Under Armour continues to make improvements to its running shoe line-up. The Speedform Slingshot is their first trainer using a knit upper. We were super excited to try it out after visiting the team at UA earlier this year. Fritz gave us the deets on the shoe. “The upper is our first compression knit upper. The idea was to develop an upper that felt as lively and springy as the midsole. It is 3 dimensionally knitted with 3 zones of varying compression. The lateral side is a tight and springy compression, the medial arch area is the tightest compression with the least give and the forefoot is a bit looser compression to allow the toes to spread. The silver threads that wrap around the forefoot/ toe box are yarns called Dynema – super strong thread developed by NASA. We use them there to make sure the forefoot doesn’t move around too much with the looser compression.”
Thomas: The Speedform Slingshot looks like a fast shoe and delivers with a low profile snappy feel. Softer Charged® midsole foam is under your foot, a TPU (plastic) Y- shaped plate is sandwiched below the Charged® and firmer Micro G® midsole material. The combination of Under Armour’s Charged® midsole and Micro G® midsole materials works well to provide runners cushioning for either the runner that prefers to feel the road or likes a fast stable ride. The shoe lends itself well to fast turn-over with at a scant 8.25 oz. for a size 10.5, 8mm drop, and generous rubber on the outsole for grip add to the fun.
Meaghan: I was excited to try out the Speedform Slingshot after I heard that UA athlete, Nick Arciniaga, would be wearing them for the LA Olympic Trials. I’m always intrigued by shoe choices of the elite. Anyway… the upper is a knit burrito construction that hugs the foot like a sock. It’s designed with the same yarn used in the Under Armour tech tees and features woven in Dyneema. Dyneema is a super strong (think bullet proof vest) fabric that can be found in shoes like those fancy all-white Adidas Ultra Boost. It feels like a quality shoe. I’m sure this fabric has something to do with that. The upper also has three zones of compression; max on the lateral side, full on the medial side, and partial compression at the heel. There is a good balance of support and stretch. The midsole is constructed with a dual-density Charged® cushioning, Micro G®, and there’s a Y shaped Pebax plate running down the length of the shoe. The plate gives the shoes a slight bounce to a generally firm ride. There is a decent amount of rubber on the outsole which seems to help with traction and durability. I haven’t seen any real wear on them. The *best* part of the shoe? My W7.5 came in at 6.45 oz (!!).
Thomas: The fit of the one-piece upper isn’t quite dialed in. I have issues with heel lift in the Speedform Slingshot. While the burrito style wrap is an interesting feature, it is difficult to adjust the fit. Initially, I thought the other slits on the medial (instep) side of the shoe could be used as lacing holes to adjust the fit. However, there is no structural support like there is behind the holes with the lacing. The shoe wants to go fast but with the upper issues, it can feel a little sloppy. With a better fit on the upper, this shoe could be a real winner for me.
Meaghan: Much like Thomas, I had issues with the fit, particularly in the heel. Where you can normally adjust the lacing to help keep your foot in place, the burrito style lacing doesn’t allow for that. They just never had that secure, locked-down feel. I also don’t love the look of the shoe (from one side). If you’re looking at the lateral side – great looking shoe. If you’re looking at the medial side – not such a great looking shoe. Just my thoughts.
Thomas: The Under Armour Speedform Slingshot is so close to the shoe I want from Under Armour, lighter, more responsive, and a sleek look. It falls short in the fit of the upper. I would like to see the knit mirror the lateral (outside) of the shoe and be able to get a better fit with the lacing. The heel cup fit needs to be addressed to get this shoe to the next level. When I first tried on the shoe I thought it was going to be too firm for my tastes. I ended up doing something I don’t typically do, I wore the shoe casually for a day. I believe that day helped break the shoes footbed in. Most shoes these days don’t need to be broken in. The Speedform Slingshot doesn’t have an insole. Wearing it around softened up the shoe just enough to make my feet happy. If the shoe fits your foot better than it fits mine, you will enjoy the fast, light, snappy feel for up-tempo workouts and races. The Slingshot is so close, but the fit had it missing the mark.
Meaghan: The Speedform Slingshot isn’t what I expected. It’s a minimal shoe all-around. There isn’t much to the knit upper and the midsole/outsole construction doesn’t leave much to the imagination. For me, the Slingshot doesn’t have quite enough structure for racing. All that aside, you cannot deny the quality of the shoe. This is a shoe you’ll be able to run several hundred miles in without any durability concerns.