I'm a big fan of doing faster workouts in racing flats—lightweight, low-profile running shoes designed for road races. The light weight allows you to go run faster, and the lower heel-to-toe differential gets your ankles, calves, and Achilles tendon used to working through a broader range of motion. This can help prevent lower leg injuries and calf soreness that can crop up when you do a longer race in spikes.
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You can see creases from the crumpling |
Partially thanks to the now-fading minimalist
movement, racing flats have gotten a lot lighter and lower to the ground over
the past several years. While this is
great from a performance perspective, the drive for ultra-light shoes sometimes causes design flaws to be overlooked, and this can ruin an otherwise-great shoe.
I've been wearing New Balance's RC5000 flat in
track workouts and road races for about nine months now, and overall, it's been
great. But recently I've had problems
with the shoe's insole crumpling up under my toes. Usually, if a racing flat has an
unusually-thin insole, as the RC5000 does, it is glued down so this does not
happen. This is the case with virtually
all insoles in spikes as well—having a flap of foam or fabric peel up under your forefoot
during a race or workout is extremely irritating. But New Balance either chose not to glue it
down, or used an inferior glue that can't withstand the stresses of fast
running.
In any case, I decided to glue the insole back
into the shoe so I could keep using these flats. I contacted New Balance to see if they had
any advice on what adhesive to use, but their response, quoted below, wasn't
particularly helpful:
We don't recommend gluing your insoles in
your shoes. We make our shoes with removable inserts to allow you to further
customize your shoe fit through the use of our upgraded insoles or your own
orthotic. You can try another type of insole, such as Dr. Scholl's. Another
idea is trying a different lacing method to keep your insoles from moving
So instead, I did some research. Surprisingly, there is not much on the
internet about how to fix a running shoe insole that's peeling or crumpling up
under your foot. I've used Super Glue
(cyanoacrylate) to fix a peeling insole before, but that was on a pair of Nike spikes with a flat, smooth surface immediately underneath the insole. The bottom of the New Balance
flat has a mesh overlay, visible above, and I suspected that Super Glue would not adhere very
well to it and could potentially leave hard lumps under my feet. So that wouldn't do. I considered a number of other adhesives,
like contact cement, epoxy, and barge glue, but they didn't seem like good candidates: they either dried into a hard, brittle substance, cured nearly instantly, or wouldn't work well on foam EVA and fabric.
I settled on using Shoe Goo, a polymer adhesive that hardens into a
strong but flexible rubbery substance after curing for several hours.
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Supplies laid out—use newspaper to save yourself a mess |
The actual repair process was pretty simple. After making sure the shoe and the insole
were clean and dry, I applied a thin layer
of Shoe Goo to the outer edge of the insole's forefoot (highlighted in the
photo below), flattening out the glue bead with the shaft of a Q-tip—I didn't
want to use any adhesive under the weight-bearing area of the insole in case
the glue left any lumps or hard spots. That wouldn't feel too great on the sole
of your foot during a race!
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I only put glue in this area, avoiding the weight-bearing areas on the sole. |
After waiting for three minutes for the glue to firm up a bit, I put the insole back into the shoe, making sure not to get any
Shoe Goo on the upper and being careful to get the insole alignment right.
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Unlaced the shoe for easier access to the forefoot |
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Keeping the insole flat for glue curing |
I had removed the laces entirely so I had an
easier time getting the insole inserted into the forefoot of the shoe. Using my fingertips, I pushed down hard on
the edges of the insole to squeeze the adhesive into the mesh, and to smooth
out any creases or bumps. If the glue
holds, there's no do-over with this! Fortunately, Shoe Goo doesn't fully cure
for several hours, so you can fix any mistakes if you're quick about it.
To make sure the insole did not peel up, I
re-laced the shoe and stuffed it tightly with newspapers from forefoot to
heel. I let it sit this way for two days.
Today I took the repaired flats for a spin at my
high school's 2-mile cross country alumni race on wet grass with some tight
turns. So far, so good: even though the shoe got quite wet and I ran pretty hard in it, the insole feels
secure in the shoe, and I had no issues with peeling or crumpling during the
race! I also didn't feel any lumps or hard spots where I put the glue after it cured. I'll update this page if I have any problems
in the future.
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All done and holding up great! |
It did! I used the shoes for all of my faster workouts for several months without any problems with the sole again.
ReplyDeleteThanks good article i am having same issue by the heel on the side my soles are folding down.
ReplyDeleteWhere do you get shoe goo?
ReplyDeleteI think I got mine at Walgreens or Ace Hardware. Surprisingly easy to find!
ReplyDeleteThanks, this is the only post of this kind I can find on the Internet. I'm going to try the same with some basketball shoes.
ReplyDeleteAs a side, since I see you like minimalism do you have an opinion on the Vivo training shoes? I have a pair I intend to put a lot of miles on but I'm not sure if they will hold up to semi-serious or workouts. It seems they are a bit more form than function but feel amazing in contact with the ground.
Thank you John Davis! Glueing my shoes as you suggested!
ReplyDelete