Ask any elite endurance coach which single number matters most, and you'll hear the same answer: VO₂ max — the maximum amount of oxygen your body can use during intense exercise. It's the ceiling on your aerobic engine. Raise the ceiling, and you run faster, ride harder, and last longer. The question is: how?
Your breath is the bottleneck
Most athletes obsess over their legs, their lungs' capacity, or their heart. But the real bottleneck often sits in between: the mechanics of how you breathe under effort. When breathing becomes inefficient, your respiratory muscles work harder, stealing oxygen-rich blood that your legs desperately need. Your heart rate climbs just to keep up, and fatigue sets in earlier than it should.
Train the breathing itself, and everything downstream improves. Better oxygen delivery. A steadier heart rate. An engine that doesn't redline at mile 20.
What science says
Respiratory muscle training isn't guesswork — it's backed by published research. The GO² device is the only breathing device scientifically proven to increase oxygen and endurance while lowering heart rate, and the results are measurable:
- Endurance up 6% — a real, meaningful gain for runners, cyclists, and triathletes
- VO₂ max up 4% — raising the ceiling on your aerobic performance
- Lower heart rate — more work done at less cardiovascular cost
A few percentage points might sound small until you translate them: at the margins of a marathon or an IRONMAN, that's the difference between hitting the wall and sailing through it.
Why it works
GO² uses patented technology to position the jaw and tongue in a way that opens the airway and engages the diaphragm more effectively. The result is deeper, more efficient breathing exactly when you need it most — under load, at pace, when your body is screaming for oxygen. It was designed by doctors, it's made in the USA, and it's WADA legal for competition.
At just $60, it's a fraction of what athletes spend chasing marginal gains — no $300 super shoes that wear out after 150 miles, no lab fees, no subscriptions. Just better breathing, every session.
Who sees the biggest difference?
Runners chasing a marathon PR. Cyclists grinding up long climbs. Triathletes who need to run off the bike with legs that still answer. Swimmers, rowers, skiers — anyone whose sport punishes inefficient breathing. And the benefits don't stop at race day: lower perceived effort in training means you can stack more quality work, recover faster, and show up to the start line sharper than the field.
Train your breathing like you train your legs
You wouldn't skip leg day and expect a PR. Your respiratory muscles deserve the same respect. Add the GO² device to your training — warm-ups, tempo runs, long rides — and start raising your ceiling today.