Brandon Lilly is one of the strongest men on the planet, an elite powerlifter who’s squatted 843 pounds.

But then a knee injury sidelined him in 2014. “I had to look at myself in the mirror,” he says. “The whole reason I got into powerlifting was to look better, feel better, and get stronger. The only thing that had improved was my strength.” At 345 pounds, Lilly couldn’t walkthrough a shopping mall without getting winded. “I wouldn’t have been able to run to save my own life,” he says.

As he rehabbed his knee, Lilly found Belisa Vranich, Psy.D., a clinical psychologist who is also a breathing coach to celebrities, athletes, and military personnel. It’s not news that deep breathing confers many benefits. But like Lilly, many overlook its gym advantages. Lilly learned he was a “vertical breather,” doing the equivalent of a shrug every time he inhaled. By not using his diaphragm, Lilly’s breathing was less than optimal.

Vranich taught Lilly to expand and contract his midsection, better oxygenating his muscles and organs and creating a more stable base for his lifts. The results came right away. Before his first lesson he’d be gassed after eight squats with 315 pounds. After? He did 23 straight reps. Life outside the gym improved too. Once lethargic, Lilly now feels more energetic. But all he’s running on is air.

via How to Breathe During Your Workout to Be Stronger and Effective