This is a conversation that reveals the core principles of "efficient breathing" -- techniques that can transform athlete performance and recovery as well as everyday health. Renowned science journalist James Nestor explains that most people breathe surprisingly inefficiently and introduces simple breathing assessments and training methods anyone can follow. He clearly explains why breathing matters, what the actual training methods are, and how they can bring significant change to both athletes and everyday people.

1. The "Power of Breathing" That Athletes Are Paying Attention To

Recently, athletes seeking to optimize their condition and performance have begun paying serious attention to breathing. What is interesting is that athletes are accustomed to discomfort and difficulty, so they approach even small differences with great seriousness.

"Athletes aren't afraid of small discomfort or pain. That's actually the environment they dive into to get ahead of everyone else."

In particular, big wave surfers depend on breathing for their very survival, which makes them deeply invested in learning how to hold their breath longer and control their breathing.

"If you don't practice proper breathing, your life could be at risk."

One famous surfer who looks like he's in his 30s despite being 60 credits his consistent "breathing training" for this. On the other hand, many runners, rowers, and baseball or soccer players are still unfamiliar with this "breathing secret."

2. Even Elite Athletes Struggle with "Basic Breathing" -- Why and What Goes Wrong

The very first thing elite trainers actually have athletes do is "breathing retraining." Surprisingly, the vast majority of athletes fail to properly use their diaphragm, the primary breathing muscle.

"Most athletes -- you'd think they are people who really focus on breathing, but they're not at all. Everyone's breathing is a complete mess."

The real problem is that when inhaling, people only expand their chest and hardly use the diaphragm (the large muscle located below the chest). This drastically reduces breathing efficiency.

"If you breathe only with your chest, you're just wasting energy -- it's too inefficient."

When continuing shallow chest breathing without using the diaphragm, you cannot take in enough oxygen in a single breath, forcing you to breathe much more frequently. As a result, your heart rate rises unnecessarily. This creates a structure where fatigue sets in faster and recovery slows down during exercise.

"Even if you only breathe 10 or 20 times per minute, your heart rate is much lower than when breathing 40, 60, or 100 times. That means greater endurance and faster recovery."

When these principles are actually applied, performance visibly improves and recovery accelerates, as shown by measurable data.

3. The Most Important Fundamental: Nasal Breathing

So what constitutes proper breathing habits? It is emphasized that breathing exclusively through the nose during low- to moderate-intensity exercise is crucial.

"Among people jogging in the morning, you can count on one hand those who breathe through their nose. But this is truly the key."

Just changing this small habit can dramatically improve performance, recovery, and endurance.

4. The BOLT Test: A Simple Breathing Efficiency Assessment Anyone Can Do

The video also introduces a simple test for measuring breathing efficiency: the "BOLT score (Body Oxygen Level Test)." Long referred to as a blood oxygen level indicator, it actually evaluates "carbon dioxide (CO2) tolerance" and the resulting efficient breathing capacity.

The test procedure is as follows:

1. Relax everything -- shoulders, face, and tongue.
2. Breathe in and out naturally through your nose only (three normal breaths, not deep ones).
3. After the last exhale, pinch your nose and hold your breath.
4. Hold your breath until the first moment you feel the urge to breathe -- when your belly (diaphragm) starts to flutter or you feel the need to swallow -- and record the time in seconds.

"This is absolutely not a competition. There's no need to push yourself. If you genuinely need to breathe, just stop and note the time."

This score can fluctuate easily depending on your condition, sleep, and stress levels, but with consistent practice of proper breathing techniques, it can improve dramatically.

"If you focus on breathing and learn to breathe less, deeper, and slower, your BOLT score could double or triple within a week or two."

The higher the BOLT score, the greater your CO2 tolerance and the more efficient your breathing. In other words, being able to "endure longer while breathing less" is proof that your body's oxygen supply is being well maintained.

5. Another Key to Breathing Training: Posture and Muscles

Breathing technique is not just about how you breathe -- it also brings major changes to body posture (biomechanics) and the use of breathing muscles. Whether you are an athlete or a regular person, many of us forget deep, wide abdominal breathing as we grow up, but training can fundamentally change this.

"Feel how far down your ribs (thorax) can expand. When you know the sensation of breath filling your entire body, even your exercise posture and muscle control will change."

LeBron James, the famous basketball player, is cited as an example -- during mid-game breaks, he practices Alternate Nostril Breathing, and you can see his belly and chest both moving deeply and cleanly.

"This is biology, not psychology. Proper breathing can bring the biggest change to athletes."

Conclusion

Just changing the way you breathe can lead to dramatic improvements in sports performance, recovery, and even everyday health. Try a quick self-assessment with the BOLT test, and start by practicing deep, slow nasal breathing and fully engaging the diaphragm in daily life. Remarkable changes may follow.