To evaluate the influence of drugs, e.g., spinal anaesthesia, or diseases on baroreflex blood pressure control one would like to have a test which causes a step wise change in blood pressure (BP) which persists for long enough to allow dynamic properties to be studied. The Valsalva manoeuvre evokes large changes in BP, but it can be maintained only relatively briefly, while it induces multiple effects caused by the active straining. It also involves certain risks for patients with retinopathy. In this study a modified Valsalva manoeuvre is proposed, which induces a large step wise BP decrease and increase without these disadvantages. With informed consent and approved by the ethical committee of the Vrije Universiteit Ziekenhuis Amsterdam, 10 control subjects performed the new manoeuvre in the sitting position. The manoeuvre is called DIBEX manoeuvre: Deep Inspiration, Breath-holding against a closed glottis while relaxing thoracic and abdominal muscles, no straining, and after 40 s EXpiration. Beat-to-beat BP was measured noninvasively with the Finapres™, as the heart rate (HR) was recorded. The DIBEX manoeuvre was expected to provoke a large instant reduction in venous return, due to a positive intrathoracic pressure, 40 s later followed by an inverse step wise increase in venous return. Systolic BP, within 6–8 beats, dropped by 40–60 mmHg, but within 10–20 s a steady state was reached just below control level, due to baroreflex control. After breath release BP showed a large overshoot due to pooled venous blood now pumped into the constricted arterial system. Note the large reduction in pulse-pressure (at time 60 s) Fig. 6, indicating a small stroke volume, caused by a depressed venous return. HR showed a vagal and sympathetic mediated tachycardia, with a slight overshoot during breath holding; after breath release a strong vagus mediated bradycardia follows within one beat.Fig. 6. (abstract 14).: Pulse and blood pressure responses to breath hold.The DIBEX manoeuver, in contrast with the Valsalva, requires no straining, thus, no exercise reflexes. It evokes a clear, almost step wise stimulus long enough to study dynamic as well as steady-state control aspects of BP control. This manoeuvre is a promising test for cardiovascular and autonomic nerve functioning under physiological conditions, as well as under influence of diseases or drugs.