Episode 194: Breathwork for VO2 Max/Nina Takashima takes a bow

A brief synopsis of the episode's main discussions and takeaways as well as extended references

Author

Jeff Sankoff
April 10, 2026

Can working on how you breathe have an impact on how you perform? It sounds a little too good to be true and of course, it is.

Table of Contents

Breathwork for modifying VO2 Max

Breath work is often promoted as a way to improve aerobic performance, but its direct impact on VO₂max is nuanced. VO₂max reflects the integrated capacity of the cardiovascular system—cardiac output, oxygen delivery, and muscle extraction—so it is primarily improved through endurance training rather than breathing techniques alone.

That said, targeted respiratory training can play a supportive role. Inspiratory muscle training (IMT), using devices or resisted breathing drills, strengthens the diaphragm and accessory breathing muscles. This can reduce the relative effort of breathing during exercise and delay the onset of respiratory muscle fatigue. In turn, this may limit the “respiratory steal” phenomenon, where blood flow is diverted from working limbs to fatigued breathing muscles at high intensities.

Breath work may also improve ventilatory efficiency—how effectively an athlete exchanges oxygen and carbon dioxide at a given workload. Techniques emphasizing controlled nasal breathing or slower respiratory rates can enhance tolerance to elevated carbon dioxide levels, potentially improving comfort and pacing during submaximal efforts. (Though not translated to demonstrable performance benefits).

However, gains in VO₂max itself are typically small or indirect. The primary benefit is improved endurance performance through better breathing economy, reduced perceived exertion, and enhanced fatigue resistance. In practice, breath work is best viewed as a complementary tool layered onto a well-structured aerobic training program rather than a primary driver of VO₂max improvement. One particular area in which breath work may actually be better supported is in relieving anxiety in the lead up to a race. For that specific purpose, there is some evidence to suggest benefit.

Nina Takashima moves on from TDP intern to MD/PhD student

Nina Takashima has been one of two stellar interns on the TriDoc Podcast for more than two years but like those who came before her, the time has come for her to move on to the next phase of her life. Nina took some time to chat with me about embarking on an MD/PhD program at the University of Michigan in the fall and shared what being an intern for the program was like. She told me what she enjoyed learning about and what subjects surprised her. Best of all, she has left the podcast in capable hands by finding a replacement in the form of yet another Grinnell College swimmer! Sara Lopez will step into Nina’s shoes and try to live up to her high standards that she set in the coming weeks.

We wish Nina all the success in the world in her new adventures.

Episode Takeaways:

  • Nina, my superstar intern, is off to the University of Michigan for an MD/PhD program, and honestly, we’re all going to miss her. Way to go, Nina!

  • Breathwork is a hot topic, but it probably won’t boost your VO2 max. But hey, it might help you chill out before that big race!

  • If you’re feeling anxious before a race, breathing techniques can help calm those nerves.

References used for the MMB

Summary:

  • Breathwork is the intentional control of breathing, which is done with the purpose of influencing one’s mental and/or physical state

  • There are many different patterns of breathing, some of which have more evidence than others

  • According to methodologies in published articles, the breathing technique that utilizes diaphragmatic inhalation with pursed-lip exhalation appears to be helpful during exertion

  • Breathwork generally seems to help relax one’s body and improve breathing efficiency, CO2 tolerance, and enhance respiratory muscle strength

  • In a study of untrained individuals, diaphragmatic breathing showed a slight increase in VO2max

  • However, despite many web articles advertising breathwork as a means to improve VO2max and performance, the scientific evidence remains weak, particularly for trained individuals

  • An apnoea training meta-analysis study shows that breath-hold training increased blood lactate levels, suggesting improved anaerobic capacity, but did not change VO2max

  • Additionally, in recreational runners, CO2 tolerance was observed, but no improvements in VO2max were observed

  • Inspiratory muscle training in trained rowers also improved respiratory strength without changing VO2max

  • Overall, breathwork may support anaerobic performance, but does not seem to affect VO2 max and aerobic performance in the short term

  • Despite these findings, it’s important to recognize that there are still benefits to breathwork, including improved breathing control, anaerobic performance, and respiratory muscle strength/endurance

Breathwork for Beginners: What To Know and How To Get Started 

Cleveland Clinic article uploaded May 19, 2023

Key Points:

  • Cleveland Clinic defines breathwork as breathing techniques that intentionally channel and focus on the breath

  • Eastern medicine have put breathing techniques to practice for thousands of years

  • mental/emotional stress can cause adverse physical effects on the body

  • Breathwork is one stress management technique that helps to activate your parasympathetic nervous system, calm you/move you away from fight-or-flight mode, and de-escalate or de-stress 

  • Types and techniques:

    • Diaphragmatic breathing --- engage muscles at the base of the lungs

    • Box breathing --- 4 counts of the following: inhale, hold, exhale, hold

    • 4-7-8 breathing --- inhale 4 counts, hold 7 counts, exhale 8 counts; 

    • Alternate nostril breathing --- while scientific evidence is lacking, it is historically said to clear energy blockages and bring inner balance; studies suggest it may sharpen focus/energy

    • Pursed lip breathing --- nasal inhalation and pursed lip exhalation; can make exertion easier during activities like lifting and climbing stairs

    • Lion’s breath --- stick tongue out during exhalation and make ‘haaa’ sound to relieve anxiety; minimal scientific research to back it up

    • Five-finger breathing --- traces around fingers with a finger on your other hand

    • Holotropic breathwork --- rapid, controlled breathing led by facilitator to cope with emtal health

    • Breathwork meditation --- combines elements of deep breathing and meditation

  • Article notes that scientific research and/or evidence is limited or not found for many of these techniques

The Different Types Of Breathwork (Overview, Origins & Methods)

Web Article by Johannes Egberts on November 19, 2024

Key Points:

  • Breathwork, the manipulation of breath, has become popularized as a holistic practice among those seeking stress relief, improved physical, emotional, and/or spiritual well-being

  • Article notes that the benefits of breath work are supported by testimonies and research

  • There are several different types of breathwork including:

    • Diaphragmatic breathwork --- nasal breathing into the abdomen, pursed lip exhalation 

      • Stimulates vagus nerves and helps to increase oxygen 

    • Buteyko breathwork --- deep nasal inhalation, calm exhalation, pinch nose to hold breath

      • Main idea is that people typically breathe too much

    • Circular breathwork --- maintains continuous breathflow without interruptions

    • Holotropic breathwork --- modern method to facilitate altered states of consciousness through rhythmic breathing, typically done in groups with a person who guides the breathing 

    • Pranayama breathing --- use finger to block one nostril while breathing in, momentarily pause breath, and exhale through the other nostril 

    • Wim Hof breathwork --- contemporary breathwork combining breath control, cold exposure, and meditation to improve physical endurance, immune system, and build mental resilience

  • Different breathwork can be utilized for various purposes: 

    • Stress/anxiety management: diaphragmatic or buteyko

    • Emotional release/catharsis: holotropic or circular

    • Spiritual practice with deep philosophical roots: pranayama

  • Article promoted breathwork classes at Breathless

VO₂ Max and Breathwork for Longevity and Performance

Article based on a 2023 AIM Newspaper Article by Tara Kulikov 

Key Points:

  • Breathing is defined as the natural intake of O2 and expulsion of CO2 that occurs without pathology

  • VO2 max, which can be measured using a gas analyzer, is the maximum amount of oxygen consumption that is possible during an exercise

  • Research indicates that VO2max is associated with longevity

  • The article notes that as you go from low fitness individuals to just below average, just above average, and elite athletes, their mortality is reduced by 50%, 60-70%, and fivefold over a decade

  • The article notes that VO2max can be improved through intentional exercise

  • The O2 and CO2 homeostasis is important to consider, as disturbances to this system can influence disease development 

  • This can be regulated through breath work, which is often emphasized in martial arts, yoga, and Chinese medicine

  • This article defines breath work as “conscious, controlled breathing done especially for relaxation, meditation, or therapeutic purposes”

  • According to the article, research shows that mental and physical health benefits can be obtained from any technique that slows the breath to less than 10 per minute

  • Nasal breathing is typically preferred over mouth breathing

  • An exercise physiologist can inform you of the correct training zones and exercise programs

Effects of apnoea training on aerobic and anaerobic performance: A systematic review and meta-analysis

Asis-Fernandez et al. 2022

Key Points:

  • Apnoea training, or breath-hold training, has demonstrated benefits for divers to withstand extreme hypoxaemic/hypercapnic conditions

  • Breath-hold divers (BHD) increase their gas storage capacity through thoracic stretching and glossopharyngeal insufflation

  • The effects of apnoea training on performance have been studied in various athletic contexts

  • This paper was the first systematic review and meta-analysis of the longitudinal (2-22wks) effects of voluntary apnoea training (ApT) on aerobic and anaerobic performance measured by VO2max and peak blood lactate levels

  • The study showed that longitudinal ApT increased peak blood lactate relative to control normal breathing (NB) in recreational athletes, suggesting that ApT may have the potential to enhance anaerobic performance by increasing blood lactate levels in high-intensity intermittent sports 

  • However, no significant increase in aerobic marker, VO2max, was observed with ApT

  • Great variability in training methods was identified, so methodological limitations must be considered when assessing these findings

  • Furthermore, the paper notes that physiological adaptations acquired by the BHDs go beyond isolated breath-hold stimulus (i.e. stretching, endurance, inspiratory muscle training, swimming, glossopharyngeal insufflation, etc.), so other interventions likely confound the effectiveness of ApT

Methods: Web of Science, PubMed, and SCOPUS searched. Inclusion criteria included: peer-reviewed journal publications, clinical trials, and healthy humans assessing short-term (≤6 weeks), medium-term (7–23 weeks) or long-term (≥24 weeks) effects of apnoea training…excluding acute warm-up effects of apnoea, that reported aerobic/anaerobic performance markers. Study bias and quality were assessed. 

Results: 192 papers of the initially identified 538 manuscripts met inclusion criteria. 7 studies are included in the meta-analysis. 127 participants (age: 27+/-9 yo). Apnoea training (n=64) and normal breathing (n=63). Mean intervention 8 weeks, frequency of training 3.6 times/week. “Meta-analysis on the included studies demonstrated that ApT increased the peak blood lactate concentration more than NB (MD = 1.89 mmol*L−1 [95% CI 1.05, 2.73], z = 4.40, p < 0.0001). In contrast, there were no statistically significant effects of ApT on VO2max (MD = 0.89 ml*kg−1*min−1 [95% CI −1.23, 3.01], z = 0.82, p = 0.41).”

Effects of breathing exercises on resting metabolic rate and maximal oxygen uptake

Yong et al. 2018

Key Points:

  • This study examined the effects of diaphragm breathing exercise (DBE) and feedback breathing exercise (FBE) on VO2max and resting metabolic rate

  • DBE: Participants placed their hands on their abdomen and inhaled slowly and deeply through the nose by expanding the abdomen (not the chest), briefly held their breath, and exhaled slowly with pursed lips while hollowing their abdomen.

  • FBE: Participants used the TIGER respiratory training device, which is a mouthpiece connected via tube to a rebreathing bag, used to train respiratory muscle endurance.

  • The TIGER device provided visual and auditory cues to guide inhalation and exhalation timing.

  • The study showed that both DBE and FBE could significantly enhance VO2max and DBE could also significantly reduce RMR, suggesting their potential use in clinical applications.

Methods: 38 healthy participants were randomly assigned to the diaphragm breathing exercise (n=21, age 19.71+/-0.78) or the feedback breathing exercise (n=17, age 20.06+/-1.78) group. Maximal oxygen uptake (VO2max) and resting metabolic rate (RMR) were measured. 

Results: Significant differences were found in VO2max before and after DBE and FBE (p<0.05), along with significant differences in RMR before and after DBE (p<0.05). No significant difference in RMR was observed before and after FBE (p>0.05), but there was also no significant difference between groups in both VO2max and RMR.

The Effects of a Short-Term Supplemental Breathwork Protocol on the Aerobic Performance of Recreational Runners

Wolff et al. 2025

Key Points:

  • This study assessed the effects of functional breathing programs on aerobic performance among 16 recreational athletes 

  • Despite observing an increase in VO2max in both FBP and CON groups, the ΔMNRT and ΔMNBVO2 for the FBP group were not different from those in the control group.

  • The study showed a significant change in ΔBOLT (breath-hold time) in the FBP group compared to the CON group, suggesting that FBP may be effective in enhancing the body’s adaptation to chemosensitivity to elevated blood CO2 concentrations and delaying the urge to breathe sooner 

  • While CO2 tolerance and breath-hold capacity may have improved, since no improvements were seen in physical performance-related variables, such as VO2max and running efficiency, between the groups, the changes observed in chemosensitivity may not extend beyond the resting state to exercise conditions

  • In this study, breathwork altered respiratory control, but did not appear to enhance aerobic performance

  • The results of this study may differ among elite athletic populations

Methods: Participants recruited from local gyms and running clubs were randomly enrolled in an aerobic endurance training program with functional breathing (FBP) (n = 8, 34.8 ± 5.1 yrs) or without functional breathing (CON) (n = 8, 29 ± 5 yrs). FBP group underwent daily breathing exercises and nasal-only breathing during low-intensity sessions of the training program. FBP participants with BOLT time <30s given exercise to reduce tidal volume and stimulate short mild hypercapnic response (85-94% SpO2). BOLT time >30s given breathing exercises to stimulate same effect for a longer period. Performance measured before and after 4wks running intervention. BOLT Test (breath-hold test) used to measure chemosensitivity. Duration of comfortable breath hold following exhalation. Graded exercise test on treadmill used to identify the time and speed at which participants needed to switch to oral breathing (MNRT). Metabolic data also collected at that running speed after mouth tape was removed. Subjects completed remaining time until volitional fatigue was reached,. If not reached byte h end of the fifth stare, treadmill grade was increased. Main outcome variables included MNBVO2 (greatest 15 s VO2 value prior to MNRT), and VO2max (greatest 15 s VO2 value during the GXT). Running economy was measured by analyzing steady-state O2 consumption for the running speeds during each of the last three stages prior to MNRT (using the average VO2 values of the final 15 s of each stage).

Results: No difference in baseline physical characteristics between groups, except age. No outcome variable differences at baseline. Significant group-time interaction observed for BOLT time (p = 0.04; d = 1.13), which increased significantly more for the FBP group compared to the CON group. Significant difference in mean body mass seen, with mass decreasing for FBP by ~1.1kg while mass increased 0.4kg in CON group. VO2max increased in both groups but likely due to running. 

Specific inspiratory muscle training does not improve performance or VO2max levels in well trained rowers

Riganas et al. 2008

Key Points:

  • I only had access to the abstract of this paper

  • The study published in this paper examined the effects of specific inspiratory muscle training (IMT) on the inspiratory muscle strength, VO2max, maximal lactate accumulation (Lmax), dyspnea sensation (perceived level of breathlessness) and 2000m rowing performance of well-trained rowers 

  • The study found that while 6 wks of IMT strengthened inspiratory muscles by 28%, the training did not improve VO2max, dyspnea sensation during exercise, or performance in trained rowers

  • The findings that the breath training does not affect aerobic capacity or performance in trained athletes are consistent with what has been observed among recreationally active populations

Methods: Well-trained athletes dividend to control or treatment group (performed 30min/d of IMT 5x/wk for 6wks) (N=19). All underwent normal rowing training. Participants underwent an incremental treadmill run test to determine VO2max before and after 6wks. Maximum inspiratory mouth pressure measured as well. 2000m rowing ergometer performance evaluation done. 

Results: “Six weeks of IMT significantly (P < 0.05) increased resting PImax. Moreover, inspiratory muscle training increased PImax following the VO2max test in the T group. In contrast, no changes in PImax were observed in the C group during the 6-week period. No significant differences were observed between pre- and post-test values in VO2max, dyspnea sensation, Lmax, and 2000 m race time in both groups.”

Effects of simultaneous aerobic and inspiratory muscle training on diaphragm function, respiratory muscle strength, endurance, and fatigue index: randomized-controlled trial

Celik et al. 2025

Key Points:

  • This study was the first of its kind to assess whether combining aerobic exercise and walking-specific inspiratory muscle training (W-SIMT) improves diaphragm function, respiratory muscle strength, endurance, and fatigue. 

  • The findings showed that combining aerobic exercise and IMT improves inspiratory muscle strength, endurance, and anaerobic performance in a short time, suggesting its potential to support muscle adaptation.

  • Past studies with IMT have reported 8-12% increase in diaphragm thickness and 4% improvement in MIP, but this study showed ~20% improvement in both diaphragm thickness and MIP in the W-SIMP group (p>0.05), which may be due to the combined effects of aerobic exercise and IMT.

Methods: Randomized-controlled study. Healthy participants (N=27) divided into W-SIMT (n=14) or control (n=13). Both groups underwent training (60–80% of maximal heart rate; 3 days/wk for 4 wks). W-SIMT group performed 30 consecutive inspirations with 2-min rest (2 sets) in 50% of the maximal inspiratory pressure (MIP) using an assistive inspiratory muscle training device called PowerBreathe while walking. Diaphragm thickness/stiffness, pulmonary functions, MIP, Maximal Expiratory Pressure (MEP), sustained inspiratory maximal pressure (Pmax), and fatigue index were evaluated before and after 4wk intervention. 

Results: Baseline demographics, respiratory parameters, performance, and anthropometric parameters were comparable in both groups (p>0.05). Significant effect of group × time interaction (F = 28.719, p < 0.001; F = 10.640, P = 0.003) for MIP (cmH2O and %, respectively), Pmax (F = 5.414, p = 0.029) and fatigue index (F = 4.775, p = 0.039) was observed in favor of the W-SIMT group. Significant time effects observed for MIP, MEP, PEF%, diaphragm thickness during inspiration, respiratory muscle endurance parameters (Pmax, Tmax, Levelmax), and average power.

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