The Haywire Heart: How too much exercise can kill you, and what you can do to protect your heart

Most endurance athletes love the feeling of pushing harder, going longer, and testing what the body can really do. But The Haywire Heart asks the question few of us ever stop to consider: what if all that effort isn’t always good for you?

This groundbreaking book digs into what really happens when training intensity and volume go beyond what the heart can safely handle. Whether you’re a cyclist, runner, triathlete or cross‑country skier, it’s an eye‑opening look at the growing research around “athlete’s heart” — and the real risks that come with chronic overtraining.

Cardiac electrophysiologist Dr John Mandrola, along with co‑authors Lennard Zinn and Chris Case, breaks down complex conditions like arrhythmia, atrial fibrillation, tachycardia, hypertrophy and coronary artery disease in a way athletes can actually understand. You’ll learn how inflammation, recovery, duration and intensity all play a role in long‑term heart health.

The book also shares gripping real‑life stories from elite and everyday athletes — including the terrifying cardiac episode that nearly killed Zinn — and tackles tough topics like exercise addiction and the “tough it out” mindset that stops athletes from seeking help.

Most importantly, The Haywire Heart gives you practical tools: how to talk to your doctor, which tests matter, what treatments look like, and how to adjust your training so you can stay active without putting your heart at risk. It’s essential reading for anyone who trains hard, whether you’re chasing podiums or simply trying to stay healthy for the long run.