The flooring may not be your problem. It could be your stance. If you are preparing food in an area that has a lower cabinet with a door, open the lower door and put either your left or right foot on the threshold of the cabinet. Actually if you will be working for a long period of time, you should alternate your left and right foot. Raising your foot changes your center of gravity and takes some pressure off your back.
If you don't have a cabinet you can use in this manner, use a small footstool or a "riser" about 6 inches high.
You might want to try this before you spend any money on any mats or such.
"As a girl I had zero interest in the stove." - Julia Child
This is real inspiration. Look what Julia became!