The Gravity Doctors

In this episode, we dive into the surprising science of "gravity intolerance" and why lying in bed might be one of the worst things you can do for your recovery. Whether you're dealing with a common flu, recovering from major surgery, or managing a long-term illness, the simple act of gettingvertical can be a "physics-fighting engine" for your body and mind. We explore NASA’s "Pillow-naut" studies, the link between inactivity...

In this episode, Dr. Brennan Spiegel (physician, gastroenterologist, and author of Pull) and Dr. Lachlan Kent(cognitive scientist and founder of Mental Gravity) explore the physical, psychological, and existential implications of humanity's return to the moon.

They examine how the Artemis mission acts as a "Global Unifier," shifting the narrative from territorial conflict to a collective human achievement.

Broadcasting as a "crew of ...

Dr Lachlan Kent is joined by Dr Mats Niklasson, developmental psychologist, visiting Research Fellow at the University of Greater Manchester, and co-founder of Sensorimotor Therapy, to explore how early vestibular development shapes both physical coordination and the narrative sense of self.

Drawing on nearly 40 years of clinical work with children and adults experiencing coordination and concentration difficulties, Mats explains ho...

Dr Brennan Spiegel (physician, gastroenterologist, and author of Pull) and Dr Lachlan Kent (cognitive scientist and founder of Mental Gravity) explore how seasons, sunlight, serotonin, and gravity shape mood, attraction, and human connection.

Broadcasting from opposite hemispheres—Brennan in winter in Los Angeles and Lachlan in summer in Melbourne—they examine why people often feel more “down” in winter, why ...

Dr Lachlan Kent and Dr Brennan Spiegel are joined by Elisa R. Ferrè, professor of cognitive neuroscience at Birkbeck, University of London, and one of the world’s leading experts on graviception and the vestibular system.

Together, they explore how the brain senses gravity without a single “gravity receptor,” why the vestibular system has no primary cortex, and how gravity is computed as a distributed, multisensory...

Dr Brennan Spiegel (physician, gastroenterologist, and author of Pull) and Dr Lachlan Kent (cognitive scientist and founder of Mental Gravity) drop an emergency episode to unpack one of the most extreme acts of gravity defiance ever witnessed: Alex Honnold climbing a 100-plus-storey skyscraper without ropes.

Using Honnold as an “extreme phenotype,” they explore what his remarkable calm reveals about fear, anxiety, gravic...

How do elite athletes use body, mind, joy, and meaning to push beyond physical limits?

Dr Brennan Spiegel (physician, gastroenterologist, and author of Pull) and Dr Lachlan Kent (cognitive scientist and founder of Mental Gravity) explore theOlympics as humanity’s greatest laboratory for defying gravity.

With the Winter Olympics approaching, they examine elite athletes as “physics-fighting engines”—bodies and ...

Dr Brennan Spiegel (physician, gastroenterologist, and author of Pull) and Dr Lachlan Kent (cognitive scientist and founder of Mental Gravity) explore serotonin as a gravity-management molecule, reframing it not simply as a “happiness chemical,” but as a fundamental biological system that allows life to stand up, move fluids, regulate balance, and remain psychologically buoyant in a gravitational field.

Together, Brennan...

Dr Brennan Spiegel (physician, gastroenterologist, and author of Pull) and Dr Lachlan Kent (cognitive scientist and founder of Mental Gravity) explore how diet, microbiome diversity, and serotonin production shape your capacity to stand up to gravity—physically and mentally.

They introduce the Anti-Gravity Diet and Brennan’s STACK TEN framework, a simple, evidence-informed way to support the gut’s serotonin “...

In this episode, Dr Brennan Spiegel (physician, gastroenterologist, and author of Pull) and Dr Lachlan Kent (cognitive scientist and founder of Mental Gravity) dive deep into gravity resilience and introduce listeners to the new Gravitype Quiz—a wellness tool that blends biomechanics, neuroscience, and psychology to help people understand their personal relationship with gravity.

Together, Brennan and Lachlan take the quiz liv...

Dr. Brennan Spiegel (Cedars-Sinai) and Dr. Lachlan Kent explore how gravity shapes not only our bodies but our minds. Through the lens of Cathy Freeman’s gold-medal run, they discuss mental gravity — the feeling of emotional “weight” and lightness that defines human experience.

From Einstein’s relativity to embodied cognition and Cedars-Sinai’s virtual-reality therapy, they connect physics, psycho...

In this uplifting and deeply human episode of The Gravity Doctors, Dr. Brennan Spiegel (Cedars-Sinai gastroenterologist and author of PULL) and Dr. Lachlan Kent (cognitive scientist and theorist of Mental Gravity) sit down with Harmon Clarke, a patient-turned-researcher whose remarkable recovery story illuminates the future of biogravitational medicine.

From septic shock and 200 days in hospital to yoga teacher, breathwork practitio...

Biogravitational Medicine is a holistic approach to maintaining health in both body and mind. It's like a toolkit where you can find what works for you and your particular situation. Here are our top ten that work for most people most of the time. (As always, consult a doctor for personalised medical advice before attempting anything that might pose a risk to your physical or mental health, or for treatment of acute or chronic cond...

Dr Spiegel has written a book about gravitational health called 'Pull' on the wide ranging themes underpinning this podcast - gut health, mental gravity, serotonin, the inner ear, the body's pumps and tubes, the gravitostat, and many more. The hosts take a tour through the world of biogravitational medicine by telling the story of what inspired the book, where the science is heading, and how people can apply the principles in their...

You know the feeling you get in your belly when falling on a rollercoaster? Ever wondered why we get similar gut feelings when we're "falling" in love?  In this episode, Brennan (a gastroenterologist) and Lachlan (a cognitive scientist) talk about how gravity shapes gastrointestinal function and what relation gut feelings have to physical and mental health. They discuss Brennan's viral scientific paper, "Gravity and the Gut: A...