What's inside your mattress: layers explained
A mattress looks like a single piece, but it's several layers stacked, each with a function. If you understand what each one does, you'll choose better. Let me explain.
The base: support
This is the layer that holds the weight and keeps the spine aligned. It can be made of pocket springs — independent springs, each in its own fabric pocket, that move individually — or high resilience (HR) foam, which is denser and firmer. In a double mattress, pocket springs help ensure you don't feel your partner move.
The middle: comfort and adaptation
Above the support are the comfort layers. Viscoelastic foam molds to the body and relieves pressure points — good for the shoulders and hips if you sleep on your side. High resilience foam responds faster and gives a floating sensation instead of sinking in.
Not all mattresses have viscoelastic foam. The Takumi does; the Mizu doesn't. It's not better or worse — it's the sensation that changes.
The top: what you touch
The top layer is the quilted fabric, sewn with topstitching. This is where the touch happens, and where the fabric helps regulate temperature. If you get hot at night, this detail matters more than it seems.
How this translates to your choice
If you have lower back pain and sleep on your back, I usually suggest more firmness and a good viscoelastic layer — the Hisui fits here. If you sleep on your side, you need adaptation in your shoulders and hips. If you share a bed, pocket springs make a real difference.
"The body decides. You can read everything about layers, but it's your 100 nights of testing that confirm it."
— Ana Cristina, Sleep Advisor
If you have chronic pain, talk to your doctor as well — the mattress helps, but it doesn't replace a clinical evaluation. Do you want to cross-reference this with your case? Take the mattress quiz or read the complete guide.
