What are anti-fatigue mats?

This interesting article is very helpful in explaining the benefits of Anti-Fatigue Comfort Mats in the Home, Kitchen, Office or, come to that, any environment where standing for long periods is necessary.  Anti-fatigue mats are mats designed to reduce fatigue caused by standing for long periods.  The problem lies on a hard, surface with no ‘give’ in it.  This causes strain and fatigue on the muscles and tendons in the lower back, legs and feet.  Fatigue-reducing mats are designed to have a degree of compressibility and can be made of various materials including rubber, carpeting, vinyl, and foam.

Why use anti-fatigue mats?

According to scientific data, standing for long periods of time is particularly stressful and fatiguing. Regardless of the quality
of shoes and quality of the floor covering, standing itself can cause tiredness after an entire working day.

Check out the article itself for more detail.
Source: https://www.ccohs.ca/oshanswers/ergonomics/mats.html