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Its does not matter which way you run, there is an injury risk associated with each running form!
If you forefoot strike --> increased forefoot dorsiflexion moments on rearfoot; increased dorsiflexion moments at ankle; increased rearfoot inversion moments --> all these will do is increase the risk of injury in the structures that those moments.
If you rearfoot strike --> increased rearfoot impacts --> increase the risk for ijury associated with higher rearfoot impacts.
Its six of one, half a dozen of the other ... its all depends on the injury profile/history and which tissue you want to off-load.
BTW -- have you ever tried to midfoot/forefoot strike in a military boot?
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Re: Podiatrist Recommends Forefoot Striking Versus Orthotics for Treating Running Injuries
Heres what I think, it's a bit "selfish gene":
1) the body doesn't want to injure itself
2) the body wants to be as efficient as possible to get you from a-b safely so that when you get there you are able to reproduce
3) the kinematic pattern the body sub-consciously adopts during walking or running is the bodies best attempt to avoid injury while being as metabolically efficient as it can be. Viz. "the machine might know best"
4) Consciously fannying about with running strike pattern is consciously overriding the bodies self-defense mechanisms and probably increases the risk of injury- now there is a prospective study... does fatigue increase the risk of injury? -
Re: Podiatrist Recommends Forefoot Striking Versus Orthotics for Treating Running Injuries
I would basically agree with your summary. However, from my experience as a runner and a clinician, there does seem to be a learning process required, which requires a finite amount of time, for each individual to learn to run the most efficiently.
Individuals who ran for many years as children and in their youth rarely need any additional coaching to run efficiently. However, adults who are just starting to run for the first time since their school gym class over 10 years ago, and who did no running sports as a youth, may require a year or more to learn to run efficiently. The neuromuscular patterns must be developed sufficiently to allow the individual to run smoothly and efficiently, given their own peculiar set of biomechanical characteristics.
During my exercise physiology courses at UC Davis, I remember learning about how running faster speeds, as required in racing, needs to be simulated during training not only to increase the metabolic capacity of the individual but also to develop the neuromuscular coordination to run with a faster speed with better motor coordination. I certainly experienced that "neuromuscular coordination training effect" during my many cross country and track seasons when my ability to run, lets say a 440 yard interval at 70 seconds, seemed much easier mechanically to do when I had already been running these repeats for the last three to four weeks, rather than on the first 440 interval of the season.
The same neuromuscular coordination training is required for finer motor skills such as playing piano or violin where the mechanics of playing these instruments will become more efficient with increased duration and frequencty of training of the neuromuscular system. Therefore, before we consider trying to "retrain" a runner's kinematics, consideration should be given to the amount of time that individual has been a runner and how much they have run over their lives. For these reasons, I am much less likely to suggest changes in running kinematics with experienced runners than beginning runners on "proper running form". -
Re: Podiatrist Recommends Forefoot Striking Versus Orthotics for Treating Running Injuries
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Re: Podiatrist Recommends Forefoot Striking Versus Orthotics for Treating Running Injuries
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Re: Podiatrist Recommends Forefoot Striking Versus Orthotics for Treating Running Injuries
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Re: Podiatrist Recommends Forefoot Striking Versus Orthotics for Treating Running Injuries
Anecdotal observation suggests that forefoot strike tends to occur under metatarsal heads 4-5, which should mean either the STJ axis has to be very laterally deviated at this time and or the reaction force vector contains a significant medio-lateral shear component in order for the external inversion moment to be greater in forefoot strike running when compared to rearfoot strike running :confused: -
Re: Podiatrist Recommends Forefoot Striking Versus Orthotics for Treating Running Injuries
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Re: Podiatrist Recommends Forefoot Striking Versus Orthotics for Treating Running Injuries
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Re: Podiatrist Recommends Forefoot Striking Versus Orthotics for Treating Running Injuries
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Re: Podiatrist Recommends Forefoot Striking Versus Orthotics for Treating Running Injuries
No researcher that I know of is actually tracking the STJ axis other than Steve Piazza.
http://www.biomechanics.psu.edu/piazza/research.html
Everyone else is using the center line of the foot as their "inversion-eversion" axis of the foot, even though this will always produce erroneous results in regards to STJ axis external and internal moments.
Much more work needs to be done in this regard. -
Re: Podiatrist Recommends Forefoot Striking Versus Orthotics for Treating Running Injuries
Hi CT and Ian,
thanks for the extra info, from my converstaion with the Physios that exactly what they were saying and they are getting large numbers with Anterior compartment injury/strains and from the refernces from Craig I would have to agree that it would reduce stresses and forces on the anterior compartment.
although as Kevin says changing the pattern in young recruits who are generally fairly fit and usually running well without problems they may start to see other issues .
again it probably is a horses for course issue, that is picking the correct treatment to suit the symptoms in front of you and using all available ideas as appropriate- and I guess thats the key! -
Re: Podiatrist Recommends Forefoot Striking Versus Orthotics for Treating Running Injuries
http://w4.ub.uni-konstanz.de/cpa/article/viewFile/451/391
Much sense in that one.
P.S. If anyone can access and translate them from German, according to the paper these should show that injury occurs in forefoot strike runners as frequently as they do in rearfoot strike runners- just in different places.
Kleindienst, F.I. (2003). Gradierung funktioneller Sportschuhparameter am Laufschuh. Shaker. Aachen, 234-235.
Walther, M. (2005). Vorfußlaufen schützt nicht vor Überlastungsproblemen. Orthopädieschuhtechnik, 6, 34.
Would be interesting to see the differences, if you can arrange it Craig. -
Re: Podiatrist Recommends Forefoot Striking Versus Orthotics for Treating Running Injuries
If the external inversion moment is higher in forefoot strike running yet the rearfoot eversion velocity is higher, it must mean that internal eversion moments are even higher in forefoot strike running- right? Which could indicate increased activation of the evertor muscles or decreased activation of the invertors- EMG anyone? -
Re: Podiatrist Recommends Forefoot Striking Versus Orthotics for Treating Running Injuries
Anecdotaly, I now running 2 days/week in my NB minimus and 2 days in my Hoka maximalists shoe. When in the minumus I actively invert the rearfoot more --> post tib working harder --> does that mean the inversion moment is higher and that why post tib has to work harder??? -
Re: Podiatrist Recommends Forefoot Striking Versus Orthotics for Treating Running Injuries
That's the key, differentiating internal from external moment. It would make life much easier if authors would make that differentiation.
But, if we see a higher eversion velocity with a forefoot strike it means that either the internal eversion moment is increased (which shouldn't come from your tib. post) and/ or internal inversion moment is decreased, and/ or that external inversion moment is decreased or external eversion moment is increased. See how confusing that is even when you define internal and external moments.
I suspect that your observation of increased tib. post. activation may be accounted for by an increase in external eversion moment in association with forefoot strike (assuming that you forefoot strike in your minimalist shoes- do you?). As would the increase in eversion velocity reported by others. But lets see...
Gets even more complex when we consider that when a muscle generates an internal moment it also generates an external counter moment when the foot is in closed chain... how is that we move again? Which I guess gives rise to the contention that muscles merely stabilise, which I think was Paul Coneely's contention a couple of weeks ago and is certainly something Dave Smith has maintained; Newtons third withstanding. I suspect the answer is by firing muscles when the leg is in open chain, but we'll leave that for another day... "pulling versus pushing revisited, yet again". -
Re: Podiatrist Recommends Forefoot Striking Versus Orthotics for Treating Running Injuries
Eric -
Re: Podiatrist Recommends Forefoot Striking Versus Orthotics for Treating Running Injuries
We move by the muscles generating motion at joints. Example: In stance, when the calf muscles contract, they create a plantar flexion moment at the ankle. When the ankle plantar flexes the center of mass of the body will rise and there will be an increase in ground reaction force on the foot that will accelerate the body upward. Yes, there will be a lot of internal equal and opposite reactions. The key to understanding and explaining the motion is in the steps of free body diagram analysis. First define the body and then examine the forces acting on the body.
Eric -
Re: Podiatrist Recommends Forefoot Striking Versus Orthotics for Treating Running Injuries
The result posted could be possible with the use of the longitudinal axis of the foot instead of the STJ axis. That's the problem with assuming the axis of motion is the long axis of the foot.
Eric -
Re: Podiatrist Recommends Forefoot Striking Versus Orthotics for Treating Running Injuries
Sorry, I think in a previous post I should have said internal moments and not external. -
Re: Podiatrist Recommends Forefoot Striking Versus Orthotics for Treating Running Injuries
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Re: Podiatrist Recommends Forefoot Striking Versus Orthotics for Treating Running Injuries
but the moments created by the contraction of the tricep surea ( internal plantarflexion moments ) does not mean the external dorsiflexion moments acting on the forefoot need to be equal and opposite. -
Re: Podiatrist Recommends Forefoot Striking Versus Orthotics for Treating Running Injuries
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Re: Podiatrist Recommends Forefoot Striking Versus Orthotics for Treating Running Injuries
I did have a small discussion with Eric about net moments and acceleration, and the thing that stuck was Eric saying that they will be equal and opposite unless the joint is under acceleration
1. I could not find the discussion
2. I could be wrong with what I remember Eric wrote
3. I am just wrong all together. -
Re: Podiatrist Recommends Forefoot Striking Versus Orthotics for Treating Running Injuries
Why can't you do it? -
Re: Podiatrist Recommends Forefoot Striking Versus Orthotics for Treating Running Injuries
why ? where does the dorsiflexion forces come from - GRF - therefore the ankle joint plantarflexers are able to overcome the dorsiflexion forces ( GRF ) without the help of other muscles etc , the result is no kinematic change ( no acceleration ) but there has been a change in where the net forces come from on the plantarflexion side and probably the dorsiflexion side as well, but mainly through an increase in external dorsiflexion forces acting around the ankle joint axis -
Re: Podiatrist Recommends Forefoot Striking Versus Orthotics for Treating Running Injuries
I can but it is harder than I thought
Tim -
Re: Podiatrist Recommends Forefoot Striking Versus Orthotics for Treating Running Injuries
of course they must be equal and opposite at all time :eek:
the change in axis position defines the point at which the forces on either side would be for them to be equal and opposite.
so we have acceleration ie kinematic change during this process the axial equilibrium position will change so that the forces are always equal and opposite, the change is the make up of the net forces on each side of the axial position.
the result kinematic change ie joint motion or acceleration will result in a new rotational axial position which defines the point at which the forces acting on the joint are equal and opposite.
sorry slow moment - pun intended
plus it means I need to rewrite a section -
Re: Podiatrist Recommends Forefoot Striking Versus Orthotics for Treating Running Injuries
When the ankle joint plantar flexes (motion and acceleration) there will be an anterior shift in the location of center of pressure of ground reaction force. This anterior shift in the location of ground reaction force will cause a dorsiflexion moment. If the plantar flexion moment from the muscle acting on the foot is greater than the dorsiflexion moment from ground reaction force acting on the foot then the foot will plantar flex because the net moment is not zero.
In stance, the tension in the achilles tendon can be gradually increased. There will be a gradual shift of the center of pressure anteriorly as it is possible to keep the net moment on foot at zero, for a while. At some point the ankle plantar flexion moment from the muscle will be greater than the ankle dorsiflexion moment from the ground and then there will be a net moment, at which acceleration will occur.
Some of the confusion occurs because we do a lot of free body diagram analysis when there is no motion. When there is no motion the net force and net moment has to equal zero. That is often where the equal and opposite confusion comes from. That is different than Newton's 1st law which is for every action there is an equal and opposite reaction.
Eric -
Re: Podiatrist Recommends Forefoot Striking Versus Orthotics for Treating Running Injuries
If I had a see saw and lifted up one end until the other end was in contact with the ground (i.e. the see-saw is now in closed chain) if I keep lifting up the free end it doesn't move any further, rather the ground reaction forces keep increasing at the contact point- isn't this the same thing? -
Re: Podiatrist Recommends Forefoot Striking Versus Orthotics for Treating Running Injuries
You can do it, if your calf muscle is strong enough, if you put your center of mass over the ball of the foot that you are trying to plantar flex. (Raising up on the ball of one foot is an excellent way to assess a patient's balance.) If you don't lean, then gravity acting on the center of mass and ground reaction force will create a force couple that will cause you to fall over, and people usually choose not to fall over.
Eric -
Re: Podiatrist Recommends Forefoot Striking Versus Orthotics for Treating Running Injuries
Eric -
Re: Podiatrist Recommends Forefoot Striking Versus Orthotics for Treating Running Injuries
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Re: Podiatrist Recommends Forefoot Striking Versus Orthotics for Treating Running Injuries
Eric -
Re: Podiatrist Recommends Forefoot Striking Versus Orthotics for Treating Running Injuries
I'm sure people can stand on their tippy toes, I'm just not convinced that they achieve it using the ankle plantarflexors in isolation which you've already conceded, Eric. Some other part of the body, which isn't in contact with floor has to move to enable heel lift or an external force is needed to jump start it- interesting. Cheers. -
Re: Podiatrist Recommends Forefoot Striking Versus Orthotics for Treating Running Injuries
Eric -
Re: Podiatrist Recommends Forefoot Striking Versus Orthotics for Treating Running Injuries
Eric -
Re: Podiatrist Recommends Forefoot Striking Versus Orthotics for Treating Running Injuries
But it still doesn't explain how the internal rearfoot plantarflexion moment ever overcomes the external forefoot dorsiflexion moment acting at the ankle. Yes the lever arm is finite but the ground can push back on the forefoot just as hard as the ankle plantarflexion moment can attempt to push the forefoot through the ground and the distance of the contact area of the foot distal to the ankle joint axis is much greater than the lever arm available to the Achilles . The harder the Achilles pulls the rearfoot into plantarflexion, the harder the ground then pushes back on the forefoot to create external ankle dorsiflexion moment. Both the external dorsiflexion moment and internal plantarflexion moment are limited only by tissue failure. So how is movement initiated; how is acceleration toward plantarflexion ever achieved at the ankle? My conjecture- not by the ankle plantarflexors in isolation. Rather it is initiated/ aided by muscles acting upon segments which are not in direct contact with the ground. -
Re: Podiatrist Recommends Forefoot Striking Versus Orthotics for Treating Running Injuries
Eric -
Re: Podiatrist Recommends Forefoot Striking Versus Orthotics for Treating Running Injuries
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