I have had an interest in this topic for quite a while – well before the apparent barefoot trend took hold and the subsequent footwear / barefoot controversy ensued. I developed an awareness of the impact foot attire (shoes) can have on the function and subsequent health / injury status of individuals back as young runner in the late 1980’s. I realised the benefits for myself to start training in what is commonly known as racing flats (low profile running shoes) as opposed to the traditional robust, stiffer running / training shoe about 20-25 years ago... after a period where three types of injuries took hold - Iliotibial Band Syndrome, Shin Splints and Plantar Fasciitis. Putting aside some element of training error (i.e. insufficient adaptation to workload and insufficient conditioning of body to withstand the stressors) I realised that part of the problem had to do with the type of running shoe I was wearing.
I have known based on my own experience that the traditional structured running shoe with its elevated heel pitch (higher heel height in relation to forefoot height) is not an ideal element... as well as the myriad of advertised foot movement altering additions (alias motion control features / gimmickry) that has surfaced over the past 30 years - where the main advertised objectives has been to address “excess pronation” or out phase pronation and reduce “shock”... in an attempt to reduce injury rates. However, why have injury rates among runners remained consistently high over the past 30 – 40 years despite technological innovation in running shoe design?... from the basic flat running shoe of the 1960s through the myriad of motion control and cushioning innovations along the way – runners have been getting injured at similar rates regardless.
Tiger - Mexico 66 Asics - Kayano-17
Could there be another issue here which has slipped under the radar of a key assessment area? Could it maybe have to do with us... as well as the foot attire?
♦ Not as the musketeers say – "one for all, all for one"... at least on this topic:
I want to state at this point that this topic has many variable attributes associated with it which nullifies any “one for all” mindset when assessing the more appropriate foot attire for the vast array of individuals and hence vast array of runners on the planet. To carry this simplistic mindset into this topic will potentially lead yourself into problems and most definitely (based on probability) will lead others into problems. With this said, the topic does not need to be complicated. I will attempt to outline the basic principles needed to understand for yourself the need to put in the effort required to thus be a more efficient runner... whilst keeping in mind your body profile i.e. genetic makeup, biomechanics etc... However, if you don’t want to put in any degree of effort and / or expect a quick fix to your running related problems, then you will be disappointed. Unfortunately it tends to be human nature to gravitate towards little effort and subsequent quick fixes.
Whilst I get annoyed at the “one for all” mindset that seems to be expounded by some within the barefoot movement (i.e. shoes are no good – thus you should run barefoot or at least in “minimalist” shoes); let’s not also forget a similar mindset has been delivered to us running shoe consumers, not so much in words but certainly in actions via the implementation of structural characteristics dictated to us in a vast array of running shoes from across the running shoe manufacturing board (i.e. Adidas, Asics, Brooks, New Balance, Nike etc...). Structural characteristics of which, being an elevated heel height along with thick “cushioning” midsoles across the models (i.e. shoe name e.g. “Kayano”) and across the manufacturers (i.e. Asics). One can also suggest the “anti-pronation” or “pronation control” (motion control) characteristics but this is present in varying degrees depending on the category of shoe you buy.
In general, there are three main running shoe categories: “Control” (high range support), “Support” (mid-range support) and “Neutral” (mild to no support) i.e. shoes within the “Control” range will have more aggressive “pronation control”(motion control) elements, those within the “Support” range will / should have less, whilst shoes within the “Neutral” range should have little to no “pronation control” attributes... yet the vast majority (if not all) will have that elevated heel pitch & thick “cushioning” midsole across the board of categories, models & manufacturers.
♦ A False Rationale – Arch Type to Fit Pre-assumed Foot Function and Subsequent Shoe Prescription:
Now it should be stated at this point that there has been a false rationale behind fitting runners into shoes within the above three categories which has (and still is) been based on the shape of the individual’s foot print / arch type i.e. “flat, normal or high”. Shoe stores like the Athlete’s Foot usually use something like the following diagram to justify a shoe model to fit an individual’s lower limb function / biomechanics i.e. the “flat” (flexible) foot is assumed to always pronate (roll inwards) thus need more support / control; whilst the “high” arch (rigid) foot is assumed to always supinate (not roll in enough) thus needs more cushioning.
Putting aside the subjective nature of this “footprint” test, the actual individual results could be quite different to the speculated actions of the individual’s foot / lower limb movement. The foot print images are over simplified / generalised and can confuse people as to what is actually happening to them. For example, the underlying (plantar) surface of the individual's foot can either be 1mm off the surface or 10mm off the surface (i.e. the sensor pad) and thus could give exactly the same reading (i.e. a high arch profile), yet the dynamic function and structural alignment would present totally different results and subsequent symptoms... as well as subsequent footwear prescription i.e. a high arch footprint may not be indicative of a high arch foot structure and a high arch foot can be seen to pronate greater than expected. Thus a 2D image of this nature can not only give back limiting information but also give back contradicting information based on the stated advertised actions of these foot shapes / prints endorsed by some shoe retailers, running magazines, websites etc... thus another medium contributing to the spate of running injuries, that being - inappropriate shoe prescription.
♦ Shoe Structure:
So with what said so far, it should be noted that my main gripe with the traditional running shoe is the heel to forefoot pitch (i.e. heel height higher than forefoot height). Meaning, the heel height in the vast majority of models is way too high (some reported to be as high as 12mm difference) and this alone can potentially contribute to what I would like to phrase as an unnatural technique / form development – that being potentially exacerbating heavy heel striking and / or striking too far ahead of body (Centre of Mass i.e. hips, knees). Runners with this problem may notice a noisy / loud foot strike (i.e. foot slapping the ground) as they run. Foot strike should ideally be quiet as it makes controlled contact under the Centre of Mass (i.e. knees / hip) region of body. A good general principle to keep in mind is... loud foot strike = greater forces created (thus greater potential for increase stress to muscles / tendons and joints); quiet foot strike = less force created (thus better for reducing the chance of soreness and / or injury).
Frankly, the foot was designed to function on a plantigrade fashion (relative to the surface / environment). Hence, develop a shoe that reflects this – period! In my view the heel to forefoot pitch should ideally be at zero (0mm difference between heel height and forefoot height) or at the most 4mm – this should be an absolute across the board (no matter the category and model of shoe). The other two main attributes involve 1/“pronation / motion control” and 2/“cushioning”, attributes of which should probably be a variable factor (yet to milder degree compared to today’s shoe composition) across shoe models; quite simply because of the many variable body types, variable biomechanics (i.e. less than optimal lower limb mechanics), variable physical conditioning of individuals (i.e. being overweight)... factors of which are mainly based on and influenced by genetic attributes (i.e. the result of genetic entropy over the past 6000 years) and life style choices (i.e. poor dietary choices). That said, I don’t feel that “pronation / motion control” features should have the same degree of presence it has had in the past – if needed, this would be more efficiently addressed via a custom made device (an orthotic) fitted into a lighter, lower profile running shoe. On the other hand, for the optimally sound / efficient runner, a running shoe should really just serve as protection against the elements (i.e. non foot-friendly environment).
It should be noted at this point that “pronation” is not a bad thing – pronation is necessary to allow the foot to adapt to the terrain and to absorb shock. It allows this via the act of pronation to enable a more mobile / flexible foot (hence a better absorber at contact phase), whilst a supinated foot enables a more rigid foot (hence a better / efficient lever for push off phase). Thus it is an important design element to enable shock absorption via the foot at the first point in contact with the ground. To put the issue of forces into perspective; a runner of average weight (i.e. 65 – 70 kg) will potentially accumulate several hundred tonnes of force just over the course of 10km, thus the importance to address the shock of ground reaction forces as they are submitted to the body. Where pronation can become problematic is when the act of pronation is excessive (i.e. the degree of movement / rotation, which also includes the speed / velocity of this movement / rotation) and / or when pronation lasts longer than it should within the gait cycle i.e. still present at push off.
♦ Lower Limb / Foot Structure:
There should be little doubt now that poor footwear can lead to injuries (as well as poor form / technique). But what is “poor footwear” exactly. The issue here is what may be poor for one person may not be necessarily poor or as poor for another. With what I’ve said so far, I’ll admit that I personally consider the majority of sporting / running / casual shoes as poor based on the heel to forefoot pitch alone (a very frustrating position to be as a Podiatrist required to provide footwear advice to patients). But with this aside, people need to be educated on what attributes their body has and the potential repercussions thereof - of which could potentially influence their activity / running level... and hence their ability to run, get fitter, more conditioned and adapt to the desired workload – without meeting their injury threshold too soon (i.e. not falling victim to injury after just a week of training). The most important aspect is lower limb structure - which will govern lower limb biomechanics and subsequent movement / coordination along with subsequent forces directed to joints and soft tissues (i.e. muscles, tendons and ligaments). For example there are various structural characteristics which can influence foot function and subsequent lower limb function (biomechanics) and potential running efficiency. Basically, if someone has a foot structure which is not structurally sound then this will potentially increase the degree of forces being directed to various parts of the body of which the affects of this stress can then accumulate and lead to not only delayed onset muscle soreness (DOMS) but injury some time down the road. For example, foot mechanics which contribute to excess internal / medial lower leg rotation can adversely affect knee function or can affect tendon, muscle or fascia health i.e. the development of Plantar Fasciitis, Tibialis Posterior Tendonitis or Shin Splints. I will not get into the specific mechanics of foot / lower limb structure which can lead to adverse forces / stress and subsequent injury – only to say that the less structurally sound individual can potentially have more difficulty running to potential than the more optimal structurally sound individual. Now with the above said, it should also make sense that the less structurally sound can potentially have greater difficulties in running barefoot than another with more optimal lower limb structure. However, this is also influenced by another factor – body / lower limb conditioning i.e. the muscle / tendon strength and length... hence the next point.
♦ Body / Lower Limb Conditioning:
The next important aspect is body / lower limb conditioning. We all should aspire to become optimally conditioned individuals if we want to get the most from our bodies (i.e. good muscle / tendon integrity, strong core, good agility / coordination etc...) as this will help offset the chance of injury. In reference to the above paragraph, there could be a runner with less structurally sound biomechanics have a lower susceptibility to injury to another with more optimal biomechanics due to the fact that they are quite simply more conditioned i.e. stronger muscles / tendons with optimal range of motion at joints. Hence it is important for all to focus on studying this area and putting the principles to practice. I have outlined some principles in the “Exercises” and "Plyometric" sections of this website to get started and provide an idea of what is beneficial to help build optimal conditioning. The section includes plyometric exercises which also encompasses technique / form entrainment routines to help develop and activate key muscle groups to aid in stability (i.e. Glute / buttock group). Not to mention lengthening and strengthening those all important calf muscles (as well as Achilles) so as a lower heel pitch shoe can be transitioned to in the future.
- The following video is informative on this area...
♦ As Yoda said... "Unlearn What You Have Learned":
Put simply, the majority of individuals are just not conditioned appropriately to withstand the desired level of activity they wish (or are coerced) to partake in. Yet shoes have in the recent past now been blamed for the spate of running related injuries. Whilst this may be an influencing (i.e. secondary or tertiary) factor (to varying degrees from person to person) as a shoe could be contributing to excess forces i.e. eccentric loading forces (force directed to a structure i.e. muscle and / or tendon, whilst it is elongating). We also need to take responsibility for ourselves and look at the conditioning of our own bodies.
We need to unlearn what we have learned. After all, how many humans this day and age spend the majority of the day sitting (habitual sitters) in a chair which is contributing to poor upright bi-pedal conditioning i.e. tight hip flexors and contracted Hamstrings? Hence their running form usually reflects this! Some may have just started an exercise program and / or only play a running related sport over the weekend of which to find out that their normally sedentary unconditioned bodies are either too sore or have acquired an injury. There are some who may be somewhat experienced runners with a long history of injury which could quite well be all related to the one underlying cause – less than optimal lower limb structure / biomechanics... with associated less than optimal muscle / tendon integrity. This could have been exacerbated by poor footwear (i.e. higher heel pitch exacerbating the above mentioned eccentric forces) for the individual... but to then provide the solution as get rid of the shoes and run barefoot without looking at the holistic nature of the issue is just plain short sightedness – particularly when it is made as a blanket statement with no consideration for the individual traits of another (i.e. statements made in books, magazines and internet).
I feel running barefoot can potentially help many individuals as it does help strengthen / condition lower limb muscles / tendons. Another beneficial aspect is that running barefoot does help entrain optimal technique form development via reinforcing more optimal body positioning, limb and foot placement thus help reduce the adverse forces (which also entails reducing foot contact noise as mentioned earlier) which can potentially contribute to the commonly attained overuse type injuries i.e. Plantar Fasciitis, Achilles Tendinosis, Shin Splints, Patellofemoral Pain (Runners Knee) etc... The issues we need to keep in mind when delving into this topic should be that of a holistic nature... assessing the body, technique / form, foot attire as well as environment (i.e. running surface) – all of which are interrelated with each other.
♦ Enhance Performance:
When all is said and done – what about performance (i.e. running faster, achieving your personal best times etc…)… after all, many are interested in this (despite some within the barefoot movement). I have alluded to the possibility of increased performance via the potential improvement in technique / form which should help with efficiency / economy for many runners and also reduce the possibility of injury – thus potential increase in performance. Then there is the area of conditioning / strengthening the body for running via the implementation of drills / plyometric exercises as well as training in bare feet. These help strengthen the core and lower limb muscles which are important as most of the balance and proprioceptive sense we get comes from our muscles. Also conditioning of this nature helps develop the neuromuscular pathway (the communication line) from the brain to the foot (which is the longest and slowest in the body), thus improving this pathway will improve both coordination and response time. This along with better balance and proprioception; each foot strike and subsequent gait cycle becomes that little bit more efficient via reducing excess movement and instability… factors of which can accumulate to reduce lost time as well as reduce adverse forces that can lead to injury. If one can improve response time and efficiency at each foot contact (even by 1/100th of a second) then benefits of this should increase exponentially over the course of a training session or race which could well accumulate over the course of a 10km or marathon which potentially may well equate to many seconds or minutes gained via the improved foot function of the thousands of steps taken throughout the course of a training session or race.
Now as far as footwear is concerned, shoe weight can have an effect on economy and subsequent performances... but there are conditions. As already stated in the “Footwear” section of this site, research has indicated that barefoot running on the harder surface can be more costly (i.e. cost more energy to run at the same speed) compared to running with shoes. It is believed that this is because you have to use the leg muscles more to absorb the landing shock. However, tests have also revealed that each 100 grams (3.5 oz) of weight added to running shoes increases the cost of running (cost more energy to run at the same speed) by about 1 percent:
- (Franz, Jason R.; Wierzbinski, Corbyn M.; Kram, Rodger. Metabolic Cost of Running Barefoot versus Shod: Is Lighter Better? Medicine & Science in Sports & Exercise: Post Acceptance, 2 March 2012).
- (Morgan DW, Martin PE, Krahenbuhl GS. Factors Affecting Running Economy. Sports Medicine 1989; 7:310-330).
This equates to about 1 minute in a marathon and about 12-15 seconds over 10km. Thus, as the shoe becomes lighter, the cost was less; however, when the shoe was very light, the cost started going up again because very light shoes have limited shock-absorbing characteristics, so the muscles start having to work more (like with barefoot running on harder surfaces). Hence, it would appear that some element of cushioning is needed when running on harder surfaces as far as economy is concerned (known as the "cost of cushioning" hypothesis). For further reading on this topic, the following Runner's World article... Barefoot Vs. Running Shoes: Which Is (Surprisingly) More Efficient?discusses recent research on the area... Metabolic Cost Of Running Barefoot Vs. Shod: Is Lighter Better?
Thus the take home message is that appropriately conditioning the body to the act of running will improve performance as well as wearing the appropriate foot attire based on the intended running surface and activity.
The human body has been intelligently designed to run... with millions of interrelating processes working harmoniously together in symbiotic fashion for functioning as a whole unit... to potentially allow us to ambulate at speed over long periods of time, over long distances, over various terrains and environments... to allow us to find the rewards in the form of freedom, pleasure, health and fitness. No other creature on the planet possesses these attributes – we were Created from the start to run as is evident via distinct physiological traits unique to humans (Homo Sapiens)... we just need to reconnect to this source and rediscover our ability and purpose.
- The following video has some valid tips on... “The Principles of Natural Running”...