Simple Breath-Hold During Warmups Can Instantly Improve VO2max Over 10%

Research article citation:

Wang, W., Wu, D., Wang, H., Zhang, Z., Jiang, X., Li, S., Shi, Y., & Gao, X. (2024). Acute Effects of Breath-Hold Conditions on Aerobic Fitness in Elite Rugby Players. Life (Basel, Switzerland), 14(8), 917-. https://doi.org/10.3390/life14080917

Let's get right to it. Straight to application on why having half a dozen breath holds during an easy aerobic warmup could supercharge your VO2max transiently for instant benefits in subsequent training/ event. Below is the end of the story, what really matters in the real world. Following the application will go into much further details of the "whys" of the explained radical physiological changes observed in elite male rugby players.

APPLICATION:

The authors concluded dry dynamic BH warmups to be the most effective protocol to enhance subsequent intense cardiovascular exercise and found no obvious contradictions from their observations and what other studies with BH and athletes have concluded. The results of this study can easily be applied. No special equipment is required, and the benefits are instant. The protocol is extremely easy to follow. All one must do is an easy dynamic (moving aspect) warmup with minimal resistance (simply walking briskly or a slow jog) while performing BH’s protocol below:

1)     hold their breath at the end of a natural exhale until beginning to feel a strong urge to breathe.

2)     Rest for 30 seconds and repeat for a total of six rounds.

Dry dynamic BH protocol can easily be woven into a pre-existing warmup routine. The study found no ill health effects. Furthermore, if such significant improvements in VO2max were noted in these elite young athletes (mean 8L/min improvement) it could be hypothesized that less conditioned athletes might see the same or even greater changes in VO2max. 

SUMMARY:

Current research has provided little conclusive evidence for the incorporation of various breath hold (BH) techniques and exercises to acutely improve exercise performance. Numerous methods of apnea protocols have been examined for how they can affect exercise performance, namely in endurance situations. However, BH exercises seem to vary in their effect depending on whether BH occurs with the face in water (wet) or without being submersed (dry) or resting state (non-exertional) or active (concurrent with exercise). Some studies have examined single static BHs before measuring effects on athletic performance while others study multiple sets of BHs. Therefore, determining which interventions of BHs have yet to be discovered.

A main hypothesis of why BH exercises can cause acute athletic benefits has been attributed to the “diving reflex” (DR) and its systemic physiological effects. However, the way to optimize this effect has not been well established plus possible negative effects via inducing hyperactivity of the parasympathetic nervous system which would decrease the preceding bout of exercise performance. Prior research has found static (individuals are at rest) BH and dynamic (individuals are exercising at some capacity) BH drills have vastly different systemic effects. Dynamic BH drills have demonstrated the body’s ability to use the DR to create more efficient muscular contraction, however, no studies have compared the static vs dynamic among the same population at the same time.

The main objective in this study is to examine how utilizing different BH protocols in a practical manner among elite athletes will affect strenuous activity that immediately follows. The hypothesis was that wet and dry BH and dynamic and static BH affect performance and the cardiopulmonary system in different way among high performing athletes.

Excellent thought was given to the study design. Eighteen elite male athletes (nationally ranked performers) with a mean age of 23.5 +/- 1.8. The independent variables in the study are various versions of BH protocols. Five independent variables were tested: Warmup with no BH (served as the control), dry static BH, dry dynamic BH, wet static BH (water temp 10-11 Celsius), and wet dynamic BH. The dynamic warmup was on a stationary bike that provided equal wattage for all sessions and all BH protocols. Each athlete was randomly assigned to utilize a different BH protocol each week until all five protocols had been performed. The athlete would use a particular type of BH for ten minutes as their warm-up before blood collection and exercise testing analysis. For example, in week one “athlete-A” performed one version of a BH method. The second week, the athlete would randomly perform another version on BH as a warmup until all five versions of BH’s had been performed.

All BH warmups required the individual to hold a maximal end-expiratory breath and repeat six times with 30 seconds of normal breathing for recovery between each hold.  Following the warmup, exercise performance analysis was always performed on a stationary bike using a ramp-style method until the athlete reaches 90% of predicted max HR, or sustained HR for two minutes or reduction in oxygen uptake occurred. Notable controlled variables consisted of the following: testing occurred between 9:30-11AM for all test days; abstinence from alcohol and/or caffeine 48 hours prior to test day; eight hours of sleep minimum the night before test day; participants wore the same exact clothes and shoes throughout the study; all participants had no previous BH, hypoxic training, or travel to high-altitudes in last 6 months.

Critical variables were changes in VO2max, peak heart stroke volume, peak heart rate, peak cardiac output, COP (cardiopulmonary optimal point), and blood analysis (HCT and Hb) via fingertip prick. The hypothesis was various BH protocols would elicit heterogenous changes in these critical variables and therefore more performance enhancing BH warmups could be determined. The set-point by which change was measured was any differences observed from the athlete’s standard ten-minute warmup without using a BH protocol.

Critical results demonstrated that dry, wet, static, and dynamic BH warmups do not equally affect the subsequent exercise performance. Dry dynamic BH was explained to be more performance enhancing of the warmups due to sympathetic autonomic modulation.

ANALYSIS/ CRITIQUE:

This study was the first examine multiple BH protocols repeated by the same elite athletes and analyze immediate effect on intense cardiorespiratory exercise. The main problem of evaluating how various BH protocol unequally affect physiology and high effort performance was significantly resolved with an obvious BH protocol that positively affected critical variables. The authors were able to confidently report that dry dynamic BH warmups improved max VO2, max stroke volume, decreased COP, increased HGB compared to the four other tested warmups. Dry dynamic warmup is also more practical compared to wet BH warmups thus improving applicability.

One major conclusion of the authors was that dry dynamic BH were most superior in improving VO2max. Their hypothesis of why this occurs is supported by research on sympathovagal modulation of cardiovascular performance as noted from three separate studies within the last 20 years. The COP critical value that was positively influenced by dry dynamic BH warmup was supported by two research studies suggesting the phenomenon is likely be due to the body having a higher PaCO2 threshold by priming the body to higher PaCO2 before strenuous exercise; dry dynamic breathing practically acts like highly specific warmup for the arterial blood gas homeostasis. Another explaining given why VO2max might have improved more notably in BH warmups is research linking BH to boosting glycolysis pathways. 

Furthermore, since dry dynamic BH demonstrated the most significant increase in stroke volume, this factor is also a probable explanation why this same group had the most significant improvement in VO2max; research was provided which hypothesized that BH prolonged filling time and increased cardiac contractility explaining increases in stroke volume.   Lastly, four references were given how BH has been shown to increase erythropoietin, HGB and augment erythrocyte reserves (notably from the spleen) which can explain why BH warmups affected hematologic data. Fifty-five references were used in support of the author’s research. These were peer reviewed and majority were from the past 20 years.

Further areas of research would be to evaluate the effect of BH warmups on non-elite athletes, older demographics (i.e. >40 years old), how long the acute effects last before intense exercise begins, and how long intense bouts of exercise can be sustained before physiological and performance metrics resume to normal homeostasis.