Figure 14. Paradoxical reduction in blood pressure during supine exercise in a participant who had undergone sympathectomy to treat hypertension.

Line chart displaying the paradoxical reduction in arterial blood pressure associated with two minutes of supine cycling exercise which, in a separate experimental exercise, was not attenuated by a 15-degree head down tilt designed to facilitate cardiac filling. These data represent a 44-year-old man who had undergone thoracolumbar sympathectomy for essential hypertension. Blood pressure was recorded from the radial artery using a Statham strain-gage transducer. Adapted from Marshall et al (230).