Endocrinology & Metabolic Syndrome
Open Access

Abstract

The Effect of Exercise on 1 mcg ACTH Stimulation of the Hypothalamic- Pituitary-Adrenal Axis

Alfred F Shwayhat, Thanh D Hoang, John A Poremba, Ruben D Acosta and Mohamed KM Shakir

The Low Dose (1 ?g) ACTH Stimulation Test (LDST) is useful in the evaluation of the Hypothalamic-Pituitary- Adrenal (HPA) axis. The effect of physiological stressors on its accuracy is not known. We examined the effect of prior exercise on the assessment of the HPA axis with the low dose ACTH stimulation test. Twenty-six healthy male subjects had baseline cortisol levels drawn at two-hour intervals on the initial day of the study. On day two, the LDST was performed at rest. On day three, subjects exercised by completing stage I-V of a Bruce treadmill protocol, followed by the LDST after one hour of rest. We found that mean peak cortisol levels at 30 and 60 minutes after the LDST did not differ between the day of exercise and the day of rest. The mean maximal change in cortisol levels at 30 and 60 minutes also did not differ. However, mean baseline cortisol levels before exercise began were higher on the day of exercise than on the rest day (p