Static foam mattresses redistribute pressure, but they don't change. Alternating pressure mattresses inflate and deflate in cycles, constantly shifting the pressure points. The pressure relief device market research study shows that alternating pressure overlays are the fastest‑growing type, because they're more effective at preventing ulcers, especially for high‑risk patients.

How do they work? A pump inflates and deflates cells in a pattern, mimicking the effect of a nurse turning the patient every 2 hours. The pressure relief device market trends highlight that the fastest‑growing application is medical, but industrial (factory workers who stand all day) is emerging — companies are buying anti‑fatigue mats and standing cushions.

But alternating pressure devices are noisy and require electricity. That's a problem in home care or in regions with unreliable power.

The takeaway: for high‑risk patients (elderly, malnourished, incontinent), alternating pressure is worth the investment. For low‑risk patients, a good static foam mattress may be enough.