GB2428366A - Footwear to promote use of the fore-foot - Google Patents

Abstract

Modifications to the soles of footwear that will encourage and facilitate the use of the fore-parts of the foot as opposed to the heel for both body weight bearing and ground strike during walking. This is achieved by having either, as in the first embodiment, the greater thickness of the sole (a) or, as in the second embodiment, the whole of the sole (e) to lie under the fore-parts of the foot. The thinner rear part of the sole is either, as in the second embodiment, non-existent Fig 4 or, as in the first embodiment, of insufficient thickness and rigidity (b) to provide any degree of uplifting support to the heel, either by cantilever or by spring action, when not in direct contact with the ground.

Description

1 2428366

IMPROVEMENTS TO FOOTWEAR

This invention concerns modifications to the soles of footwear.

Nature has provided us with lower limbs each consisting of about thirty bones hinged by joints, held together by ligaments and acted upon my muscles and tendons. In other words a complex system of levers from hip to toe. It seems a little odd to me that, whilst performing one of our most common activities, walking, we lock the largest joint, the knee, so as to hold the long bones of the leg in alignment. We then take the impact of ground strike with the heel and allow the shock of that impact to be transmitted via the heel, up the long bones of the leg, through the ankle knee and hip joints to the pelvis. It is perhaps even possible that a small amount of residual shock manages to reach the spinal column. We do not allow the knee to bend until the other leg has taken up the burden of the body weight.

If a motor vehicle manufacturer produced a model of car with a pressurised hydraulic suspension system he would expect that system to be used in the way that it was designed to be used. If then subsequent owners of the model elected to de- pressurise the suspensions, allowing their cars to trundle around on their hard rubber bump stops, it would be highly detrimental to the structural integrity of the cars, not to mention their passengers and I would think that the manufacturer would be very annoyed. Yet it would be a situation very much analogous to the way in which we use our lower limbs. We were designed with a sophisticated suspension system but we prefer instead to stomp around on our hard bony bump stops, or heels.

I think that this is the underlying cause of some of the most common bodily disorders affecting human beings today such as painful heels, knees, hips and spine and poor muscle tone and circulation of the lower limbs. Anyone with an interest in sport will be well aware of the problem of the torn hamstring. This is an injury to which many of our strongest and fittest athletes succumb all too frequently at moments of extreme exertion on the track or field. These sporting activities are thought to be modern societies substitute for the far more serious and life supporting activities that our early ancestors had to perform in order to compete for food, or indeed to avoid being the next meal for larger predators. How successful would we have been as a species if they had been prone to the same disabling injury? That we are here today as the dominant species perhaps suggests that they were not, and the reason for this I believe is that they would have had much more powerful lower limbs.

I do not think that our earliest two legged ancestors would have used the heel as first ground strike point as much as we do today. Many people suffer from pronation of the foot. This is, put simply, a condition whereby the heel, upon striking the ground with the full force of body weight, rolls inwards stretching ankle ligaments and, because of the shape of the ankle joint articulating surfaces, causes an inward rotation of the tibia, which results in heel, knee and even back pain. It has been suggested that as early man walked, his heels sank into the soft earth and that this avoided the problem of pronation, but early shore dwellers, who could conceivably have been the first people to use the heel for ground strike, could not have hoped to have sand under their feet at all times, and much of the ground upon which even they walked would surely have been too hard to allow any significant amount of heel sinkage to take place. To have used the un-protected heel as first strike point on such ground would have put the walker at risk of painful injury, especially where the ground was stony, and the odd stone can crop up almost anywhere, perhaps hidden from view amongst the grass.

I believe that early man would for the most part have trodden a little more carefully than we do today, making greater use of the fore-parts of the foot for ground strike and weight bearing. This would have involved much greater muscle activity but would have broken the direct line of body-weight to ground transmission, greatly reducing the risk of first strike point injury and avoiding altogether the problem of pronation of the foot. The muscles of the lower limb would have been fully exercised, there would have been full utilisation of the shock absorbing capacity of our lower limb suspension systems and all the extra muscle activity would have helped to maintain the circulation in healthy condition.

However, using the heel as first ground strike point and treating the legs rather like a pair of stilts as we do today offers great energy savings so did our early ancestor alternate his choice of first strike point to suit the type of ground upon which he found himself? Where the ground was soft and therefore more energy sapping he could have been a heel walker, the soft earth preventing heel injury and foot pronation and where the ground was harder or more stony he could have been a fore-foot walker avoiding heel injury and foot pronation altogether. Of course knowing of man's fondness for saving energy, especially his own, I suspect that he would have preferred to be a heel walker wherever ground conditions allowed. This could have been the motive behind the invention of footwear, which would have provided the necessary protection to allow heel walking on the more punishing types of ground.

Footwear would over time be improved and developed to provide ever greater levels of comfort and protection for heels, a process much advanced in more recent times, and our use of the forefoot as a first strike point would become a thing of the past.

I have implied that it was natural laziness that made us over reliant upon the use of our heels for ground strike purposes, but is there perhaps another explanation? When the barometer reads high we are ever so slightly lighter than when it reads low.

This is because the denser high pressure air is more buoyant than the low pressure air. The received wisdom about the very early earth was that it was an extremely hot, dry and turbulent place. But recent studies of zircons, hard crystalline pieces of rock and the oldest things on the earth, have suggested that the infant earth was not as hot as previously thought, although still hot, but that there was a lot of water, contained as vapour in a dense steam atmosphere which would eventually condense as cooling took place to form the oceans. This would have greatly reduced the density of the atmosphere, but what if atmospheric density were already reducing due perhaps to the expansion of the universe? By making water molecules heavier, this could have been a trigger, alongside cooling for the precipitation which formed the oceans. As it is thought that the universe is still expanding, wouldn't the density of our atmosphere still be reducing making not just water molecules but us and everything around us heavier, albeit so slowly as to be indiscernible over a life time? Could this be what set us back on our heels? Apart from helping to explain some of the mysteries of the ancient world, this could perhaps be a factor in the extinctions of species. It has been suggested that perhaps as many as 99.99% of species that have existed are now extinct and that extinction, far from being an unhappy accident of nature, is the norm. Perhaps for species to survive they have to be able to adapt to ever increasing weight and even then for most, in the longer term, succumb and perish. Downsizing might be one way of adapting. The Book of Genesis tells us that before the flood there were giants upon the earth who lived for around 900 years, but perhaps they were much lighter than we are today. One of the oldest known species of complex organism is the millipede, early fossil examples of which show it to have been much larger than it is today. It also, as it's name suggests has many legs upon which to bear it's weight. We, on the other hand, being bi-pedal, have just two which I would think is a bit of a handicap whether or not weight is increasing. Even a quadruped like a horse is much better equipped to bear it's weight and if we look at it's hind legs in particular, there is considerable angulation between the different sections of the limb. In other words it uses its suspension system correctly.

What my invention tries to do is to restore to us what I see as the lost benefits of proper leg and foot function.

Most forms of footwear today have a sole which raises the foot towards the rear by incorporating a greater thickness of material under the heel than under the fore-parts of the foot, making it difficult to avoid putting the heel down first. Even with a flat sole I think that the majority of us would still put our heels down first. Therefore, what I propose are modifications to the soles of footwear, which will encourage and facilitate the use of the fore-parts of the foot for body-weight bearing and as first strike points during walking.

There are two embodiments of my invention which will be described with reference to the accompanying drawings. Figures 1, 2, 4 and 5 show the medial aspect of the right foot. Figures 3 and 6 show the plantar aspect of the right foot.

The first embodiment is a full-length sole as shown in Figure 1, having the greater thickness of material [a] to lie under the fore parts of the foot. By foreparts of the foot I mean the heads of the metatarsal bones and all parts to the fore of these. As the mid-arch plantar aspect of the foot is not particularly suited to weight bearing, I do not envisage that the greater thickness of material would extend rearwards beyond about half-way along the metatarsal bones, but this would be for future trial and experiment to determine. Essentially it would not extend to beneath the calcaneum. The rear, thinner part of the sole [b] would be of insufficient rigidity to provide any significant degree of uplifting support to the heel either by cantilever or spring action and would have sufficient flexibility to allow the heel to alight for rest purposes as shown in Figure 2. Its function would be merely to protect the heel and to provide a means of closure to the underside of the footwear. The rear edge [c] of the thicker fore-part of the sole may or may not need to be tapered or feathered [d} in order to avoid an abrupt edge which might cause trauma or discomfort to the mid plantar aspect of the foot.

The second embodiment would probably be more suited to a lighter type of footwear.

It would consist of just the fore-part of the sole [e] as shown in Figures 4 and 5 and would be held in position under the foreparts of the foot. This could typically be by its attachment to straps extending over parts of the foot and around the back of the heel, as in the sandal, or simply to the material of the upper parts of the footwear continued around the underside of the foot as in, for example the moccasin. It may even be possible to have a disposable or re-cycleable version for short- term use which could have a skin-friendly adhesive top coating for direct attachment to the bare foot.

Once again optimum rearward extension of the sole would be for trial and experiment although, as with the thickness of the sole in both embodiments, and the difference in thickness between the fore and aft parts in the first embodiment, personal preference and fashion might play a part. As in the first embodiment, the rear edge [c] of this shorter sole may need to be tapered or feathered [d]. Figure 5 merely shows an alternative way [1 of tapering the rear edge of the sole which may or may not be more comfortable for the wearer. You will note that the rear edge of the thicker fore- part of the sole in Figure 3, and of the shorter sole in Figure 6 have been drawn to a curvature [g]. This is merely to follow the curved line of the metatarsal bone heads.

A straight rear edge might serve the purpose just as well, especially if it were to be extended rearwards beyond the mid-metatarsal region.

Wearing this modified form of footwear would represent quite a drastic change in our way of walking and it may well be that older generations might find it too strenuous.

YoungergenemUonshoweveroughttobeabflJa fta Ithinktheoneswho would benefit most might be the very young taking their first steps and future generations.

Claims (8)

1) A sole for footwear that encourages and facilitates the use of the forepart of the foot for both the bearing of body weight and initial ground strike during walking.

2) A sole as claimed in claim 1, having the greater thickness of material to lie under the fore-parts of the foot, that is to say the heads of the metatarsal bones and all parts to the fore of these.

3) A sole as claimed in Claims I and 2 in which the rear part of the sole when not in direct contact with the ground is of insufficient thickness and rigidity to provide any significant degree of uplifting support to the heel either by cantilever or spring action when the foot is in weight bearing.

4) A sole as claimed in claims 1, 2 and 3, having the thinner rear part of sufficient flexibility to allow the wearer to alight the heel for rest and balance purposes.

5) A sole as claimed in claim 1, consisting of just the part of the sole which underlies the fore-parts of the foot, the rear part being dispensed with.

6) A sole as claimed in any of the other claims, being constructed of disposable or recyclable material, for short-term use, and affixed directly to the bare foot by means of a skin-friendly adhesive top coating.

7) A sole as claimed in any of the prior claims, having its rear edge as in claim 5, or the *1O* rear edge of the thicker fore-part as in claims 2 and 3, reduced gradually in thickness by tapering or feathering of the material.

8) Soles for footwear substantially as described herein with reference to Figures 1-6 of the accompanying drawings.