Physical activity or food intake prior to testing did not affect the reproducibility of GH secretion elicited by GH releasing hormone plus GH‐releasing hexapeptide in normal adult subjects

objective Growth hormone deficiency (GHD) in adults is a defined syndrome of which the adverse effects on different areas of body function are reversed under replacement therapy with GH. The diagnosis of GHD is controversial in adults, relying on the GH secretion elicited by the so‐called provocative tests of GH reserve. Most of the tests in use, including the widely employed insulin tolerance test, have been shown to be blunted after daily activities, such as mild exercise, heat or food intake, which makes stringent testing conditions mandatory in order to assure reproducibility. The combined administration of GH releasing hormone (GHRH) and GH‐releasing hexapeptide (GHRP‐6) is a very effective test for the diagnosis of GH deficiency in adults. In the present study, the perturbatory action of mild physical activity and food intake on the reproducibility of this combined test was assessed.