
Posture
Posture is arguably the most important part of proper sprint technique. Since the body is a kinetic chain without good posture the forces you’re producing to run fast will instead dissipate resulting in less power and slower sprint times. This is known as an energy leak. An energy leak can be defined as the lack of proper energy transfer, and a subsequent deficient movement which results in decreased output, in this case speed. Posture also allows us to appropriately orient force in the direction needed, which is typically either horizontal or vertical depending on what phase of sprinting you’re in. Again, exact posture is dictated by what sprinting phase you’re in (acceleration or max velocity), but generally speaking in the initial phase of acceleration we like to see a projection (torso) angle of roughly 45° in relation to the ground with a smooth/gradual rise over time.
Arm Action
The arms in sprinting are used as a counter-balance to help manage rotational forces generated from aggressive leg action allowing athletes to keep force production going straight ahead. The arms also help to synchronize efficient leg action for better force production. In regard to mechanics, the arms should be going cheek to cheek (butt cheek to face cheek) and be synchronized with the opposing leg. They should be moving parallel with each other, and have little to no side-to-side movement. Finally, the elbow should to be bent at 90° with a slightly closed angle for front-side mechanics and slightly open angle for back-side mechanics, while staying as relaxed as possible through the shoulders and hands.
Leg Action
Leg action in acceleration should mimic a pistol like motion, with the feeling of punching the ground. The shins should also demonstrate a positive angle, meaning they’re more parallel to the ground. The knee and ankle should be flexed at a 90° angle and rigid on the front-side mechanics to allow for max force production when striking the ground. It is important to make sure that the foot strikes underneath (or slightly behind) the center-of-mass to maximize projection and minimize any breaking forces that come from over-striding. As athletes gradually transfer into max velocity the leg action goes from being more piston-like to more cyclical in nature.
The PAL coaching paradigm is a great strategy for developing the fundamentals of proper sprinting mechanics, and is an easy way to explain complex movements to athletes. Improving sprinting mechanics will help athletes:
· Synchronize explosive upper/lower body movement
· Optimize directional forces that support efficient acceleration
· Reduce energy leaks and wasted energy
· Reduce the likelihood of soft-tissue injuries
· Maximize current speed potential through appropriate muscular length-tension relationships
If applied appropriately and in conjunction with a well-rounded speed, power and strength program this simple frame-work can drastically improve an athletes sprinting ability!
Erik Jernstrom
Director of Sports Performance @ EForce
