. What for some of us is a comfortable temperature is too chilly for others. People’s heat perception varies, and their sex plays a role. As the numerous thermostat battles in offices and homes can attest, women experience cold more quickly than men do. According to Dr. Ralf Brandes, who serves as a board member of the German Physiological Society and is a professor of physiology at the Goethe University of Frankfurt, "they typically have less muscle mass and therefore a lower metabolic rate, and they generate less heat." Having more muscle mass increases your rate of metabolism even at rest, meaning you burn food faster to fuel your body, a process that heats your body up. Additionally, a primary source of heat production is the voluntary or involuntary contraction of skeletal muscles through shivering. The reason men typically have more muscle mass probably lies in evolutionary history. While prehistoric men hunted – moving around and generating heat – women and children often stayed behind in their dwellings, says Dr Rüdiger Köhling, director of the Oscar Langendorff Institut für Physiologie at the Rostock University Medical Centre in Germany