Parallax by Ankur Kalra

In this fascinating episode of Parallax, Dr Ankur Kalra is joined by Dr Benjamin Levine, Director of the Institute for Exercise and Environmental Medicine and a pioneering figure in the field of space cardiology. Together, they explore the remarkable cardiovascular adaptations that occur in microgravity, and what they are teaching clinicians about treating patients on Earth. Dr Levine unpacks the haemodynamic realities of spaceflight, from the counterintuitive finding that central venous pressure actually drops to zero in microgravity, to the physiologic cardiac atrophy that results when the heart no longer pumps against gravitational load. He shares how this research has transformed the understanding and treatment of POTS, reframing it not as a disorder of the autonomic nervous system, but as a consequence of reduced stroke volume - and how horizontal exercise training borrowed directly from astronaut countermeasure programmes is now changing clinical practice. The conversation also turns to the emerging c