Tonic sympathetic support of metabolic rate is attenuated with age, sedentary lifestyle, and female sex in healthy adults.
Bell C, Seals DR, Monroe MB, Day DS, Shapiro LF, Johnson DG, Jones PP. Tonic sympathetic support of metabolic rate is attenuated with age, sedentary lifestyle, and female sex in healthy adults. J Clin Endocrinol Metab. 2001 Sep; 86(9):4440-4.