Firm vs Plush: Understanding Cushioning Levels in Running Shoes
"Cushioning" is one of the most misunderstood words in running shoe marketing. Brands use it to mean different things, reviewers use it subjectively, and most of what you read conflates at least two separate properties — midsole hardness and stack height — that affect the underfoot feel in different ways.
This guide separates what cushioning actually means, how to measure it, and how to match it to your running.
Two separate properties, one word
When runners say a shoe "feels cushioned," they are usually describing a combination of:
Stack height: How much foam sits between your foot and the ground, measured in millimetres at the heel and forefoot. A higher stack height means more material between you and the road, which generally means more impact absorption and a more removed feeling from the ground.
Midsole hardness: How stiff or soft the foam material itself is, measured in Shore C units on a durometer. Softer midsoles compress more under load; harder midsoles compress less. Counterintuitively, a harder midsole can actually protect the joints better than a softer one — because it provides controlled, consistent support rather than unpredictable collapse.
The confusion comes when these two properties go in opposite directions:
- High stack, firm midsole (Hoka Clifton): Lots of foam, but it doesn't feel spongy. Well-cushioned in terms of impact absorption. Stable.
- High stack, soft midsole (Hoka Bondi): Maximum impact absorption. Can feel unstable at faster speeds. Best for very slow running or walking.
- Low stack, responsive midsole (Saucony Kinvara): Close to the ground, snappy. Not cushioned in the traditional sense — the energy goes back into propulsion rather than absorption.
- Low stack, firm midsole (racing flat): Maximum ground feel and proprioception. Only suitable for fast efforts where injury protection is secondary.
How to think about it for your running
Heavier runners (90kg+) benefit from higher stack. More material is needed to cushion the higher forces generated by heavier bodyweight. This is why the Bondi is frequently recommended for heavy runners — it provides enough material that the midsole doesn't bottom out at impact.
Faster runners benefit from firmer midsoles. A softer midsole wastes energy at faster paces — the foam compresses and the energy is absorbed rather than returned. For speed work and races, look for midsoles with higher energy return percentages.
Daily trainers benefit from the middle ground. For most runners doing most of their running in the 5:00–6:30 /km range, a moderate-stack, responsive-but-not-rock-hard midsole provides the best combination of protection and feel. The Brooks Ghost 16 and Nike Pegasus 41 both sit in this zone.
How we measure cushioning on SoleHunt
In our shoe database, cushioning is characterised by three lab measurements:
- Midsole hardness (Shore C): Lower number = softer. We measure at the heel pad.
- Heel stack height (mm): Total material under the heel.
- Energy return (%): How much energy the midsole returns on compression. Higher is more responsive.
These three measurements together give a precise picture of a shoe's cushioning profile. A shoe with 32mm heel stack, 32 Shore C hardness, and 68% energy return sits in a very different position from one with 38mm stack, 20 Shore C, and 45% energy return — even if both are described as "plush" in reviews.
Quick guide
| You are looking for | Prioritise |
|---|---|
| Impact protection for long slow runs | High stack + moderate-soft midsole |
| Responsive feel for speed work | Moderate stack + firm midsole + high energy return |
| All-around daily trainer | Moderate stack + moderate hardness + moderate return |
| Maximum comfort / recovery | Maximum stack + soft midsole |
| Racing / personal bests | Low stack + firm midsole + very high energy return |
Use the SoleHunt finder and select your cushioning preference to see shoes matched to your specific combination of weight, use case, and feel preference.