Clay Holmes, @clayholmes21, two-time Major League Baseball All-Star and starting pitcher for the New York Mets, heads to his next destination with his Cardihaler in hand!

At the highest levels of competition, mastering your breathing is as critical as mastering your technique— and optimal breathing can be the difference between good and elite performance.

The Cardihaler is a revolutionary breathing device designed to safely increase carbon dioxide (CO₂) tolerance, enhancing oxygen delivery, focus, endurance, and recovery — all vital components for elite athletic performance.

"The Cardihaler has been an invaluable part of Clay's routine — from pitching high-pressure innings during last year's World Series with the Yankees, as well as his transition into a multiple-inning starting pitcher for the New York Mets this year!

He uses it daily before training sessions and before he pitches to sharpen focus, boost endurance, and improve recovery."
- Andy Clower, Neural Performance Consultant and Owner of @the_fitness_evolved

Research shows that improving CO₂ tolerance trains the body to use oxygen more efficiently [ref1], delays the onset of fatigue [ref2], and enhances mental resilience [ref3, ref4, ref5] — key factors that separate good athletes from great ones.

By systematically building better breathing habits and higher CO₂ tolerance, the Cardihaler helps athletes like Clay Holmes stay stronger, calmer, and more effective — exactly when it matters most.