Their body temperature drops to less than 46 degrees Fahrenheit [8 ° C], their heart rate drops to between three and five beats per minute, and they breathe only two or three times per minute ​ — for marmots, this is the very limit of survival.
Loomad heidavad kerra tõmbununa tihedasti üksteise kõrvale ning alustavad pikka uinakut. Nende kehatemperatuur langeb kaheksast kraadist allapoole, südamerütm väheneb kolmele kuni viiele löögile ning hingamine aeglustub kahele - kolmele korrale minutis.