The 5 P's of Running Form
The following article has been reproduced with the kind permission of the author, Matthew Barreau, a USATF Level II Certified Endurance Coach. It analyses the phases of the running stride focused primarily on the lower body's action. Included are details of running drills and their benefit related to particular aspects of stride efficiency.
The 5 P's
There is no clear place to begin talking about the running stride, as each phase's success is ultimately a product of how well the previous phase was performed. As explained later, I believe the recovery phase to be the most important of the running phases. Therefore, I will begin this discussion with the phase immediately following recovery and build up to that crucial phase of form. That way, any errors in the recovery phase, being a product of things happening before it, will be detected more easily.
I have separated the running stride into the Five P's:
The first four are actual phases of the running stride, while the percussion is more of a self-check tool.
The preparation phase begins after the foot has swung down from its recovery phase position close to the upper thigh and come into the position it will hold until impact with the ground. This will be described as when maximum knee lift has occurred (this depends on the speed of the run, where faster running means more leg lift). The foot should be in a dorsiflexed position, with the mid to forefoot falling directly below the knee. As the knee is a support mechanism when running (detailed later), it makes sense that it should be directly above contact with the ground at the time of impact. The dorsiflexed foot will minimize the absorption of running energy by the calf muscle. If the foot is plantar flexed, then as gravity pushes the body downward, the calf will be forced to lengthen to provide a push-off role (see the push-off phase for more details). This eccentric contraction of the calf is too costly, as this type of contraction is the most straining on the body. Landing on the mid to forefoot will also minimize "braking" and trauma on other joints. By landing on the heel, impact forces are transferred up the legs and can even reach the back.
After the leg has got into the position described above, it begins the downward swing to the ground. Muscularly is caused by the extension of the hip muscles (glutes, upper hamstrings). Because of this extension, which will continue throughout the running motion, your foot will be moving backwards upon impact. Therefore, you want the foot to land slightly in front of the centre of mass (COM) so that by the time it becomes "useful", it will be directly under the COM, if not slightly behind. (The moment the foot touches the ground, it has merely made contact and has not yet become a supporting mechanism. Since your body is travelling forward this entire time, the COM will move ahead of the foot strike by the time it becomes a supporter.) Suppose the hip extensors are called into action while the foot is in front of the COM. In that case, they are becoming active in simultaneously pulling and helping support the body's weight, which is a great strain on the muscles and can eventually lead to great hamstring difficulties, including overuse injuries and premature tiring. A "braking" effect will occur if the footfall is in front of the COM. Tired quads can be a product of overstriding, which causes the quads to support the body's vertical and horizontal components. Conversely, if the foot should fall behind the COM by too much, and inefficient falling motion will occur.
The knee must be slightly bent upon impact. This will allow the mid to forefoot to position itself directly under the knee and the supporting system of the body. A straight leg will not only negate much of the lower legs power potential (quads), but it will also cause a greater strain on the hamstring and calf muscles when they are called into action to unbend the joint; moving any joint through a range of motion is significantly easier than the initial unbending of the joint itself.
Heel walks - You strengthen the anterior shin muscles by concentrating on keeping the toes off the ground. This will help keep the toes up just before the foot's impact with the ground, minimizing "absorbing" by the calves.
Toe walks - This exercise strengthens the calves. These are mini-plyometrics, as each step produces a small bouncing motion. During the preparation phase, it is essential to have muscular calves to resist absorbing energy at the point of impact.
A' mechanics- The focus of this drill is to bring the leg as quickly as possible to the position it will be in just before it begins descending toward the ground; the knee will be at its highest point, and the toe will be positioned directly beneath it.
B' mechanics - From the ending position of A' mechanics (knee up, toe up and beneath the knee), this exercise brings the leg down and backward (clawing action). The foot will make a scuffing sound while moving down and back upon contact with the ground.
C' mechanics - This range of motion exercise mimics 'A' mechanics but also includes repeating the motion with the knee pointing to the side. This helps hip mobility while maintaining 'A' form.
For the most efficient stride, all of the energy of motion must be directed in the motion of travel, which, in the case of running, is forward. Any alternative motions are merely wasted energy. The COM should remain at a constant height to eliminate energy use in any vertical component of forces. In analyzing the forces in the running stride, a vertical component is present due to the need to counter the forces of gravity. However, to be most efficient, the forces supplied by the body will be jenough to counter the gravity and not superfluous to that; in other words, no net change in COM height.
The forward motion is caused primarily by hip extension. To maximize each stride, the range of motion of the hip must be adequate to allow for maximal hip extension. The farther one can push with each step, the longer the stride will be (frequency and stride length are the primary components of overall running speed). If you merely extended your hip without changing your knee or ankle angle, you would lower your COM. So, while your hip extends, your knee must extend simultaneously. The ankle comes into play at the end of the stride, which will be examined in the next section.
Walk-through lunges - This motion exaggerates the propulsion phase. Catching the weight on the landing foot will help strengthen the glutes for support while running, and the walk-through motion strengthens the glutes for their role in propulsion.
B' mechanics - The benefit for this phase is merely a continuation of the last phase: in teaching the foot to be moving backwards upon impact with the ground, the glutes will be able to provide more of a propulsion effort to the stride.
The push-off phase is a continuation of the propulsion phase but deserves special attention, as it can help determine whether you run forward faster or run with more of a bounce in your stride. Seemingly more than any other phase, this final push-off will cause wasted energy. The two primary components of the final push-off are near-maximal knee extension and ankle joint plantar flexion. As previously described, the knee is primarily a height maintenance mechanism in the running; as the hip extends, so must the knee.
The knee has yet to extend when the hip is at full extension. Hence, as there is no more extension of the hip, there is no need to extend the knee further. Doing so will only cause a greater vertical component to the running stride and give the sensation of leaping or bounding with each stride rather than running. As previously discussed, completely straightening the knee joint will require undue stress on the hamstrings and calves to bend it for the recovery phase.
The final aspect of the movement aspect of the running stride is the toe-off. After the hip has been fully extended, the ankle joint is the last chance to add horizontal movement and length to the stride. And with virtually no added time cost to this toe-off, there is a clear benefit to the motion. (I say almost no added time because a small-time component is present. For the toe-off to be a horizontal component, the leg must be as far back as possible. The timing of the toe-off also coincides with the beginning of the recovery phase [pull through] of the leg to minimize the extra time of contact on the ground.) To gain the greatest force from this toe-off, the principles of plyometrics must be heeded too: a loaded muscle will provide a greater response than an unloaded one.
When the foot first strikes the ground, the added weight of the body on the calf muscle becomes the loading. If landing with the ankle in a plantar-flexed position, the loading will be too much and too slow. The Golgi tendon organ (responsible for muscle relaxation) will win out, cancelling any potential load-fire coupling benefits. Additionally, any extra strain on the calf from the landing will tire the calf, naturally decreasing its potential to give back energy through the toe-off. Strong quads are also crucial for a proper toe-off, as they will support much of the body's load, leaving the calves available for propulsion rather than support.
Walk-through lunges - As you complete the walk-through portion of this drill, emphasizing the extra push with the toes teaches the body to do the same during the running motion.
Toe walks - If done with a little bounce in the stride, this drill's plyometric effect will give the calves extra strength for pushing off. It is essential to focus on the quickness of the bouncing to desensitise the Golgi tendon organ, which causes muscle relaxation. This would diminish the calves' abilities to provide extra inches to stride length.
When training the body, it is said that performance increases come during the recovery phase rather than during the actual training session. The same principle can be applied to the running stride; the improvements in stride efficiency will come from the stride's recovery phase or how fast you can get the leg through to begin the next preparation-propulsion-push-off cycle.
The pattern of movement for the pull-through phase can be classified by the pneumonic "heel up, toe up, knee up." The "heel up" begins with the toe-off creating the heel to rise, and continues with the need to get the heel to the upper thigh as quickly as possible. Again, this emphasizes the need for a toe-off motion to complete the stride propulsion phase. It will shorten the lever that needs to be brought forward, creating a faster pull-through stage.
The toe-up and knee-up coincide (keep in mind that all three of these events happen nearly simultaneously, as the goal is to have them occur as quickly as possible). As the heel is brought to the upper hamstring, the knee is already driven forward. As the foot swings through, it is dorsiflexed (toe up) and placed in the position it will remain in until it is in contact with the ground. This flexing of the anterior shin muscles also helps begin flexing the knee.
Bringing the knee up is almost a misnomer, as it gives the illusion that the goal is to create a vertical movement component. However, the primary thought behind "knee up" is to allow the lower leg a slight amount of extra time to fall into position for the landing. Essentially, this is a slight pause in the upper leg's motion while the lower leg uncoils.
Carioca - The major action in this drill is the quick raising and lowering of the rear leg. The emphasis on quickness and raising the leg will greatly involve the hip flexors, the primary movers in the pull-through phase.
Walk-through lunges - When beginning the walk-through motion, the movement pattern mimics running. Getting the leg through is essential in this drill because if you do not, you will fall, essentially the same as running.
'B' mechanics - These drills can emphasize leg recovery, especially when doing exercises such as a continuous fast leg. To focus on the pull-through phase, begin with the hip fully extended and do heel-up, toe-up, and knee-up as quickly as possible.
'A' and 'C' mechanics - These drills are involved with this running phase because they strengthen the hip flexor muscles. For best results, focus on the quickness of hip flexion.
Bringing the leg close to the body involves more than just creating a shorter lever for quicker movement. By bringing the lower leg up against the upper leg, the hip flexors (a traditionally weaker muscle) do not need to exert as much force during the pull-through phase. Instead, the hamstrings help support the lower leg's weight during this phase. Raising the leg higher will also make the legs less of a rotational force. Because of this, the upper body does not need to counteract as much rotary movement, allowing for a more forward-focused movement. A strong core will assist even more with this process, providing additional inhibition of rotary motion through its stabilization properties.
The final "P" of the running stride is percussion. This is merely a means of self-check-in without technical coaching and video equipment. Looking in a mirror does not provide great feedback, as a head-on mirror will reflect too small an image and not allow adequate time to reach a cruising speed (when a patterned stride occurs). A mirror on the side requires a head turn, which is not a natural part of the running stride and will provide an inaccurate assessment of form. Energy cannot be created or destroyed. It merely changes conditions during its existence. One of these forms is movement, and another is sound. Optimally, the goal is to put total energy into motion while running. This leads to the assumption that the most efficient stride will also be the quietest (assuming all other things are equal). The sound produced by your feet hitting the ground is a transfer of energy your body is making to the noise you hear and is a result of the vertical component of force you place into the ground (and it, conversely, gives back to you). Some vertical features will always be necessary for a gravitational environment so that some sound will occur. The goal is to minimize it.
Running - From one thing evolves another, and such is the whole of the running motion. As running is a cyclical pattern, an error can often compound itself. Ultimately, the most basic form is the sound of the foot made with the ground. Any noise is a transfer of energy in a downward motion rather than the forward movement of running.
Upper Body action
What to look for in a runner's upper body:
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