Breathwork for Athletes: Breathing Techniques for Endurance, Stamina, and CO2 Tolerance

Breathwork for athletes is one of the most effective yet underutilized performance tools in modern sports. By incorporating these techniques into your routine, you can significantly enhance athletic performance, raise your CO2 tolerance, improve oxygen efficiency, and build the stamina and endurance needed to shorten the gap between high-intensity effort and recovery. None of this requires specialized equipment, and most of it can be trained in just 10 minutes a day.

This guide covers the breathing exercises that actually move the needle for athletes, the mechanisms behind why they work, how to apply them to running, combat, and team sports, and a simple weekly structure to get started. We also point you to the deeper video library inside our online course, where each protocol is demonstrated in full.

How Breathwork Improves Athletic Performance

Strip away the marketing and there are four mechanisms doing the work. Every breathing technique for athletes pulls on at least one of them to improve overall athletic performance.

1. CO2 Tolerance and the Anaerobic Threshold

Most athletes are not oxygen-limited. They are carbon-dioxide-intolerant. When CO2 builds up faster than the body tolerates, you breathe harder than the workload actually requires and feel gassed long before your true capacity. Raising CO2 tolerance through nasal breathing and breath hold training shifts that threshold, so you hold a higher output at the same perceived exertion. Combat coaches see it in the third round, when their fighter still looks like round one. Endurance coaches see it as a higher anaerobic threshold and better running economy.

2. Oxygen Efficiency and VO2

Oxygen efficiency is how well your body delivers and uses the oxygen you take in, not just how much air you move. Counterintuitively, breathing less (lighter, slower, nasal) often improves it. Higher CO2 tolerance shifts the oxyhemoglobin dissociation curve so more oxygen is released to working muscle, and nasal breathing adds nitric oxide that supports oxygen delivery and uptake. The practical result is better economy at a given pace and more usable output from the same VO2 max. You do not have to raise your ceiling to perform closer to it.

3. Heart Rate Variability and Recovery

Heart rate variability (HRV) is the best biometric we have for recovery, and Breathwork is one of the few interventions that consistently moves it. By engaging the parasympathetic nervous system, these techniques help reduce cortisol levels, allowing the body to transition into a state of repair. Five minutes of slow diaphragmatic breathing at roughly six breaths per minute raises HRV in real time and improves the trailing seven-day average when practiced daily. For an athlete, that is the difference between recovering overnight and showing up to the next session still in the red.

4. Arousal Regulation and Focus

Between rounds, between sets, or between plays, athletes need to drop sympathetic tone fast. The double-inhale physiological sigh manages the stress response in under 90 seconds. Box breathing does it slightly slower but with sharper focus, which is why it is standard in tactical and shooting sports. This is the closest thing to a performance cheat code you can hand an athlete, and it is the easiest technique to learn to maintain mental clarity under pressure.

The Best Breathing Exercises for Athletes

These are the core breathing techniques worth training. Each one maps to a mechanism above. You do not need all of them every day, you rotate them based on the goal of the session.

Nasal breathing under load

Default to nose-only breathing in daily life and on easy and moderate training. It raises CO2 tolerance, adds nitric oxide for oxygen uptake, and filters and humidifies air to support overall athletic performance. Start on easy efforts where you can keep the mouth closed comfortably, then extend the intensity at which you can stay nasal over a 6 to 12 week block.

CO2 tolerance training and the BOLT score

Measure your starting point with a BOLT score: after a normal exhale, pinch the nose and time the comfortable hold until the first definite urge to breathe. Most athletes start in single digits. Build it with light breath holds after a normal exhale and reduced-breathing drills. This is the highest-leverage work for endurance, and CO2 tolerance training is exactly what most athletes are missing.

Breath hold training

Beyond CO2 measurement, structured breath hold training, which can include various forms of inspiratory muscle training, builds tolerance and mental composure under air hunger. Keep it conservative. Never do breath holds in or near water without trained supervision, and progress slowly rather than chasing a maximal number.

Box breathing

Box breathing (inhale, hold, exhale, hold, each for an equal count) is the simplest arousal-control tool. Use it for mental preparation before competition to settle nerves without going flat, and between efforts to recover focus. It is a staple in tactical and precision sports for exactly this reason.

The physiological sigh

A double inhale through the nose followed by a long exhale through the mouth is the fastest known way to lower arousal. One to three rounds drops heart rate and sympathetic tone in under 90 seconds, ideal between sets, rounds, or plays.

Slow diaphragmatic breathing

Slow breathing at about six breaths per minute, driven from the diaphragm rather than the chest, is the recovery and HRV tool. Often referred to as belly breathing, this practice is essential during your cooldown or in the evening to shift into parasympathetic recovery and prime better sleep.

Breathing Techniques for Running and Endurance

Running is where breath training pays off most visibly, and breathing techniques for running is one of the most searched questions in endurance. Three things matter most. First, run easy and zone-two efforts nasal-only to build CO2 tolerance and oxygen efficiency without adding training stress. Second, use rhythmic breathing that ties breath to foot strike (a 3:2 inhale-to-exhale pattern is a common starting point) so your breathing is even and your effort is metered. Third, finish with slow diaphragmatic breathing to drop into recovery. By using these breathing drills over a training block, your nasal-only ceiling rises, which is a direct readout of improved running economy, stamina, and overall endurance.

Breathwork by Sport

Endurance sports

Running, cycling, triathlon, and rowing benefit most from nasal-only intervals and CO2 tolerance work to push the anaerobic threshold and improve metabolic economy. By training with nasal breathing, athletes can better manage blood lactate accumulation during high-intensity efforts. World-class endurance athletes routinely run lactate-threshold sessions using only nasal inhalation and exhalation. The progression is simple to program: assess your BOLT score, prescribe nasal-only intervals, and extend the intensity over 6 to 12 weeks.

Combat sports

Combat sport is the highest-leverage and easiest-to-feel application of Breathwork. Fighters who successfully drop their sympathetic tone in the 60 seconds between rounds come out for the next round with a lower heart rate and a clearer head. Beyond physical recovery, effective arousal regulation helps combat athletes control performance anxiety and reduce excessive muscle tension, allowing them to remain fluid and reactive. Wrestlers, BJJ competitors, and boxers all benefit from these targeted CO2 tolerance and recovery protocols.

Team and field sports

Football, basketball, soccer, and lacrosse use short-form protocols, such as the physiological sigh or box breathing, between plays to reset, as well as longer parasympathetic sessions for sleep and recovery across a long season. The primary goal is athlete durability, which involves keeping players physically available and recovered week after week.

Tactical athletes

Military, fire, and law enforcement professionals use the same toolset for stress inoculation under threat. Box breathing is the core tool for tactical athletes, as maintaining a steady rhythm under pressure has been embedded in doctrine for over a decade. These methods provide a reliable way to regulate the nervous system, and the benefits of this training transfer directly to the demands of competitive sport.

A Simple Weekly Breathwork Protocol for Athletes

You do not need a complicated system. A practical baseline for your training includes:

• Daily: make nasal breathing your default mode, both while you are awake and asleep.
• 5 to 10 minutes most days: focus on CO2 tolerance work, such as light breath holds and reduced breathing, or perform specific breathing drills and slow diaphragmatic breathing.
• 2 to 3 sessions per week: weave nasal-only intervals into your easy or zone-two training.
• As needed: use the physiological sigh or box breathing between efforts and on game day to regulate your nervous system.
• Evening: complete a short parasympathetic session before sleep to optimize your recovery and improve sleep quality.

Consistency beats volume. Small daily doses outperform the occasional long session.

Go Deeper: The Performance Breathing Videos in Our Online Course

Reading the protocols is one thing, watching them demonstrated and practicing along is another. Our online Breathwork course includes a library of videos focused specifically on performance breathing: nasal breathing progressions, CO2 tolerance and BOLT-style assessment, breath hold training, box breathing, the physiological sigh, and the slow diaphragmatic work that drives HRV and recovery. Unlike the Valsalva maneuver, which involves straining and can spike blood pressure, these protocols focus on controlled, sustainable airflow. Each technique is demonstrated in full so you can follow along and build the skill, not just read about it. It is the most efficient way to put everything in this guide into practice from anywhere.

For the athletic-breathing science in even more depth, Patrick McKeown's Oxygen Advantage books are an excellent further resource on nasal breathing, BOLT, and CO2 tolerance. We draw on those principles and teach how to apply them inside a broader Breathwork practice.

Frequently Asked Questions

What is Breathwork for athletes?

Breathwork for athletes is the use of structured breathing techniques to raise CO2 tolerance, improve oxygen efficiency, increase stamina and endurance, and speed recovery. It covers nasal breathing under load, breath hold training, box breathing, the physiological sigh, and diaphragmatic breathing, all applied to specific sports and goals. The aim is measurable performance: a higher output at the same perceived effort, reduced muscle tension, faster recovery between efforts, and better sleep.

What are the best breathing exercises for athletes?

The highest-leverage breathing exercises for athletes include nasal breathing under load to delay the anaerobic threshold and CO2 tolerance training using controlled breath holds. For focus and arousal control, box breathing is highly effective, while the physiological sigh helps with fast recovery between intense efforts. Other useful techniques for recovery include 4-7-8 breathing and 7-11 breathing, which help downregulate the nervous system. Slow diaphragmatic breathing at about six breaths per minute is excellent for heart rate variability. Each technique targets a different mechanism, so most athletes use several across a training week.

How do you build CO2 tolerance for endurance?

You build CO2 tolerance with controlled breath holds and reduced-breathing drills. A common entry point is the BOLT score: exhale normally, pinch the nose, and time the comfortable hold until the first definite urge to breathe. Most athletes start in single digits. Daily nasal breathing, light breath holds after a normal exhale, and nasal-only easy intervals progressively raise that number. Higher CO2 tolerance means you breathe less for the same workload, which delays the gassed feeling and pushes the anaerobic threshold higher.

What are the best breathing techniques for running?

For running, the most useful techniques are nasal-only breathing on easy and zone-two runs to build CO2 tolerance and running economy, rhythmic breathing that ties breath cadence to foot strike (such as a 3:2 inhale-to-exhale pattern), and slow diaphragmatic breathing for cooldown. Many runners start nasal-only at easy paces and gradually extend the intensity at which they can keep the mouth closed, which improves oxygen efficiency over a 6 to 12 week block.

Does nasal breathing improve athletic performance?

Yes. Nasal breathing improves athletic performance by warming and filtering air, increasing nasal nitric oxide (which supports oxygen uptake), and raising CO2 tolerance so the body uses oxygen more efficiently. Training nasal-only at easy and moderate intensities improves running economy and delays the point at which you feel out of breath. At maximal efforts the mouth still opens, but a higher nasal ceiling means more of the effort happens before that point.

How does Breathwork improve stamina and endurance?

Breathwork improves stamina and endurance mainly by raising CO2 tolerance and oxygen efficiency, so you sustain a higher output at the same perceived exertion and delay the anaerobic threshold. It also helps manage muscle tension and improves heart rate variability and recovery between sessions, which lets you train more consistently. Better sleep from evening nasal breathing compounds the effect, since endurance adaptations are consolidated during deep sleep, not during the workout itself.

Is breath hold training safe for athletes?

Light, controlled breath holds after a normal exhale are generally safe for healthy athletes and are the basis of CO2 tolerance training. Aggressive protocols, such as maximal breath holds, repeated hyperventilation, intermittent hypoxia, or breath holds in or near water, carry real risk and should never be done in water without supervision. Athletes with cardiovascular conditions, uncontrolled hypertension, epilepsy, or who are pregnant should consult a doctor first. Start conservative and never push a hold to distress.

How often should athletes practice breathwork?

A practical baseline is daily nasal breathing as the default mode, 5 to 10 minutes of dedicated CO2 tolerance or slow breathing most days, nasal-only intervals in two or three easy sessions per week, short arousal-control protocols as needed between efforts or on game day, and an evening parasympathetic session before sleep. Consistency matters more than volume.