Breathing for Cycling Performance: Mind, Body, and Sport

THE THREE PILLARS OF OXYGEN ADVANTAGE®

Oxygen Advantage® is built on three interconnected pillars:

• Body: Functional and biomechanical breathing for health, efficiency, and energy.
• Sport: Integrating advanced breathing strategies into training and racing for peak performance and recovery
• Mind: Breathwork to enhance focus, resilience, and flow state.

BODY: FUNCTIONAL BREATHING – THE FOUNDATION

The BOLT Score and Dysfunctional Breathing

The Body Oxygen Level Test (BOLT) is a simple breath-hold test after a normal exhalation. A BOLT score of 25 seconds or more indicates functional breathing, while a score below 25 seconds signals dysfunctional breathing (Kiesel et al., 2017). Low BOLT scores are linked to:

• Disproportionate breathlessness during exercise
• Poor core stability and increased risk of lower back pain
• Dysfunctional movement patterns, which can impair cycling performance, especially given the aerodynamic and restrictive posture on the bike

“A breath-hold time (BOLT score) of less than 25 seconds, along with answers to four simple questions, can be used to accurately screen for dysfunctional breathing patterns.” (Kiesel et al., 2017)

Dysfunctional breathing, including chronic hyperventilation and excessive use of accessory muscles, can lead to respiratory alkalosis and negatively impact musculoskeletal health, movement, and performance (Oxygen Advantage). Studies confirm that dysfunctional breathing is linked to dysfunctional movement patterns and that correcting breathing can improve both movement and stability (Holm et al., 2004; Kiesel et al., 2017).

Biochemical Dimension: CO₂ Tolerance, Breathlessness, and Performance

Functional breathing is fundamentally biochemical. The urge to breathe is primarily triggered by rising carbon dioxide (CO₂) levels, not falling oxygen. A low BOLT score reflects high sensitivity to CO₂, resulting in rapid, shallow breathing and earlier onset of breathlessness during exercise.

• Breath-hold time and breathlessness: As exercise intensity increases, breath-hold time decreases, and the sensation of breathlessness rises (Craig & Cain, 1957).
• Training CO₂ tolerance: Breath-hold exercises and nasal breathing increase CO₂ tolerance, reducing ventilatory drive and allowing cyclists to breathe slower and deeper, even at high intensities (Holm et al., 2004).
• Relationship with VO₂max: Endurance training blunts the ventilatory response to CO₂ (hypercapnia), and studies show a negative correlation between CO₂ chemosensitivity and VO₂max—meaning that athletes with higher VO₂max tend to have lower CO₂ sensitivity and more efficient breathing (Holm et al., 2004).

Biomechanical Dimension: Diaphragm Strength and Breathing Patterns

Efficient breathing relies on strong, well-coordinated use of the diaphragm. Nasal breathing encourages diaphragmatic recruitment, fuller breaths, and reduced reliance on accessory muscles. For cyclists, this is vital given the forward-flexed position and the need for core stability.

• Breathing pattern retraining: Retraining breathing patterns in competitive cyclists improves time trial performance and delays the onset of respiratory muscle fatigue by reducing the recruitment of accessory muscles and dynamic hyperinflation (Holm et al., 2004).
• Inspiratory muscle training: Devices like Sports Masks or inspiratory muscle trainers can add resistance, further strengthening the diaphragm and respiratory muscles, leading to improved endurance and performance.
• Diaphragm fatigue: When the diaphragm fatigues, blood is diverted from the legs to the respiratory muscles, causing premature leg fatigue and reduced cycling performance (Boyle et al., 2020; Sheel et al., 2018; Vogiatzis et al., 2008).

THE IMPORTANCE AND BENEFITS OF NASAL BREATHING DURING EXERCISE

Most cyclists do not consciously consider whether they are breathing through their nose or mouth. Many will breathe through an open mouth even at low intensity, missing out on the physiological benefits of nasal breathing. But optimal breathing for cycling performance is not just about how much air enters the body – it’s about how that air is used deep in the lungs and delivered to working muscles.

WHY NASAL BREATHING MATTERS!

• Reduces Energy Cost and Improves Efficiency:
  Scientific studies show that nasal breathing can reduce breathing rate by up to 22% during exercise, with no decrease in oxygen consumption. In a 2018 study, Dallam and colleagues found that athletes who practiced nasal breathing for at least six months maintained their oxygen intake (VO₂max) while needing less ventilation per minute, making their breathing more efficient and less tiring (Dallam et al., 2018).
  • For example, during nose breathing, the breathing rate was 39.2 breaths per minute, compared to 49.4 breaths per minute with mouth breathing, while oxygen uptake remained the same.
  • End-tidal CO₂ was higher and exhaled oxygen was lower with nasal breathing, indicating better oxygen uptake and CO₂ tolerance.
  • The study concluded that nasal breathing is 22% more efficient, and that athletes can maintain peak performance after a period of nasal breathing adaptation.
• Breathing Efficiency and Endurance:
  Nasal breathing leads to slower, deeper breaths, which maximize alveolar ventilation and minimize wasted air. This ensures fresher oxygen reaches the alveoli for transfer into the blood, supporting endurance and reducing the work of breathing (Dominelli & Sheel, 2024; Petersson & Glenny, 2014; Stickland et al., 2013).
• CO₂ Conditioning:
  Nasal breathing slows the respiratory rate, allowing CO₂ to accumulate slightly in the blood. This trains the body to tolerate higher CO₂, which is associated with reduced breathlessness and improved oxygen delivery to working muscles via the Bohr effect (Craig & Cain, 1957; Dallam et al., 2018).
• Dehydration Prevention:
  Mouth breathing increases water loss by 42% compared to nasal breathing, leading to greater dehydration and the need to drink more during rides (Edwards & Chung, 2023; Svensson et al., 2006).
• Reduced Cyclist’s Cough and Airway Protection:
  Nasal breathing filters, humidifies, and warms air, protecting the lower airways and reducing respiratory symptoms (Dallam et al., 2018).
• Improved Blood Flow and Cardiovascular Health:
  Nasal breathing stimulates the production of nitric oxide, a molecule that dilates blood vessels, improves blood flow, and may reduce blood pressure (Lundberg & Weitzberg, 1999).
• Cardiac Protection in Endurance Athletes:
  Nasal breathing during exercise may help inhibit the development of cardiac fibrosis and arrhythmia associated with chronic endurance training, by maintaining optimal CO₂ and coronary blood flow (Raphael et al., 2024).

BEYOND AIR ENTRY: ALVEOLAR VENTILATION, GAS EXCHANGE, AND CIRCULATION

• Alveolar Ventilation:
  Not all inhaled air reaches the alveoli, where gas exchange occurs. Some is lost in “dead space” (nose, trachea, bronchi). Slower, deeper nasal breaths maximize alveolar ventilation and minimize wasted air, ensuring more fresh oxygen reaches the alveoli for transfer into the blood (Dominelli & Sheel, 2024; Stickland et al., 2013).
• Gas Exchange:
  Oxygen moves from the alveoli into the bloodstream by passive diffusion, while carbon dioxide moves out. Efficient gas exchange depends on matching ventilation (airflow) to perfusion (blood flow) in the lungs. Well-ventilated alveoli that are also well-perfused allow for optimal gas exchange (Petersson & Glenny, 2014).
• Ventilation-Perfusion Matching:
  During exercise, both ventilation and blood flow increase. Your body recruits more capillaries in the lungs and redistributes blood to ensure as much of the lung as possible is used for gas exchange. This helps maintain high oxygen levels in the blood, even as demands rise (Dominelli & Sheel, 2024; James, 2023).
• Circulation and Oxygen Delivery:
  Once oxygen enters your blood, it binds to hemoglobin in red blood cells and is pumped by the heart to your working muscles. Efficient breathing and gas exchange support higher cardiac output and better muscle oxygenation, which are critical for both endurance and sprint performance (Kalliokoski et al., 2005).
• Blood Vessel Adaptation:
  With exercise, blood vessels in the lungs dilate and recruit previously closed capillaries to accommodate increased blood flow. This increases the surface area for gas exchange and helps keep the alveoli dry and functional, even at high intensities (Stickland et al., 2013).

HOW TO BREATHE: NOSE, LIGHT, SLOW, DEEP (NLSD)

• Nose: Always breathe in and out through your nose whenever possible, during both rest and exercise.
• Light: Light: The objective is to enhance carbon dioxide (CO₂) tolerance, which in turn facilitates a reduction in overall minute ventilation (MV) during physical exercise. This is achieved by decreasing respiratory rate (RR) and maintaining a reduced or normal tidal volume (TV), resulting in a lower total volume of air breathed per minute. (MV = RR × TV)
• Slow: Maintain a slow, controlled breathing rate to maximize alveolar ventilation and gas exchange.
• Deep: Direct each breath deep into your lower lungs by engaging your diaphragm, not just your upper chest.

By breathing nose, light, slow, and deep, you:

• Enhance alveolar ventilation and minimize wasted air
• Improve gas exchange and oxygen uptake
• Support optimal blood circulation and oxygen delivery to working muscles
• Reduce dehydration and airway irritation
• Create the internal environment for better endurance, faster recovery, and overall resilience

In summary:
Reducing minute ventilation during exercise allows cyclists to breathe more efficiently, meaning they’re not wasting energy on excessive or ineffective breathing. This lowers the oxygen demand of the respiratory muscles, so more oxygen and blood flow are available to the legs and working muscles. Efficient breathing improves gas exchange, supports better oxygen delivery, and ultimately leads to greater endurance, reduced fatigue, and faster recovery.
(Kalliokoski et al., 2005; Petersson & Glenny, 2014; Stickland et al., 2013)

SPORT: STRESSOR EXERCISES, HYPOXIC ADAPTATION, AND SPRINTING

For 23 years, Patrick McKeown has trained athletes in nasal breathing, mind, and functional breathing, but also in the use of stressor exercises involving breath holds after exhalation. These are performed during movement and are sometimes called dynamic apnea or hypoventilation training. They are fundamentally different from breath holds performed in other breathing techniques, such as the Wim Hof Method, which involve a period of hyperventilation followed by breath holding. The Oxygen Advantage breath hold exercises are designed to simultaneously lower oxygen and increase carbon dioxide, creating a potent training stimulus.

What is Involved in Dynamic Breath Holds?

During a dynamic breath hold:

• CO₂ levels rise and O₂ levels fall:
  By holding the breath after a normal, relaxed exhalation (not after a deep breath in), you quickly create a controlled state of “air hunger.” This causes a significant increase in blood carbon dioxide (CO₂) and a marked drop in blood oxygen saturation (O₂).
• Trains chemoreceptors:
  The strong air hunger trains your chemoreceptors to become less sensitive to CO₂, which over time increases your CO₂ tolerance and reduces the urge to over-breathe.
• Physiological adaptations:
• Improves your body’s buffering capacity against acid buildup in muscles, helping to delay lactic acid accumulation and fatigue (Yamamoto et al., 1988).
• Stimulates adaptations similar to high-altitude training, such as increased red blood cell production and enhanced oxygen delivery to muscles (Bouten et al., 2024).
• Reduces oxidative stress and blood acidosis, as shown in studies on dynamic apnea (Joulia et al., 2003).
• Performance benefits:
  With repeated practice, you’ll be able to maintain a calm, efficient breathing pattern even under intense effort, improve your ability to tolerate breathlessness, and enhance both aerobic and anaerobic performance.

Key points:

• Exhale-hold breath holds are not a test of willpower or a competition, but a targeted training tool to safely induce hypoxia and hypercapnia.
• The length of each breath hold is guided by the strength of your air hunger, not by a fixed time.
• Over time, this practice leads to a reduced ventilatory response to CO₂, greater CO₂ tolerance, and improved day-to-day breathing patterns.

Stopping ventilation has been shown to initiate the diving response at rest as during exercise (Lin, 1988; Lindholm et al., 1999; Lindholm and Lundgren, 2009). Apnea alone during physical exercise is sufficient to trigger the diving response, and it can be modulated by immersion, water temperature, hypoxia, physical activity, and training.

Sprinting and Repeated-Sprint Training

Sprinting is a cornerstone of cycling performance, whether in breakaways, final sprints, or repeated surges during races. Recent research has shown that sprint ability can be powerfully enhanced by combining sprints with breath holds—specifically, repeated-sprint training in hypoxia induced by voluntary hypoventilation at low lung volume (RSH-VHL).

• Performance Adaptation: Woorons et al. (2007; 2020) showed that repeated cycling sprints in hypoxia induced by voluntary hypoventilation improved repeated sprint ability, muscle perfusion, post-exercise oxygen uptake, and lactate clearance, without reducing power output.
• Meta-analysis Support: A 2025 meta-analysis by Précart and colleagues showed that repeated-sprint training in hypoxia induced by voluntary hypoventilation at low lung volume (RSH-VHL) provides significant gains in fatigue resistance and glycolytic contribution compared to normal breathing repeated-sprint training.
• Protocol: Involves exhaling down to functional residual capacity, then holding the breath over an entire all-out sprint (typically ≤8 seconds), followed by normal breathing during recovery.
• Benefits for Cyclists: This method can achieve blood oxygen saturations as low as 88–91%, similar to simulated altitudes of 3000 meters. Sprinting in hypoxia with voluntary hypoventilation improves repeated sprint ability, muscle perfusion, and recovery between efforts.

RECOVERY AND SLEEP: THE OVERLOOKED PILLAR

Sleep is a critical pillar of recovery for cyclists. Multiple studies have shown that even a single night of sleep restriction after heavy exercise can significantly impair time trial performance and recovery. Chronic sleep deprivation leads to moderate but meaningful reductions in endurance performance, especially for efforts lasting longer than 30 minutes.

Cycling-Specific Evidence:

• A 2023 study demonstrated that restricting sleep to just 3 hours between consecutive days of exercise significantly reduced mean power output during both sprint and endurance cycling tests, and led to lower overall feelings of wellness and mood (Dean et al., 2023).
• Another study found that extending sleep by 90 minutes for three days improved cycling endurance performance by 3%, while restricting sleep by 30% led to a 3% decline in time trial performance (Yeager, 2019).
• Up to 41% of elite and junior cyclists have dysfunctional sleep quality, which is linked to impaired recovery and performance (Javaloyes et al., 2024).

Professional Cyclists and Stage Races:

• Data from the Tour de France show that professional cyclists often struggle to get enough restorative sleep during stage races. While total sleep time may not drop dramatically, sleep efficiency and REM sleep decrease, and heart rate variability declines over consecutive days of racing—directly affecting recovery and subsequent performance (de Neef, M., 2024).

General Athletic Performance:

• Sleep deprivation increases reaction time, decreases concentration, and impairs motor coordination, raising the risk of accidents and injuries (JS Cycling Training, 2024; Taheri & Arabameri, 2012).
• Lack of sleep also negatively affects anaerobic endurance and speed (Kong et al., 2025), along with recovery from physical exertion, leading to increased recovery time, poorer performance in stage races, and greater susceptibility to injuries (Charest & Grandner, 2020).

Magnitude of Impact:

• Improved sleep has been shown to boost cycling performance by 5–15%—a gain far greater than any equipment upgrade (Billyard, 2023).
• These improvements are attributed to better muscle recovery, hormonal regulation, cognitive function, and mood.

Key Takeaway:
Prioritizing sleep – alongside breath training – should be a cornerstone of every cyclist’s recovery strategy. Even modest improvements in sleep quality and duration can yield substantial gains in performance, wellness, and resilience.

• Nasal breathing during sleep promotes deeper, more restorative sleep by stabilizing breathing, increasing parasympathetic activity, and improving heart rate variability (Watso et al., 2023).
• MyoTape and nasal dilators can help ensure nasal breathing during sleep, further enhancing recovery and sleep quality.
• Achieving a high BOLT score and the ability to downregulate the body and mind (activate the rest-and-digest response) are key to improving sleep quality and waking up more alert.

MIND: FOCUS, FLOW, AND THE OXYGEN ADVANTAGE® PILLARS

Breath training is not just physical – it is also psychological. The Mind pillar of Oxygen Advantage® emphasizes the role of breath in regulating focus, attention, and emotional resilience.

• Nasal and slow breathing activate the parasympathetic nervous system, reduce anxiety, and support entry into flow states – where attention is fully devoted to the task and performance is optimized.
• Mental resilience is essential for cyclists, who must maintain concentration and composure under fatigue and stress.

Practical Steps for Cyclists

• Assess your BOLT score:
  Begin by measuring your Body Oxygen Level Test (BOLT) score – a simple breath-hold test after a normal exhalation. Aim for a score of 25 seconds or more, which indicates functional breathing and good CO₂ tolerance. If your BOLT score is lower, it signals higher sensitivity to carbon dioxide and a tendency toward rapid, shallow breathing. Improving your BOLT score should be a priority, as it reflects your body’s ability to tolerate CO₂ and resist breathlessness during exercise.
• Adapt to nasal breathing:
  Transition gradually by starting with nasal breathing during low-intensity rides, warm-ups, and cool-downs. If you experience nasal congestion or narrow airways, use nasal dilators to improve airflow. As your CO₂ tolerance and BOLT score improve, progressively increase the intensity and duration of nasal breathing during training. This adaptation process helps your body become more comfortable with higher CO₂ levels, supporting calmer, more efficient breathing even at higher workloads.
• Incorporate breath holds:
  Regularly practice post-exhale breath holds (dynamic apnea) during warm-ups, low-intensity sessions, and sprint intervals. These exercises expose your body to higher CO₂ and lower oxygen, training your chemoreceptors to become less sensitive to CO₂. Over time, this reduces your urge to over-breathe, delays the onset of breathlessness, and enhances your ability to perform repeated sprints and high-intensity efforts.
• Train the diaphragm:
  Practice slow, deep nasal breathing to fully engage your diaphragm. This not only improves lung capacity and breathing efficiency, but also supports better CO₂ retention and tolerance. Consider using inspiratory muscle training devices such as SportsMask to add resistance and further strengthen your respiratory muscles.
• Prioritize sleep and recovery:
  Use MyoTape or nasal dilators to maintain nasal breathing during sleep, which supports deeper, more restorative rest and better overnight CO₂ regulation. After training, practice slow, nasal, diaphragmatic breathing to activate your parasympathetic nervous system, speed recovery, and optimize heart rate variability.
• Focus on the mind:
  Incorporate breathwork and mindfulness techniques to train your ability to sustain attention and manage stress. This mental training, combined with improved sleep quality and CO₂ tolerance, helps you enter flow states, maintain composure under pressure, and maximize both physical and cognitive performance during rides and races.

Improving your CO₂ tolerance through these steps not only enhances your breathing efficiency and endurance but also supports better oxygen delivery to your muscles, greater resistance to fatigue, and a calmer, more focused mind—giving you a true performance edge in cycling.

For more information on Oxygen Advantage® breathwork courses please visit: Online Breathwork Class

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