Physiology & ScienceBlood Shift in Freediving: Bradycardia and Your Body at Depth
The blood shift freediving depends on, explained: how blood moves into your chest as your lungs compress, why your heart slows, and the link to lung squeeze.
Blog topic · 6 articles
Physiology & Science
The mammalian dive reflex, blood shift, the spleen effect, CO2 vs O2 and the physics of pressure, explained in plain language.
Physiology & SciencePhysiology & ScienceBoyle's Law in Freediving: Pressure and Depth Made Simple
The Boyle's law freediving courses teach, made simple: how pressure rises with depth, what it does to the air in your lungs, ears and mask, plus a depth table.
Physiology & ScienceLung Capacity and Freediving: Does Size Really Matter?
How much lung capacity freediving really needs: what TLC, FRC and residual volume mean, why big lungs help less than you think, and what you can improve.
Physiology & ScienceMammalian Dive Reflex: How Your Body Switches to Dive Mode
The mammalian dive reflex slows your heart, narrows blood vessels and squeezes your spleen when you hold your breath underwater. What it means for freedivers.
Physiology & ScienceThe Spleen Effect in Freediving: Why Later Holds Feel Easier
The spleen effect freediving coaches talk about: how repeated breath-holds release extra red blood cells, how long it lasts and how to plan safe warm-up holds.
Physiology & ScienceThe Urge to Breathe: Why CO2, Not Oxygen, Sounds the Alarm
Your urge to breathe is driven mostly by rising CO2, not falling oxygen. How your body's gas sensors work, and why that mismatch matters for freediving safety.