Also known as White Muscle. Also known as Intermediate Muscle . Flight muscles are primary sites for shivering thermogenesis, leg muscles may also be important. Both burst shivering and continuous shivering have been reported in different birds. Cold-acclimation results in decreasing amplitude for the same level of cold stress.
Aerobic muscle appears to be recruited for shivering before anaerobic muscle in chickens.
Whether or not this is typical for birds in general is not known. The mechanism and location of NST, if present, are unknown. It is known that birds lack brown fat.