Testosterone and breathing: It’s not just a man’s hormone.

Testosterone, a hormone primarily associated with men, impacts our breathing. I’ve already looked at the hormones, oestrogen and progesterone, which are generally associated with women. Women produce testosterone just as men produce oestrogen and progesterone. The reason the impact of testosterone is greater in men is that their levels of this hormone are much higher. Even so, many of the effects of testosterone are applicable to women and men.

The impact of testosterone on breathing is multifaceted. The science indicates that it operates in several different ways, interacting with a number of bodily functions. Because of this, there are not always clear answers about how testosterone affects our breathing.

Take, for example, testosterone and its effect on CO2 intolerance—the strength of a person’s response to rising CO2 levels in the body which is also known as CO2 sensitivity. Research indicates that testosterone can increase CO2 sensitivity and, therefore, is a driver of breathing (our desire to breathe/air hunger). There is also research that indicates testosterone may decrease CO2 sensitivity. How is this possible? There are many theories, including that testosterone:

• may influence neuromodulation (turning the strength of nerve signals up or down). If the signal is turned down, the drive to breathe will be reduced. If it’s turned up, the drive to breathe will increase

• interacts with other hormones, including cortisol (known as the stress hormone). This interaction may influence stress-related breathing patterns: the speed and depth of our breath

• is also linked to the modulation of our autonomic nervous system (ANS). That is, it may influence how sensitive our body’s response to CO2 is. In one individual, the ANS may have a much stronger stress response than the equivalent level of CO2 in another person.

Because of the complexity of overlapping systems in the body, as well as differences in biological sex, individual physiology, and research design, there are no definitive scientific findings that establish why testosterone can both decrease and increase CO2 intolerance depending on the individual. What is certain is that testosterone does have an influence.

Testosterone is associated with growing and maintaining muscle. This is one of the key reasons why men (generally) are bigger and stronger than women. If you have higher levels of testosterone, then you may have a stronger diaphragm and intercostal muscles (the small muscles between the ribs). This may increase your lung capacity and give you more efficient respiration.

Women with high levels of testosterone may gain these benefits while their female peers do not. For women, improved muscle tone provided by testosterone may help maintain breathing mechanics, especially when oestrogen and progesterone levels drop permanently post-menopause.

Testosterone is also associated with the production of erythropoietin (EPO). EPO increases the production of red blood cells and hemoglobin. This improves the oxygen-carrying capacity of the blood. Women with high levels of testosterone will benefit from this capability. This benefit is why EPO is a banned performance enhancer.

Even so, more testosterone is not always a good thing. High levels of testosterone are also associated with an increased risk of sleep apnea, or sleep apnea getting worse, particularly in men.

Testosterone isn’t a primary driver of breathing like CO2 intolerance or progesterone, but it modulates the systems that interact with those drivers. It also influences secondary systems, e.g., muscle growth and strength, that can influence breathing. These effects occur in both men and women, but are more prominent in men because their testosterone levels are higher.

Disclaimer

This blog is for informational purposes only. It is not medical advice. Always consult a healthcare professional for personalized guidance and treatment.