Under Armour Threadborne Slingflex

The Under Armour Threadborne Slingflex is a cushioned, neutral, road running shoe. It was designed to be strong, supportive, and lightweight with a breathable and compression-like fit. The Charged Cushioning has two layers: one for softening landings, absorbing shock, and returning energy, and the other for stabilizing and supporting the foot during takeoffs and landings. The Threadborne upper is breathable, durable, flexible, and lightweight, made with strong knit Dyneema material that delivers a sock-like feel. Inside the shoe, the heel counter has padding for comfort, stability, support, and protection. The mesh tongue has supportive padding for a comfortable fit. There is also a removable Micro G sockliner that forms to the shape of the foot and offers great cushioning. The outsole has solid rubber on high impact areas and softer rubber everywhere else, making it lightweight, flexible, comfortable, and durable. If you need a comfortable daily running shoe, read on to see if the Threadborne Slingflex is right for you.

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Where to Buy
Road Runner Sports Link
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Where to Buy
Road Runner Sports Link
See Deal
Pros & Cons
  • Colors are subtle, not flashy
  • Very comfortable
  • Lightweight
  • Supportive
  • Good flexibility and durability
  • Laces stay tied
  • Cons
    • Sizes can run slightly small
    • May rub ankle without socks
    • Might take time to break in
    • Slightly narrow toe box
    • Key Features
      The outsole uses both solid and soft rubber. The solid rubber is in the high impact areas for durability and the softer rubber is everywhere else for a softer landing and energy return. Both types of rubber are lightweight. The outsole has treads going horizontally across the forefoot with rectangular shapes, and circular treads in the heel. The midfoot has solid rubber on the outside for durability and softer rubber on the inside for comfortable support. The grooves between the treads add flexibility to allow the foot to move naturally and have smooth transitions.
      The midsole consists of Charged Cushioning and a Micro G sockliner. The Charged Cushioning has a top layer that absorbs shock to protect joints, cushions landings for comfort, and returns energy for speed and endurance. The bottom layer is more solid and is used for support and to stabilize landings to prevent injury and allow users to pick up speed. The foot-shaped Micro G sockliner on top is removable and provides a customized, cushioned fit. The arch support is neutral. The standard range offset helps keep the foot moving forward to improve speed and responsiveness.
      The upper uses Threadborne, Dyneema, and mesh. Threadborne is lightweight and breathable, while also being durable enough to last for many runs without wearing through, and flexible enough to allow the foot to move freely. Dyneema is a very strong fabric used in the knit construction, which provides durability. Dyneema is also flexible and comfortable, delivering a sock-like feel. There is an internal heel counter that is padded, which stabilizes the rearfoot to protect against rolling but also provides support and comfort. The tongue is made of padded mesh for additional support and comfort. The upper also has a toe cap to prevent stubbing and bruising, and laces that stay tied and provide a snug fit.
      The men's shoe weighs 9.8 oz and the women's shoe weighs 8.1 oz. Testers noted how lightweight the shoe felt when running in it. The shoe keeps its weight low by using a mixture of lighter and heavier components, with even the heavier components not adding very much weight to the shoe. The outsole uses two kinds of rubber instead of one, and even the solid rubber is not too heavy. The midsole's Charged Cushioning has a lighter, softer layer on top and a denser bottom layer on the bottom. The Micro G sockliner is also lightweight and is removable so it can be replaced with a different (heavier or lighter) insole. The Threadborne, Dyneema, and mesh are all lightweight and are thick enough to be durable but thin enough to be lightweight and flexible.
      The Under Armour Threadborne Slingflex is very breathable. Threadborne is very breathable and is used throughout the upper. Dyneema is used in a knit construction to allow air to flow around it. The tongue uses mesh for breathability. The fabric is woven rather than stitched, which makes for a comfortable fit because air can flow freely without having to worry about blisters or rubbing against the foot.
      The Threadborne Slingflex is very comfortable according to reviewers. It has a standard width and the length is mostly standard although a few people decided to order a half-size up because it was slightly short. Some people found that it felt great without socks, while others had trouble with rubbing around the ankles when they wore socks. Most people did not experience any rubbing or blisters, although a few testers noted that it may take some time to break in. The laces stay tied so you do not have to worry about tripping or having the fit loosen during a run. The toe box is slightly narrow compared to other shoes, which is great for narrow to medium feet, but not so great for those with wider feet. The soft rubber in the outsole helps create comfortable landings, along with the top layer of Charged Cushioning and Micro G sockliner in the midsole. The sockliner can also be replaced with a gel insole or medical orthotic if necessary. The upper has a padded tongue, heel, and collar, and the fabric is breathable to prevent overheating during long runs or hot days. Dyneema provides a comfortable, sock-like feel. The light weight, flexibility, and responsiveness also make the shoe comfortable to wear for long runs.
      This shoe comes in seven different colors for men and nine for women. The shoe has a woven pattern on the upper with lots of holes for breathability. The colors are subtle, which reviewers who do not like flashy colors were happy about. The only complaint was that not all colors are available in every size due to the popularity of certain colors.
      Designed for strength, the Under Armour Threadborne Slingflex is a very durable shoe. The outsole uses solid rubber in high impact areas, and testers noted that the outsole showed no sign of wear other than being dirty after 100 miles of use. The midsole is also durable, having a Micro G insole as well as a two-layer Charged Cushioning that continues to cushion landings and bounce the foot back into the air after many miles. The upper uses Dyneema, which is very strong and durable, Threadborne for lightweight durability, and a padded heel, tongue, and collar for supportive durability. The shoe is estimated to last a few hundred miles before signs of wearing start to appear.
      The Threadborne Slingflex offers good protection. The outsole and toe cap protect against bruising from objects under or in front of the foot. The outsole and bottom layer of Charged Cushioning stabilize landings to protect against slipping. The top layer of Charged Cushioning and the Micro G sockliner protect joints during landings by absorbing shock. The midsole and upper support the arch to protect against light over-pronation. The upper protects against heat with its breathability as well as against rolling or sliding with its support and internal heel counter.
      This shoe has good responsiveness. The outsole uses soft rubber to add a little extra spring to the wearer's step, and the treads and grooves provide a good ground feel and smooth transitions. The midsole's Charged Cushioning and Micro G sockliner help bounce the foot back into the air after absorbing shock. The upper is strong but flexible, keeping the top of the foot stable but allowing it to move naturally.
      The Under Armour Threadborne Slingflex is very supportive. The outsole's rubbers lift the foot off the ground and provide underfoot support. The midsole supports the foot with its Charged Cushioning and Micro G sockliner that conform to the shape of the foot, creating customized support. The upper uses Dyneema for socklike support and has supportive padding in the mesh tongue, the collar, and the internal heel collar. The arch support is minimal, good for neutral runners and not forcing an arch for flat feet.
      The Threadborne Slingflex is a road running shoe. Its treads indicate that it was designed to go on hard surfaces, such as paved roads, dirt roads, gym floors, paths, or light trails. It can also go on wet terrain without problems, although it does not do as well on technical trails, ice, or snowy terrain due to its lack of lugs.
      This shoe is averagely priced. It is lightweight, comfortable, and durable, and the materials used are high quality, which makes it a great deal for someone looking for a daily running shoe. There are minor issues with fit and comfort, but not enough to make almost anyone give a less than positive review. Current prices range from 30% off to 80% above the initial price of the shoe. Some sizes and colors are more popular than others. The more popular sizes/colors are either sold out or have higher prices, and the less popular sizes/colors go for lower prices.
      The Under Armour Threadborne Slingflex has great traction on both wet and dry terrain. The treads do a good job gripping dirt and paved roads and hard surfaces, allowing runners to have stable landings and takeoffs and to pick up speed because of their solid footing. The shoe can also ascend and descend hills on roads and paths without the wearer having to worry about slipping.
      The Threadborne Slingflex has good flexibility. The outsole has grooves in the softer rubber to allow the shoe to bend easily. The midsole's Charged Cushioning and Micro G sockliner are able to bend to the shape of the foot. The upper has flexible Threadborne fabric to allow the toes to splay and push off.
      This shoe is in the neutral category. It has some stability for landings and light over-pronation but is generally not designed to correct over-pronation. The solid rubber in the outsole and the bottom layer of the Charged Cushioning stabilize landings to prevent slipping. The upper has an internal heel counter to stabilize the rearfoot and Dyneema for light stability on the top of the foot. There is some padding on the tongue, collar, and arch to stabilize neutral runners against rolling.
      The drop is 10mm, which is in the standard range. This helps with comfort and protection, as it means more padding in the heel to absorb shock and less strain on the Achilles heel when running. It also means better responsiveness, since the extra cushioning in the heel helps bounce the foot back into the air, especially when used by a heel striker.
      Key Features
      • Charged Cushioning adds comfort, absorbs shock, returns energy, supports and stabilizes landings

      • Threadborne upper is lightweight, breathable, durable, and flexible

      • Dyneema knit construction is strong, durable, flexible, and delivers a sock-like feel

      • Internal heel counter has soft padding for comfort, support, stability and protection

      • Padded mesh tongue supports the foot and provides a comfortable fit

      • Micro G sockliner is removable and offers a foot-shaped cushioned fit

      • Outsole uses solid rubber on high impact zones for lightweight durability

      • 10mm offset
      Bottom Line
      The Under Armour Threadborne Slingflex is a great shoe for someone looking for a daily trainer. It is lightweight, breathable, cushioned, supportive, durable, flexible, and has good energy return. The Threadborne and Dyneema upper materials flex and move well together. There is a good selection of color options that look nice but are not too flashy, so they appeal to most people. The price is very reasonable. The Threadborne Slingflex is stable enough for neutral runners to go on roads or light paths, and has good traction on both wet and dry surfaces. It could be slightly improved in the areas of fit and ankle irritation, and the toe box could be wider, but overall it is very comfortable. In fact, some testers thought it was one of the most comfortable shoes of the year. Overall, the Threadborne Slingflex is an awesome, classic-looking shoe great for the daily runs of new and seasoned runners alike.
      Where to Buy
      Road Runner Sports Link
      See Deal
      By Stephanie Potter
      Last updated:
      Where to buy
      Best offer on: Jul. 29. 2021

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