Does Zone 1 Build a Stronger Heart Than HIIT? New MRI Data with Dr Guido Claessen & Prof Paul Laursen

Does high intensity training really build the strongest heart, or is it time in Zone 1 and Zone 2 that truly drives cardiac adaptation?In this episode, Dr Guido Claessen joins us to unpack a landmark longitudinal MRI study on endurance athletes that challenges common assumptions about HIIT and heart remodeling. They explore what actually builds the “athletic heart,” why low intensity volume matters more than most think, and what this means for polarized training.They also tackle the harder questions lifelong athletes worry about including atrial fibrillation, coronary plaque, myocarditis, and how much endurance sport might be too much.________________________Today’s speakers:Prof Paul Laursen  https://www.paullaursen.com/   Dr Guido Claessen https://www.linkedin.com/in/guido-claessen-936a18a9/