I got into the power of breathing about two years ago, starting with the Wim Hof method—hyperventilation followed by breath holds. That felt beneficial at first, but as I kept learning, I came across the topic of CO₂ tolerance. That led me to the Conscious Breathing website, and what I read about the CarboHaler and its potential benefits really resonated.

I received my CarboHaler around 11 months ago and have used it multiple times per week ever since.

I race cross-country mountain bikes at the national level in the UK. Since integrating the CarboHaler into my routine, I’ve seen a significant drop in lactate build-up and can push past the point where I used to tie up and lose wattage. I’m now replicating power outputs similar to what I was doing 10 years ago.

Last season, I was often on the podium but rarely on the top step—usually finishing second and about 1–2 minutes behind the winner. This year, however, after a winter training block using the CarboHaler and switching to nasal breathing, I’ve won the first four rounds of the national series in my age category—each by a solid margin of 1-2 minutes. I’ve had noticeably more energy and can ride past the levels that used to fatigue me. According to the data from my Wahoo bike workouts, I’m performing about 10% better overall compared to last year.

I now use the CarboHaler 4–5 times a week before workouts, usually for about 10–12 minutes at 7% CO₂. I started out slowly—just 4 minutes per session—and built up gradually to where I am now. It’s become a key part of my pre-ride routine.

Beyond cycling performance, I’ve noticed other benefits too. I feel more relaxed and less anxious when dealing with stressful situations. My recovery between sessions has improved, and my perceived effort during training is lower.

To complement the CarboHaler, I recently added the Relaxator to my toolkit—for calm, stress-free breathing to further support recovery and nervous system balance.

All in all, I can’t recommend the CarboHaler enough. It’s made a real difference—not just in how I race, but in how I feel day-to-day. It might even be life changing.

Marc Chamberlain, 52, United Kingdom
Cross-Country Mountain Bike Racer, National Series Winner