Shoe Review: ASICS GEL-Nimbus 21

Women's ASICS GEL-Nimbus 21

Plush and Stable

ASICS designed the updated GEL-Nimbus 21 for long distance runs, and it doesn’t disappoint.

The 21 is the latest version in the long line of GEL-Nimbus running shoes. Last year’s model, the ASICS GEL-Nimbus 20, worked an improved fit into the shoe, which carried over into the 2019 model. But designers made little updates to improve on the 20th anniversary shoe to maintain its standing as a comfortable, high-quality pair of ASICS running shoes.

The addition of a new midsole foam—called FlyteFoam Propel—absorbs shock and increases durability and rebound, and a new full-contact outsole makes for a smoother, more stable ride.

Here’s everything you need to know about the new ASICS GEL-Nimbus 21:

  • Heel-to-Toe drop: 10 mm
  • Weight: 9 oz, women’s; 10.9 oz, men’s
  • Category: Road, neutral
  • MSRP: $150

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A runner holds the women's ASICS GEL-Nimbus 21 running shoe

ASICS GEL-Nimbus 21 Fit

The 21 looks similar to the 20 right out of the box, but a close look at the mesh upper shows some differences.

ASICS says it used an all new engineered mesh upper to make the shoe more breathable and more supportive. Inside, a molded EVA sockliner conforms to your feet for a comfortable fit.

One Fleet Feet wear tester said the first thing she noticed was a plush, padded heel collar and tongue that made the shoe immediately comfortable. ASICS’ external heel counter provided a secure fit, and the width was comfortable even for wider feet.

The toe box is wide enough to accommodate an array of foot shapes, but one tester said she would have liked a bit more height to be able to lift her toes.

The Nimbus feels confident and stable right out of the box.

A new, full-ground-contact midsole gives the shoe support from heel to toe, and the burly build hugs your foot all the way around.

One tester says he liked how the engineered mesh lent structure to the shoe, which helped keep his foot in the middle of the footbed without feeling restricting.

Overall, the GEL-Nimbus 21 is a comfortable running shoe that combines new updates with existing technology to deliver a better all-around fit.

A runner wears the ASICS GEL-Nimbus 21 running shoe

ASICS GEL-Nimbus 21 Ride

ASICS didn’t change much about how the latest Nimbus rides, which is good news for fans of the distance shoe.

The Nimbus uses both Flytefoam Lyte and Flytefoam Propel foams to cushion the shoe. Propel gives the shoe an energetic bounce while Lyte cuts weight without cutting protection.

A Fleet Feet tester says the shoe felt like it had a thick cushion—25 mm heel height and 12 mm forefoot height—but it didn’t compress too much or feel mushy while running. And that cushion didn’t weigh the shoe down. “It feels lighter than I would have guessed from the amount of cushion,” she said.

The shoe felt bouncy and responsive on longer training runs, and it provided ample support and stability despite its classification as a neutral shoe.

But the shoe was designed for long distance, and that’s what it’s best suited for.

“It’s a solid shoe for long runs and training runs on the road,” one tester said. “As long as the fit is right, the cushion is comfortable for high mileage.”

ASICS GEL-Nimbus 20 vs. ASICS GEL-Nimbus 21

A side-by-side comparison of the ASICS GEL-Nimbus 20 and ASICS GEL-Nimbus 21

The most noticeable difference between the ASICS GEL-Nimbus 20 and the ASICS GEL-Nimbus 21 is the new edition's full ground contact outsole.

Following industry trends, ASICS filled in the outsole on the Nimbus 21. The new lateral full-contact outsole provides a smoother and more stable ride through your foot's heel-to-toe transition.

One tester says the full-contact sole made the transition from midfoot to toe noticeably smooth.

But the qualities that made previous versions good for big mileage made their way into the new shoe: an external heel counter supports your foot and ASICS' GEL reduces shock in the heel and forefoot.

ASICS redesigned the engineered mesh upper and changed up the overlays that provide a bit of structure, but the lace layout didn't change from the 20 to the 21.

The women's ASICS GEL-Nimbus 21 in an exclusive color for Fleet Feet

GEL-Nimbus 21 Technology

Like many ASICS running shoes, the GEL-Nimbus 21 is packed full of the company’s sharpest technology. Here’s what’s inside:

  • Flytefoam Propel. An energetic foam compound that provides cushion and bounce
  • Flytefoam Lyte. The lightest midsole formulation that ASICS makes still delivers continuous cushion
  • AHAR outsole. ASICS’ High Abrasion Rubber is placed on the outsole in high-wear areas to boost durability
  • GEL technology. Gel pads in the heel and forefoot reduce the shock from your foot’s impact with the ground and allow movement in multiple planes as you transition from heel to toe
  • 10 mm drop. The 10 mm height difference between the heel and forefoot shifts body mass forward to reduce the strain on your legs


The ASICS GEL-Nimbus 21 is a high-quality running shoe built for long distances and training runs. Even with plush cushioning and luxurious details, the shoe runs lighter than it looks for mile after mile of comfortable training.

Still not convinced? Don’t sweat it. Fleet Feet's return policy means you can test drive your shoes and gear without risk. If you’re not happy with the way your gear performs, looks or fits, we’ll take it back within 60 days. Plus, you’ll get free return shipping on all orders. That's our Happy Fit Guarantee.

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