Shoe Review: Pearl iZUMi Shoe

Pearl iZUMi syncrofloat IV

The Pearl iZUMi (PI) syncroFloat IV shoes that I'm testing look nice and feel fine. I wore them around the house for several hours to get a feel for them. There is one strange thing about them, though -- the heel. On the outside of the heel, toward the back of the shoe, there is an open space that is about 2 inches long, half an inch high, and an inch deep. The "floor" of the hole is the SkyDex heel crash pad, and the carbon-rubber covering the heel is on top of that, supported by several "pillars" that extend up from the crash pad. The shoes feel comfortable, so I assume this open space is part of the impact-absorbing design of the heel.

The shoe is described by PI as a neutral shoe, but the marketing description of the shoe admits it has a bit of correction. Most of the websites I visited list the shoe as a correction shoe. Here is the marketing description of the shoe.

If you’re an efficient runner looking to log your miles in comfort, the Pearl Izumi SyncroFloat® IV running shoe makes a smart choice. This men's running shoe offers the neutral runner supreme cushioning with a touch of stability. Cushioning in the heel and forefoot provide more energy return with each step and a smoother overall ride. The shock-absorbing SKYDEX® heel crash pad and the hybrid blown rubber forefoot/carbon rubber outsole ensure long-lasting comfort, traction and durability in the Pearl Izumi SyncroFloat® IV athletic shoe.

I'm using neutral shoes, because I supinate, and neutral shoes are recommended for runners who supinate. However, I have a normal arch, and that indicates I might need control shoes. I'm hoping the syncrofloat IV will satisfy both needs.

Pearl iZUMi recommends the shoes be 1/2 size larger than ones dress shoes, and that scheme is about right for my feet. There is about half an inch between my longest toe and the inside of the toe box but the shoe felt slightly lose (in width) last night, although I didn't feel any slippage of my foot inside the shoe . Today, during my run, the shoes felt "just right", because my feet increased in size during the run.

During the maiden run in the shoes, I ran/walked 5 miles, and the shoes felt fine. No blisters, no tender spots. No loose laces. I'll be wearing these shoes for several weeks and will update this review as I get more miles on the shoes.

2/19/2011 I've put 21 miles on the PI shoes and they still feel great. It rained the whole time I was running this morning, and after 2 hours, me feet were still dry and warm. That's good news! Another thing I was able to check this morning was how well the shoes performed on wet asphalt and concrete. I had no trouble at all with the wet path. Most of the path is asphalt, and the asphalt is naturally rough. However, there were a few places paved with smooth concrete, and that surface is more likely to be slippery when wet, especially one segment that was on a downward slope. I stopped midway down the slope and tried to slide my shoe on the concrete, to no avail.

2/28/2011 I conducted a "scientific" experiment to see how well the SyncroFloat repelled water on top of the toe box. I poured a teaspoon of water on the toe box. Most of the water ran off, and when I put my hand inside the toe box, I couldn't feel any dampness. This shoe should be good for wearing during rain or snow storms or running through rain puddles or slushy snow.

4/18/2011 Today's run was a great test of these shoes and water. I ran for 1 hour and about 45 minutes in rain and small puddles. When I finished, my socks were damp, but not more than one might expect after being in rain and drizzles for almost 2 hours. I didn't feel any water on my feet, but my socks were damp but not wet.

5/25/2011 After running 99 miles on the PI shoes, I've found no problems with them. They fit well and served me well. About half of my runs are running and half walking, and the shoes did well at both paces. My only complaint are the round shoe laces, and that is just my personal view rather than a fault in the shoes. I was worried the laces would come undone, but I double-knot them, and they stayed tied.

3/10/2021 I retired my iZUMI shoes today. They've given me 500 miles of good running. They will now be my walking shoes for non-running activities each day.