Polar bears have paws specially adapted to meet both terrestrial and aquatic demands. They are Large, wide, and flexible and spread outward to distribute weight over a broad surface area, thereby easing travel over snowy and icy terrain.

In the water, the wide surface area provides a paddle–like effect, which is enhanced in the forepaws by webbing between the toes. The hind feet and legs are held flat and are used as rudders. These adaptations enable polar bears to swim using a dog–paddle stroke, with front–to–back limb movements within the limits of leg and joint anatomy.

A polar bear's nostrils close when they are under water. They can remain submerged for as long as two minutes. They can swim for several hours at a time over long distances. They've been tracked swimming continuously for 100 km. The thick layer of blubber (fat), keeps the polar bear warm while swimming in cold water.