In addition to a sole that can expand horizontally on demand, there are a couple of other features of most (but not all) FiveFingers that also contribute to their comfort for wide feet. One is that the uppers are somewhat elastic or are made of a leather that stretches. This helps make it possible for the forefoot to widen as pressure is applied in pushing off. The final feature is something that I only began to appreciate with more recent models of Vibrams on which the feature has been altered. This is the stretchy panel on the outside of the big toe. When a shoe—any shoe—is stretched across the forefoot, the toe is pulled in. I discovered this a decade ago when I ruined an expensive new pair of mountaineering boots. I stretched the width to accommodate my wide forefoot and bunion, but in so doing the length was shortened to the point of being too short! With VFF, since the toes are largely independent, most of the shortening in focused on the big toe pocket. With the traditional VFF models that have the same stretch panel on the outside of the big toe as between the toes, the material stretches and all is well. The wide forefoot is accommodated and the big toe is left in peace. My first (and worst) encounter with a FiveFingers model that did not have a stretchy side panel on the outside of the big toe was with the Trek Flow (which is identical to the Flow except for use of the Trek sole). The outside and top of the big toe are covered with a transparent plastic film that does not stretch. As a result, the tips of my big toes felt like they were being crushed. I’ve avoided wearing these other than for one SCUBA dive. Initially I had a similar experience with the all-leather Trek LS. The tips of both big toes were bruised and the toenails blackened. But the ability of leather to stretch offered a solution. I cut the tips off a pair of shoe stretchers to match the angles of the open areas inside the VFFs. The shoe stretchers worked to make the VFF uppers wide enough to accommodate my forefeet. With this change, my big toes slipped into the toe pouches without any discomfort. These have become my favorite pair of VFF, which I wear to work every day. A week ago, with the arrival of a pair of the Spyridon LS and the SeeYa, I became aware of a change that Vibram introduced in the lace-up version of the Bikila — the Bikila LS (and about the same time in the Trek Sport and the Kommodo). All of these newer models run the upper fabric from the inside big toe pocket panel over to the outside of the big toe as one single piece. Gone is the separate stretchy panel of the same material as used between the toes. Since the material on the inside of the big toe is very stretchy, and the fabric on the upper is somewhat stretchy, they still feel comfortable. But visually the Spyridon LS was a shock. Half of my big toe was ballooning out – a bright orange balloon, looking like the wattle of a bird engaged in a courtship ritual. So you can see what I’m talking about, below are photos of my feet in various Vibram FiveFingers, as well as a couple thong sandal shots for comparison. From left to right, top to bottom you’ve got the Trek LS, Bikila LS, Bikila, KSO Trek, sandals, sandals, SeeYa, and Spyridon LS FiveFingers: You’ll note that the SeeYa and Bikila LS don’t balloon out nearly as much as the Spyridon LS, probably because the uppers are made of a more stretchy fabric. But they do balloon, somewhat. On a side-to-side comparison, I definitely prefer the balance of the standard Bikila to the ballooning on one side of the Bikila LS. Here’s an up close look at how the big toe pockets accommodate my wide feet (Bikila, Bikila LS, KSO Trek, SeeYa, Spyridon LS, Trek LS). The Speed (not pictured) is a somewhat different shoe because of the construction of the upper. The multitude of non-stretchy elements makes the upper less-stretchy in general than other Vibram FiveFingers. It’s the only VFFs in which I’ve had to go up a size. In the larger size, these have become my standby gym shoe for almost two years. I don’t need the laces for fit, but the laces provide an excellent support for the footpod that I attach to record my treadmill workouts. There you have it: why Vibram FiveFingers work for wide feet (and why some VFFs work better than others). It would be great to hear from anyone else who has wide feet and wears FiveFingers. If any manufacturers are paying attention, you might take note of the innovation Vibram has brought to the table with both their width-accomodating soles as well as the added stretching capacities provided by individual toe pockets.
A before and after side view of the extra sole that wraps up the side of the foot at the largest metatarsel; note how it can be pushed all the way to the table, thereby adding width to the sole.