SCIENCE DAILY / “I am 53 years old and, since I reached my adult height, I’ve always worn shoes size 10. But now it seems that 10’s are become much too small. At the shoe store, an employee measured my feet and now I have to wear 12. So I wonder : is it possible that my feet have grown since the last two or three years, or is it that the sizes of shoes have changed ?”, would like to know Daniel Hurtubise, Gatineau.
Indeed, it is possible that the scales are not the same for all shoes. “Since the footwear is done a lot in asian countries, sizes are not universal from one country to the other. This makes it so a size 8 in one brand may be equivalent to a 9 in another, and may also explain the change in size over time,” says podiatrist Trevor Lamontagne, Health clinic, Podiatrist, in Quebec city. But this is not the only possible explanation.
Contrary to popular belief, tough effect that the feet grow throughout life, they cease actually to grow at the same time as the rest of the os, around the age of 22 years at the maximum. And like the rest of the skeleton, they will not return never more to be “pushed” by the result. However, it does not mean that they don’t change ever.
We have all beneath an “ark” more or less pronounced, in which to pass elastic tissue which act in the manner of a spring. When you put the foot down in walking or running, the arch will “expand” slightly, stretching his ligaments. This has the effect of spreading the load over the entire foot, absorb shock and store energy and then reuse it to continue to move forward, when one lifts the foot. In the end, this little game makes our travel more efficient, more economical from an energy point of view, read it in an article in “classic” on this subject published in 1987 in the scholarly journal Nature.
But lo and behold, said Dr. Lamontagne, “with time, the soft tissues of the feet can change and bring about a collapse of the arch of the foot, which can lengthen and widen. The bones do not lie not, but the collapse of the arch leads indirectly to the foot to lengthen”. In other words : if the ark “unfolds”, then the foot will become necessarily longer.
In addition, the weight gain (which sometimes comes with age) can accelerate the phenomenon. This “leads to extra stress on the plantar fascia, the ligament that maintains the arch of the foot, and this may contribute to accelerate the subsidence of the plantar arch,” explains Dr. Lamontagne.
As it always happens with individual cases like that of Mr. Hurtubise, it is not possible to say with certainty, since Dr. Lamontagne had not considered, but one can imagine that the”elongation” of her feet is simply the consequence of an ark which eventually collapse, for one reason or another.
Interestingly, adds the podiatrist, to have the “flat feet” (because of an ark set, or which is naturally very shallow) is not as serious as you think. “The flat foot has long been seen as problematic, she said. This comes among other physicians of the army in the early 1900s who observed that the majority of the soldiers who had pain in the feet also had flat feet. They have, therefore, hypothesized that the flat feet were the cause and explained this pain. Several soldiers then refused a place in the army because of it. […] In reality, the foot type is not a limiting factor for physical activity, whether it is flat or hollow. The feet will typically adapt very well to the chosen sport as long as the exercise is done in a gradual manner. The too rapid increase in the volume and intensity of training are more critical factors to control to prevent the risk of injury.”
Having flat feet is not ideal either, mind you, because it implies that the “spring” of the foot is not as effective as it could be. “Muscle fatigue created by the physical effort can then be increased to maintain the same dynamic in sports, said Dr. Lamontagne. The body demands more energy to a flat foot for the same effort. The collapse of the arch of the foot does not cause injuries to speak of, but may be a predisposing factor.”
This will not happen necessarily to all those who have flat feet, she says, since many people of which the arch is collapsed would never feel discomfort. But in case of pain (which can occur in the foot, but also elsewhere in the legs), it is best to consult a podiatrist, ” she said.
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