bears hibernation period?

Researchers say bears have a very evolved hibernation capability. Bears do not eat, drink, exercise or excrete any body wastes during their five- to six-month slumber. Instead, they are uniquely able to convert toxic body wastes, and break down muscle and organ tissue to supply protein. Their fat breaks down to supply water and calories. Amazingly, a bear’s muscle mass and tissues do not atrophy in this process.