Technical footwear fitting.
So you want to get fit for an adventure. You'd like to run a marathon or hit the Camino de Santiago or tackle the Appalachian Trail. You need to gather up some useful equipment; nothing too extreme just good quality bits and pieces that make life a bit more comfortable and ease your path to perfect, or near enough perfect performance. Out on the hill/road/track you find that the wicking baselayer does what it says on the tin. The waterproofs keep out the rain and wind and the backpack carries all you need without chafing. In fact everything seems just tickety-boo apart from your feet. Short sessions are no problem but long runs, steep descents or multi-day trips leave your feet feeling like they did ten rounds and lost to the heavyweight champion. Black toenails, blisters, calluses and general tenderness seem like an ever present problem. The enjoyment of the trip would be so much greater without this discomfort.
If any of the above sounds familiar then I would suggest that this article is worth a few minutes of your time.
Almost all of the problems listed above are the result of poorly fitting footwear and a limited understanding of what constitutes a good fit even amongst those retailers of sports and outdoor footwear who regard themselves as specialists. Even in the best stores some members of staff are better than others and so outcomes can be a bit hit or miss depending on who you encounter when you walk through the door.
What I would like to do here is give you a template or system to work with so that you have a clear idea of what to look for and have tools to evaluate the fit and make an informed judgement on how well a piece of footwear suits your foot. It is a bit geeky but I have been working at this business for well over thirty years and am now comfortable with being one of the “Shoe Nerds”.
I first got involved in this field as a ski instructor when I started suffering the negative effects of stuffing my feet into really unyielding, tight fitting boots for about two hundred days a year. In common with almost everyone in my position I could talk a good game about ski boots whilst knowing virtually nothing of value about how they should fit or how to change the fit to suit my specific feet. Off the slopes my interest in running and triathlons meant that the abuse of my poor feet continued unabated through the summers. For a while I was one of the post-marathon runners pulling my toenails off with my socks at the finish line. Eventually I started to find people who could show me a way to solve my own problems and then those of other people. Over the last few decades I have fitted people for all manner of shoes and boots for events as diverse as the Gobi Desert marathon, the Marathon des Sables, Denali ascents, the Olympic slalom in Whistler and Disney on Ice (Frozen). If you have problems then console yourself with the thought that at least you don’t have to cram your be-bunioned feet into a pair of ice skates whilst dressed as Olaf the snowman.
Start With The Feet.
This might seem obvious but it almost never happens. More usually people stand in a store looking at a wall full of shoes and either the customer or salesperson grabs one or two options to try on. The decision is often based on visuals, or third party recommendation or price. The items tried may be utterly different in volume, width and shape. Don’t waste your time on random hit and hope. Implement a more targeted approach. Don’t look at shoes until after you have checked out the feet.
A fairly small number of adults have had their feet measured recently. For a lot of us foot measuring ends as soon as mothers stop buying our school shoes. Given that our feet change gradually all through our lives and in the case of pregnant women quite drastically in a short space of time we should do more to keep up to date with our actual measured shoe size. It is really unlikely that any given human fits the same shoe size in their forties that they took in their teens. Feet change. They change size. They change shape and they change strength. Try not to be too dogmatic about what size you take. As Mark Twain never said “It ain’t what you don’t know that gets you into trouble. It’s what you know for sure that just ain’t so”.
As well as this, production tolerances and last changes mean that shoes often show significant differences even if the size is nominally the same. I once measured the inside length of seventy four pairs of UK size eight sport and hiking shoes. It was a slow day in work. There was a size difference of more than 11mm between the smallest size eight and the biggest. One brand alone had a difference of 6mm between their smallest and largest size 8s. Bearing in mind that a UK size is roughly 8mm this is a massive difference. It means that an eight can be smaller than a seven or bigger than a nine. The size on the box is only a starting point.
The classic Brannock device has been around for nearly a century and is still the most useful measurer I have come across. High tech laser scanners and measurers have come on the market but generally don’t add anything bar a sense of theatre and a pretty hefty price tag for the shop. One laser device is sold as being able to measure foot length to an accuracy of a thousandth of a millimetre. Given that a half size in the US Men or UK standard is roughly 4mm this seems unnecessarily precise. Note that there is a difference between a foot measurer and a “Shoe sizer”. The former are exactly as described. They allow someone to measure the length, width and arch length of a foot as per a given scale. Shoe sizers however are more brand specific. They allow a company like Clarks in the UK or Deichmann in Germany to put customers into the correct length of their own brand shoe. The size is unlikely to carry over well to many other brands however.
Width is important but marked width sizes are generally so unreliable as to be worth ignoring. The width of the foot is something that can only really be judged in concert with the volume and arch length. A big, fat, high volume foot with a high instep and a long arch length will require more space than a flat, wide foot with a short arch length. Arch length is the length from the back of the foot to the first metatarsal joint and is also known as the “Heel to Ball” length. Basically it should allow the wide part of the foot where the foot bends, to match the wide part of the shoe where the shoe is made to bend. Longer arch lengths mean that the wide part of the foot can end up being squeezed into the narrow part of a shoe’s toebox even in a wider fitting shoe. Ideally the aim is to have a situation where the heel and midfoot are firmly held in the shoe with minimal slippage whilst at the same time the toes are lost in space and can spread freely. This kind of fit will practically eliminate blisters, abrasion, callousing and bruising inside the shoe. Tight at the back, tight in the middle and free at the front. Best two out of three isn’t good enough.
Volume is probably the single thing that matters most after length. It is simply how much space there is inside the shoe. Often volume and width are equated but this is not always the case. Some narrow shoes have a huge internal volume which means that a narrow foot will still slide around. A broad shoe can have a low volume which suits those people with narrow heels, flat arches and a really broad forefoot. Think of these as being akin to flippers. A bulky high volume foot will need space to be accommodated properly. Too low a volume will mean extra pressure on the toes and the heel lifting out of the back of the shoe too easily causing excess wear. There is no standard measure for this but just look at your feet and see if they look bulky to you. If you have big feet you may have to move up through the sizes more than you expected. People with very slim, low volume feet tend to have fewer options. The correct length may feel really loose but the size down may have the toenails nibbling against the front of the shoe. It is important not to go too short or the toes will come under pressure but it is hard to find a lot of slim fit options in sports footwear. Volume adjusters and tongue depressors can be used to help fill up excess space but don’t suit every type of shoe.
Once you have a good idea of the shape and size of your foot then you can really get down to business with the shoes on the wall. If the salesperson knows their stock this should be very straightforward. If not you will just have to assess the footwear for yourself. Don’t be afraid to walk away and try somewhere else if you feel you need more informed purchasing advice.
High quality, functional sports shoes and boots generally have a removable insole. Before you put your feet into the shoe remove this insole and stand on it. With your heel at the back of the insole you should have about 10 -13mm of space ahead of your big toe. Skinny feet could get away with a little less length and high volume feet will need a little more but aiming for about 1cm will do well enough for most of us. The size of the insole is almost always the size of the shoe so this is a great little reality check to be sure that the actual size matches the numbers on the label. If your toe is right up at the front move up a size and if your foot barely makes it into the front half of the insole then move down in size.
Socks, Insoles and support.
The only part of the footwear system which is in direct contact with your feet. Good quality technical socks have to fill up space, cushion the foot, reduce friction and move moisture away from the skin as efficiently as possible. The best are made from wool, synthetic fibres or a mix of both. Wool is a great insulator and keeps feet warm even in cases of poor circulation. It is good at managing moisture at lower level activities such as hiking. Synthetics are better for short, high effort activities such as running. They can move a lot of moisture in a short space of time. Most performance socks are a blend of fibres all trying to find a comfort “Sweet spot”. All socks get saturated if the effort level is sustained and high enough. At this point it is worth switching to a dry pair if possible. Cotton is a more abrasive fibre, especially after washing and tends to hold moisture indefinitely. It is useful for such a short time in an active sense that it should be avoided for anything other than short walks. It is however much cheaper but you do get much cheaper performance along with the low price tag.
Supportive insoles can be useful in a couple of ways. For people like me with penguin feet they provide a bit of stability and prevent my feet from sliding around inside the shoe. This is especially important in something like an ultra-marathon event where fatigue will cause the foot to flatten further as the day wears on. For people with very high arches and more rigid, stable feet a decent insole will help spread pressure around the middle of the foot and away from the heel and ball areas. I have used many different options from very expensive custom orthotic devices to simpler, trim-to-fit over the counter insoles and have found a lot of good in both. What I have not found though is that the custom option is always superior. On the whole if you do not have a diagnosed medical abnormality then I would heartily recommend the cheaper trim-to-fit models. I really like Superfeet but Sidas, Sole and Hi-Tec all produce good options and it is a fairly crowded market. In this area there are no right answers. Suck it and see is the order of the day. If you get on better with one brand over another then that is the best one for you.
The one thing all of these brands have in common is a degree of firmness. Marshmallow doesn’t provide support and soft gel type insoles can increase foot movement inside the shoe so, for most people are not particularly effective.