I am frequently asked about shoes such as the MBTs or the Fit Flops – are they any good, will they make my bum smaller in this? Will they help me balance? Well, the problem is that they are shoes with thick soles, leaving us free to trot over broken glass or shingle with never a wince. We have absolutely no idea what is happening underneath our feet unless we walk over a big stone that makes our ankle tilt. And yes, this matters. I have just been reading a book called Balance, In Search of the Lost Sense by Scott McCredie. The book is extremely accessible and worth a read if interested in balance and how it affects out entire brain. In chapter 8, I came across an extremely interesting couple of paragraphs where McCredie is talking about the effects of thick-soled trainers upon balance. He talks about a study done in the early 1990s by Steven Robbins at Montreal’s McGill University on a group of elderly (65 – 83) and younger (22-37) subjects. They were stood on various angled blocks, either barefoot or while wearing the same model of thick-soled training shoe. They were asked to estimate the angle of the block. Barefoot, the elderly had an average estimation error that was 162% greater than that of the younger group. Not very surprising, really. However, clod in their trainers, both groups made even larger errors of judgement, the elderly increased their error rate by 28% and the youngsters by a whopping 103%. If the usual sort of trainer blunts the messages to the brain by so much, this cannot be a good thing, whether old or young.
I tried looking for this particular piece of research, but instead came up with another one by Robbins in which he was looking at the sensitivity of 3 parts of the sole of the foot – the middle of the heel, under the ball of the foot and in the middle of the bottom of the big toe. What he found was that the most sensitive spot is under the ball of the foot, and if we walk or run about in bare feet – or thin soled trainers, as we hit lumps and bumps, the discomfort in the ball of the foot inspires the small muscles within the foot to contract and strengthen the arch, as they should. And this causes us to transfer our weight forwards into strong toes. If the foot is cushioned in comfy shoes, this does not happen. So as we walk or run over our foot, although the pressure on the ball of the foot rises, there is no discomfort and the little muscles in the foot go to sleep and the feedback about what we are walking on and how it can affect our balance becomes poor.
When barefoot on natural surfaces (naturally deposited ground), sensitivity differences can be seen to induce behaviour that results in the transfer of forefoot load from the metatarsal-phalangeal joint [the ball of the foot] to distal digits [the toes], also changing arch support from unyielding musculature. Conversly, the lack of similar adaptations in shod populations is explained by the regular interior of modern footwear, which diminishes sensory feed back on weight bearing. This may result by direct trauma in osteoarthirits of the metatarsal-phalangeal joints in shod population and, indirectly (via augmented impact), in running-related injuried and perhaps osteoarthritis of the hip articulation.1
I also came across the page of the Society for Barefoot Living, who have a page of studies on barefoot vs shoes. The studies have been shortened so are readable.
The message is clear. Our feet can only help us balance if they can actually feel the floor underneath them. I suppose it is a bit like the difference between driving a basic Lotus Elise as opposed to a lumbering Chevy. One shoots about the corners, the other wallows about with the nimbleness of a sea slug. However, if thick soled shoes of whatever variety have been worn for a number of years, then we have to be careful about the transition to thinner shoes to avoid injury.
So yes, thin, flexible shoes – or no shoes – do help balance. But they aren’t the end of the story. To improve balance also involves assessing how the well the brain is connecting with its body and how well the eyes and inner ears are functioning. Sort out this lot, and the brain will work better overall. And we will bounce through an active, brainy life and on into our dotage.
- Robbins S E. Gouw G J. Hanna H M. Running related injury prevention through innate impact-moderating behavior. Med Sci Sports Exerc. Vol 21 No 2. ppp130 – 139. 1989 [↩]