The model of running shoe should be repaired. Pronation, motion control, cushioning and stability shoes? Get rid of all.
It's not just barefoot towards minimalism, and the running shoes that depict either / or situation of many one. And 'much deeper. Nor is it that companies running shoe from wrong and having to make a profit. Shoe companies can achieve their goals for, but perhaps not the objectives of its purposes, what must be done. TheParadigm that running shoes are built on is the problem.
Running shoes are built on two central sites, the impact forces and pronation. Their goals are simply to limit the impact forces and prevent overprontation. This has led to a classification system for the control cushioning, stability and movement based off. The problem is that this system can not land under their feet. We focused on the wrong things for 40 years?
I'll start with the usual statistics 33-56% of runnersare injured each year (Bruggerman, 2007). It is a kind of mind blowing when you think about it. Since there is a lot of injuries, let's see what are the shoes.
Pronation:
As already mentioned, the shoes are on the premise that the impact forces and pronation, resulting in injuries constructed. Pronation is designed as the bane of all runners. We have been inundated with limitation of pronation and motion control shoes. The central idea behind pronationoverpronating is that the rotation causes the lower leg (ie ankle, shin, knee), putting stress on your joints and cause damage. Running shoes are designed to limit these so pronation. In essence, running shoes are designed and built to put the body orientation "correct". But we really need the correct orientation?
This paradigm of pronation is based on two main things: (1) pronation causes injury and (2) running shoes pronation may change.
With regard to thefirst premise, we can see that several studies show a relationship between pronation and injury. In an epidemiological study by Wen et al. (1997), found that the orientation of not less extremitly was an important risk factor for marathon runners. In another study by Wen et al. (1998), this time a prospective study, concluded that "small deviations in alignment of the lower limbs do not seem to fit the most important risk factors for overuse injuries of riders." Other studies have reached similarConclusions. One of Nigg et al. (2000) have shown that lesions of the foot and ankle did not predict the movement in a large group of runners.
If not the movement of the feet / pronation predict injury is or is not a risk factor for injury, then one must ask whether the concept works or sound ...
Regarding the second premise, nor can you modify pronation shoes? Motion control shoes are designed to reduce pronation through a variety of mechanisms. Most choose to do a post or an insert mediasimilar device. In a study of Stacoff (2001) have tested various devices for controlling the movement and found that the shoes do not change anything that does not change the kinematics of pronation and tibia bone of the heel. Also found another study by Butler (2007), motion control shoes showed no difference in peak pronation shoes than damping. Finally found Dixon (2007) show similar results, that the motion control shoes do not reduce peak eversion (pronation) and do not change theConcentration of pressure.
It is a sort of double whammy on motion control shoes. When excessive pronation does not cause injury to the extent that everyone thinks, and if the shoes motion control does not change you, not pronation, what is the meaning of a motion control shoe?
Damping:
Shock to the bad injury other great race. The thinking goes like this, the greater the impact force on the lower leg, the greater the stress takes its foot / leg, leading tocan lead to injury. This fear, running shoes, especially damping are those who fight to save. Let's take a look.
The first question is, cushioned shoes do its job?
Wegener (2008) tested the Asics Gel-Nimbus and Brooks Glycerin to see if they reduce plantar pressure. They found that the shoes do their job only !.... But where the pressure varies greatly reduced. Which means that the reduction of pressure between the front / rear foot / manifold etc.. This has led to interestingHe concluded that their should be a change in the prescription of shoes at a base in which the plantar pressure is higher for the individual person. It should be noted that this reduction of pressure on a comparison with another shoe, a tennis shoe rested. I'm not sure that this is a good control. In essence, this study tells us, cushioned running shoes which reduce the peak pressure, compared to a tennis shoe.
In a review of this topic, Nigg (2000) found that the effects of both external and internalThe peak forces were not or little affected soled running shoe. This means that the damping does not change the type of impact forces much, if at all. But how can that be? I mean, it's common sense, if you jumped on the cement at the surface of foam jumped on a shoe, soft surface of the shoe is right? We returned to this question in a minute.
The forces of impact: The picture is sad:
But it is not so simple as described above. In an interesting study by Scott (1990) sawPeak loads in various locations of injury likely for runners (Achilles, knee, etc..) All peak loads occurred during the middle position and push. This has led to a realization that important "was the driving force of the heel contact any influence on the maximum power estimated by the chronic injury sites have seen," and led to speculation that led to injuries not related development impact.
Even more complicated is the idea of motion is that when looking at injury rates than those on a hard surface orsoft surfaces, no protective benefit appears to run on soft surfaces. Why? Because of the so-called pre-activation and muscle-tuning, which are discussed below.
Supporting these data, other studies have shown that people who have a low peak effect violated the equal chance to obtain as those with a high peak impact force (Nigg, 1997) to have. If you want to further complicate things, the impact seems to be the driving force between the increase in boneDensity.
As a coach or trainer, this should make sense. The bone reacts to the stimulus of more and more against them if the stimulus is not too big and there are a lot of free time.
Underestimation of the body: the impact forces as feedback:
Back to the question I asked was: How can you not change the impact forces on the sole basis of softness and because it is not running on hard surfaces cause more damage?
The problem is, once again, we underestimated the human body! This is aincredible thing, and we give them the recognition they deserve. The body adapts to the surface, goes on strike, if you give them a chance. The body adapts to a shoe-surface adjustment and the impact forces on the changes in stiffness, the way in which the blows of the foot, and a concept called muscle-tuning.
An example of this is to see with bare feet, denies reduced proprioception (sensory feedback) to wear a shoe with cushioning of the shoe. Studies using minimally shoes / barefoothave shown that the impact forces the body to adapt / landing on the feedback and feedforward information appears. When running or landing from a jump, the body takes in all the sensory information, as well as previous experiences, and adjusts itself automatically to protect / country optimally As mentioned earlier, this is through a variety of mechanisms. You will have a cushioned running shoes stick to the bottom of the foot and the body: "Oh, we're fine, do not impact on the concerns that we have this piece of softRubbish on the foot.
A concept that needs to be further discussed, is muscle-tuning. It 'a concept recently by Nigg et al. in 2000. See weight as a signal or a source of feedback, as I said before. The body uses this information and turn on the vibrations of the soft tissues and / or bone to minimize vibrations. His thesis is that influence is not the problem, but the signal. Muscle-tuning is essentially the control of these vibrations in a wide range ofMethods. One possible mechanism is pre-activation. Pre-activation is the activation of the muscles prior to impact. In this case, serves as a kind of muscle up to prepare for impacts and may also include muscle stiffness, which is another way to prepare for the impact is to change. EMG pre-activation with a number of studies have shown.
Shoes implications not only surface but also the correct type. As mentioned previously, the variation of the sliding surface has no influence on accident rates. Why? Probablybecause the body adapts to go. In an interesting study to measure the muscle activity was O'Flynn (1996), changed the pre-activation based on a surface. To prepare for the impact, and presumably to minimize muscle / bone vibration, when he was in specific pre-activation is very high, when on a soft track, not so much.
All this means that the body adapts to sensory stimuli. It has various methods of adjustment. Interested in how a shoe fits. The shoe is notto do something to change the damping, it is easy to change how the body reacts to impact. There is a clear position to jump, if you think about it. Here's the summary: The type of shoe and shoe material changes due to the effects of non-alignment of the leg or changes in attenuation. In contrast, changes characteristics implications, because it alters the sensory feedback.
Finally, the concept of damping. Well, what we should try to capture? Heel impact forces are notshown to influence injury, in fact, in one study had little impact runner, an injury rate of 30% compared to an injury rate of 20% in high impact runner. Shoe midsoles will not change or change only marginally impact forces in any case. So, not only the damping is not the answer, the shoes could not do their job. But what about studies that show a better cushioning shoe absorbing midsole with her again? Well, this is the majority of that exam done by a machine to simulate the effectsForces occur during execution. Well, yes, a pillow may have more impact, but did not take into account the role of the body adapt to the effects of feedback.
The basic damping does not work? As the body adapts based on feedback and feedforward information. These results prompted an extraordinary researcher (Nigg, 2000) to revise the paradigm of damping call for running shoes.
Go barefoot?
Fast, this problem could not be completelywithout a brief mention of walking barefoot. An interesting thing to note is that the initial impact force peak is free to run barefoot, as compared to running shoes. This means that to see the impact forces such as (A) for shoes, and (B) for bare feet. The first little blip A is the first punch. There is a hypothesis that the initial impact, it must do to injury.
A recent study Squadron et al. (2009) in comparison with running shoes, barefoot, andRun in Vibram Five Fingers. Showed reduced impact forces, ground contact and the shorter stride length, step frequency but increased when walking barefoot (and Vibram) compared to running with shoes. This is not unexpected, but it shows that running shoes, in fact, change our normal rhythm. An interesting point is the reduction in stride length, but increased pedaling rate. Shoes tend to be the length of the pitch than those of a series of ground contact and frequency of support.This happens because of changes in the feedback signal to land on the heel more likely to tense, weight gain, all leading to more time on the floor. And 'interesting to note that all elite runners have ground contacts short and high frequencies (eg through the study often quoted by Daniels, 180 steps per minute in the figure).
Tie them to the discussion above the body to control things based on sensory information, such as walking barefoot, there is a higher degreeStiffness in the lower leg. Increased stiffness, increased SSC (stretch-shortening cycle) as a consequence, resulting in greater force on the next push-off (2001). Dalleau et al. demonstrated that the pre-activation causes increased stiffness improves running economy. In his study, was the energy cost of running for the rigidity of the lower leg (1998) in relation
Another recent study found that a pair of knee flexion were the knee varus torque and the torque of internal rotation of the hip allsignificantly higher than the shoes with bare feet. What does this mean? Maybe it means more stress on the joints in this area. Dicharry Jay said it best when he says:
"The soft materials in modern running shoes provide a way of contact that would not use bare feet. The foot is no longer receiving proprioceptive signals shod. The foot naturally rise to surface quickly, but a mid-sole, the foot may be able to answer, hit the ground. This dumb, orFeedback to alter the body during the race. These factors allow a runner of a band that the force majeure reasons noted above. "
The only thing that supporters use to hit metatarsal strike non-barefoot/heel / reject barefoot is the Achilles tendon. You're right to say that the strain of the Achilles tendon is higher than runner midfoot striking. The Achilles is to take a big load. The problem is that we have weakened the Achilles by years of wearing shoes with highHeels. In essence, it means the problem of Achilles with the shoes, so that you create. The Achilles is designed to operate in a spring like fashion .. During the impact, such as braking or contact phase is in operation, energy is stored in the Achilles tendon and later, the recoil energy of the stage during the performance. The Achilles' save, and again approximately 35% of its kinetic energy (Ker, 1987). Without these elastic storage and return, the oxygen consumptionrequire 30-40% higher! So, in terms of performance, because we try to minimize the contribution of the tendon? It 's like giving away free energy.
Running shoes are not using the storage and elastic recoil, as well as shoes or bare feet minimum. More energy to walk barefoot with shoes (Alexander and Bennett, 1989) is lost. Moreover, in some models of shoes, the arch is not working as a feather. The arch of the foot can save about 17% of the kinetic energy(Ker, 1987). In light of these results, it is not surprising that when they walk barefoot with shoes in comparison is more efficient. Several studies have shown decreased VO2 in tandem with the barefoot, even if the weight is taken into account. This should come as no surprise, as I said, without elastic recovery VO2 requirement would be 30-40% higher. Run in a shoe at least makes better use of the system.
So, the message is that the shoes away from natural changeMechanical one, the mechanical changes that are not optimal for the operation to create quickly (reduced frequency step closer contact with the ground, reducing the rigidity of the system, reduced the contribution of elastic, and so on).
Tie together with the elite:
As for elite athletes, such as racing and training, generally have higher turnover, low contact time on the ground and strike the foot, which is below its center of gravity. Since most of the elite have the sameProperty during the race, it makes sense that this is the best way to get to run fast. So why do we wear shoes that are designed to increase contact with the soil, reduce turnover and promote exhaustion before moving the center of gravity? I have no idea.
Conclusion:
As a result, I am not a fanatic shoes tell the trenches now. You've probably run in shoes for 20 years. His body has made some adjustments during this period. You have to change gradually, if youwant some of the changes needed.
The purpose of this article was not to talk about the benefits of running barefoot. Instead, it was pointed out problems with the performance of classification shoe. There is a paradigm of damping / pronation, which is not as true as it would have us believe, is based. The paradigm needs to be reevaluated. It is not based on good science, but the first ideas that make sense without the science behind them, but further examination was not the test. Arecent study has shown that with the good old system of classification shoe that everyone uses, has had little impact on the prevention of accidents in a large group of participants from Army basic training (Knapik, 2009). They concluded that (like all great magazines to recommend the execution) the choice of arch height shoe base is not necessary if the goal of accident prevention. I think that means breaking systems ...
Where are we going and how we can solve the problem? I have no idea. Sorry, no answer here genius. My inclinationis that we are about to leave the function of the foot to function as it should be objective, or at least come up with a pair of shoes, the mechanics of the foot may change, but still allows for feedback / features of the body. The first step is the foundation on which running shoes, motion control, stability and cushioning looking paradigm established. My opinion is that they are reassessed. I'm going with what I said above, but it is an important concept to convey:
The body iscomplicated and intelligent than we give him credit. The type of shoe and shoe materials or characteristics of the changes of pitch effects because the orientation of the leg or changes in attenuation. In contrast, changes affect the properties and the length of the pitch, because it alters the sensory feedback. The brain is a wonderful thing. "
If you found this informative article, I would be grateful if you passed it. The goal is for the research-based data from there, so that people canwell informed.
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