Figure 2.

Association of objective sleep quantity and quality with levels of plasma hormones (Panel (A–C): DHEAS, Panel (D–F): Free testosterone, Panel (G–I): Somatotropin, and Panel (J–L): Cortisol) in sedentary middle-aged adults. β (standardized regression coefficient), R², and p-value from a simple linear regression analysis. Significant p-values (<0.05) are in bold. Open circles represent men, closed circles represent women, and the straight solid line represents women. DHEAS: dehydroepiandrosterone sulphate.