Knowing if the shoe fits

How big are your feet?

Mine are size 111/2 and I've always thought that was pretty big. So, regular-sized socks are out. Also, my slippers look massive.

But it also means that I can always find shoes of my size during a sale. Which explains my sizeable collection of shoes - much to the chagrin of my wife.

Then, a month ago, I discovered that what I knew about my shoe size has been wrong all this while.

Asics, a Japanese sportswear brand, recently opened a new store at Suntec City Mall where it has a complimentary Foot ID System that anyone can use to measure the size of their feet.

As the official party line goes, the system "evaluates data on two distinct levels, taking a two-fold approach to help runners make an informed decision, based on their personal foot specifications, to find the right Asics running shoe".

You're right. I, too, rolled my eyes when the invitation landed in my inbox.

Measurement has always been simple. You put a foot, sans socks, on a Brannock Device and a salesperson measures the width and length of your foot and tells you what size to try.

But I had never given much thought to the fact that "my size" varies so much between brands and even among shoe types.

I usually wear size 11 for dress shoes. But a size 11 sneaker is often too tight, so I go for 111/2 just to be safe. After all, how hard can it be to tighten the laces if the shoes are loose?

Any variation in size had to be due to the different cuts, or the thickness of socks I wore.

The Asics Foot ID System scanned both my feet and pronounced me a size 101/2.

I put my feet on a glass panel and a scanner produced a 3D model of each foot, not unlike a topographic image of a mountain.

Can science be wrong? The system decreed I should wear size 101/2.

The staff at the shop agreed that differences between brands could mean it was possible a size 11 would also fit me.

But wearing size 111/2 or, worse, size 12 shoes, which I have been known to buy, should be out.

So, when I tried the size 101/2 Asics Gel-Kayano 21 and my feet felt like a xiaolong bao or dumpling between chopsticks, I was sure that I was really a size 111/2 - just as I had thought all along.

When blisters appeared on my dumpling, I mean, my foot, I was ready to dismiss the Asics Foot ID technology. Until my wife suggested I loosen the laces.

I scoffed at the idea but loosened them anyway. It has now been a month and no more blisters have appeared. And I am very happy with my size 101/2 shoes.

I also loosened the laces on a pair of too-tight size 11 shoes and I can now wear them comfortably.

Have I been so dumb that I didn't realise I was wearing the wrong size all this time? Can I use this as an excuse to buy myself a whole new shoe collection? I wish.

Sizing is only part of the process of finding the right shoe. The Foot ID System also used cameras to record my running posture, the way my legs moved and how each foot landed.

I now know how to improve the way I take each running step, as well as the way I land.

I have been making a conscious effort to correct my running with my new shoes, and I plan to return for another round at the store to see if I've improved.

Maybe these shoes are not for you. Perhaps you will feel obliged to buy a pair after taking the test.

But the technology exists and the test is free. And you owe it to your feet to find out if your shoes really fit.

A version of this article appeared in the print edition of The Straits Times on June 17, 2015, with the headline 'Knowing if the shoe fits'. Print Edition | Subscribe