Spring is here and Dr Ivo Waerlop of The Gait Guys talks about some common problems seen due to manufacturers defects in cleats and how they can affect athletes. From uppers put on the outsole incorrectly and contributing to and potentiating rearfoot varus and valgus to poor cleat placement affecting the 1st mtp mechanics; they all contribute to athlete performance.
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Today’s Show notes:
Is a flexible forefoot varus foot type going to safely perform in a bladed soccer shoe or would it do better in a studded shoe ?
Recently an independent send us several pairs of revolutionary soccer cleats to get our opinion on them since we have somewhat of a history looking at and modifying cleats for NFL players.
Soccer is a unique game. During any one game players are expected to jog, sprint, run backwards, sideways, quick cut, cross over and many other variations. The soccer cleat is supposed to be designed to help the foot engage the ground to maximize and optimize these gait variations. A good cleat will enable and not disable or increase risk of injury. Accourding to some sources, a 90 minute professional soccer match can ask a player to run anywhere from 8000 to 11000 meters. One source suggested that two thirds of the game is walking or light jogging, One thirds is cruising, backing or sprinting and of the sprinting, 800meters requires maximal bursts of 10-40 meters over a total of approximately 800 meters. Obviously, it is these 800 meters that are the critical ones that can make a game and it is at these times that the player is likely to need a good reliable cleat-ground interface to perform.
It has previously been thought that the cleat cannot be too deep and ground-engaging otherwise torsional forces from the body will not play out into the turf and will rather move up into the ankle and knee and can lead to devastating injuries. However, one can make the case that a cleat could in some instances help to block excessive motion that could lead to injury. There are many grey areas when it comes to these kinds of issues. Cleat choice for the ground type and playing conditions seems to be important. However, a small study in 2007 (1) in the American Journal of Sports Medicine author Rajiv Kaila investigated knee loading patterns during various sidestep, cutting maneuvers and found no differences in the amount of force, stress or the degree of unwanted knee movement wearing any of the four styles of shoe. The study results were also backed by another similar study in the International Journal of Sports Medicine (2). The Gait Guys still remain somewhat skeptical however as these were unfatigued players and female players were not included in the studies as was suggested by this nice brief review article by Jay Williams. That being said, there are studies that recently exist that discuss landing mechanics based upon gender, footwear, and the mode of landing as notable issues in injury incidence so not only do we need to consider the shoe, but also the person in the shoe and how they land as additionally relevant parameters.(3) When we speak of loading and landing patterns there are many issues to consider, and foot type and cleat pattern are variables to consider. According to Queen (4) significant differences in forefoot loading patterns existed between cleat types. And when you put a forefoot varus or valgus forefoot type (and, one must know if that forefoot type is rigid or flexible, compensated or uncompensated) into a cleated shoe there are many variables that can play out. A forefoot varus is less likely to inversion sprain than a forefoot valgus foot type. Again, this is why we strongly recommend everyone take the National Shoe Fit Certification Program so that all of these variables can be taken into account.
When it comes to soccer shoes, comfort and fit are critical for performance. (One must also realize that just like in hockey, soccer (we prefer to say FOOTBALL but it is not the preferred name here in the USA) players like to drop a half to full size in the shoes so that there is less foot-shoe interface slide and give. Players like the foot and shoe to perform as one because of the precision foot work and sudden pivoting that is often necessary.) The issues of last shape are always critical depending on foot types. Just like in running shoes, a more straight, semi-curved and curve lasted shoes need to be matched to the appropriate foot types. We have talked about these issues many times before in previous blog posts here on our blog. Generically, a more pronated foot will get more control from a more straight lasted shoe and a more rigid-supinated foot will like a more curve lasted shoe. This is why you MUST know the foot types and how to determine what foot type your client presents with. This is why everyone should take the National Shoe Fit Certification Program. In this program we talk about the other shoe parameters like heel counter, sock liner, uppers, last patterns, vamp etc.
There are basically three types of cleat types, blade, stud. The choice of which to use is based on the surface of play and the conditions. The surfaces are broken down into 4 basic conditions: Soft ground, hard ground, firm ground (these are in decreasing order of ground “forgiveness”) and finally turf.
Turf fields generally dictate smaller more grippy finely studded cleats that enable maneuverability.
Hard ground fields will require shorter studs with generally a more uniform pattern and they are softer to react with the firm surface.
Firm ground fields require a longer more rigid cleat or blade. This is the most common cleat used. They can range from 10-15 cleats protruding from the outsole and can vary in depth and size. Pivot-mobility points, stability points are generally considered in determining number, size, depth and location of the cleats or blades.
In soft ground or wet conditions longer cleats are often necessary and they can range anywhere from 10mm to 20mm in depth. Some types of higher end shoes (usually professional level) allow cleat selection by screwing them into the shoes and this allows size and depth specificity. Cleat numbers can vary but are often much fewer (6-8) in number and location to offer even weight distribution. A more circular forefoot cleat/blade pattern supposedly optimize directional acceleration while more laterally and linearly arranged patterns supposedly provide more laterally oriented movements. This type of cleat should not be used on other surfaces as injury risk can increase.
There is much to consider when choosing a cleated football/soccer shoe. There is the foot type, the shoe last, the playing conditions, the cleat pattern etc. The more you know, the safer you may be.
Shawn and Ivo, The Gait (and shoe) Guys.
Influence of Modern Studded and Bladed Soccer Boots and Sidestep Cutting on Knee Loading During Match Play Conditions. Rajiv Kaila, MBBCh, MRCS, MSc*
Effect of Soccer Shoe Cleats on Knee Joint Loads.
Scand J Med Sci Sports. 2012 Apr 20. doi: 10.1111/j.1600-0838.2012.01468.x. [Epub ahead of print]