ABSTRACT
This chapter reexamines the norepinephrine hypothesis advanced as an explanation for the reductions in depression and anxiety reported by humans following physical activity (Morgan, 1985a; North et al., 1990; Petruzzello et al., 1991; Ransford, 1982). Previous discussions of the norepinephrine hypothesis have not provided sufficient detail about the role of norepinephrine in depression and anxiety. These reviews have also failed to provide biologically plausible explanations regarding the effects of physical activity on norepinephrine, or to provide direction for subsequent research.
