Yawning During Exercise? The Possible Causes Might Surprise You

Why do people yawn while exercising?

I had an interesting question from a participant in one of my group exercise classes the other day. She said that she tends to yawn uncontrollably during exercise class, quickly assuring me that my classes really aren't boring! The others in the class seemed sure that it was due to either fatigue or a lack of oxygen, but I decided to do a bit of research on the subject to satisfy my own curiosity.

Why do people yawn?

Yawning is a phenomenon that people experience before they are born, beginning at around eleven weeks after conception, yet scientists have not sorted out the complexities of this normal human action. Many theories have been tested with some interesting and sometimes mixed results. Here are a few...

Yawning and Oxygen Requirements

Although one common theory linked yawning with either low levels of oxygen or high levels of carbon dioxide, a study found that neither triggered yawning. They put the theory to the test by administering either 100% oxygen or gas mixtures containing 3% or 5% carbon dioxide, which is higher than normal CO2, and compared yawning rates with a control group. Although breathing rates were affected, yawning rates did not change. Studies that looked at exercise that doubled participant's breathing rates did not seem to change yawn rates either.



Yawning and Fatigue

Yawning is a common response to sleepiness, as detailed in the April 2007 Behavioral Brain Research article entitled The functional relationship between yawning and vigilance by Adrian G. Guggisburg et al. Sleepiness or exhaustion might be obvious in the person who suffers from insomnia or who knowingly does not get enough sleep, but those who seem to have an adequate amount of sleep could also be suffering from sleep disturbances of which they are unaware.

Many people suffer from sleep apnea, a condition in which the person stops breathing and then starts again while asleep. Another common condition that can disrupt sleep is periodic leg movement disorder (PLMD), a condition in which the person's legs twitch or move while the person sleeps. Those with sleep apnea or PLMD may wake up exhausted and tend to fall asleep during the day despite sleeping a normal amount of time due to repeated disturbances in the sleep cycle. Fatigue has quite a few other potential sources, such as an infection, food allergies, thyroid problems, and a diet lacking in necessary nutrients.

Yawning and Core Temperature Regulation 

According to a September 2008 Psychology & Behavior article by Andrew C. Gallup and Gordon G. Gallup entitled Yawning and Thermoregulation, yawning may be a way for the body to cool itself when other measures fail. Excessive or unusual yawning tends to occur with conditions that are commonly associated with a higher core temperature, such as multiple sclerosis, migraine headaches, stress, anxiety, sleep deprivation, and certain medications that may slightly elevate the body's temperature.

The core temperature typically rises during exercise, so yawning during an exercise class might indicate that the person's core temperature is rising and therefore the body is trying to cool itself. However, more studies specifically looking at thermoregulation and yawning would be helpful.

Medications That May Cause People to Yawn - Photo from Wikimedia Commons

Yawning and Medications

Several medications may be associated with yawning. According to the January 2007 Acta Psychiatrica Scandinavica article entitled Do your patients suffer from excessive yawning? by A. M Gutiérrez-Álvarez, the following medications tend to be associated with excessive yawning:

• selective serotonin reuptake inhibitors
• levodopa
• dopamine agonists
• MAO B inhibitors
• morphine
• methadone
• buprenorphine
• dextromethorphan
• benzodiazepine
• lidocaine
• flecaine 

It is interesting to note that in the above article, excessive yawning was shown to disappear with a decrease in dosage of the medication, so drug-induced yawning may be related to dosage.

Why Do People Yawn When Someone Else Yawns? - Photo by Scobull at Wikimedia Commons

Contagious Yawning

When seeing another person yawn, it is very common to yawn in response, but this does not happen every time a person sees someone else yawn. Why?

Humans as well as some mammals yawn, and this behavior may serve as a type of communication. According to the July 2010 Neuroscience & Biobehavioral Reviews article entitled Why do we yawn? by Adrian G. Guggisberg et al, yawning may serve to tell others that one is sleepy, bored, or perhaps experiencing mild psychological stress.

An article published in the 2011 PLoS ONE publication entitled Ingroup-Outgroup Bias in Contagious Yawning by Chimpanzees Supports Link to Empathy by Matthew W. Campbell and Frans B. M. de Waal found that chimps tended to yawn more when seeing someone familiar yawn than they did when seeing someone unfamiliar yawn. Perhaps folks who have common ground may be more likely to yawn when seeing someone familiar yawn, such as might be the case with an exercise class in which participants know one another.

The May 2011 Journal of Ethology article entitled The daily time course of contagious and spontaneous yawning among humans by Fiorenza Giganti and Iole Zilli found that test subjects were more likely to experience contagious yawning in early morning and late evening. Exercising at these times might mean that one is more likely to spontaneously yawn or to "catch" a yawn from another participant.

Yawning as a Symptom of Other Health Conditions

According to the NIH article Yawning – Excessive last updated 1/31/2011, excessive yawning could be the result of a vasovagal response, indicating a heart problem. Excessive yawning such as this may be more likely to persist throughout the day and not just during exercise. Yawning due to a medical condition in particular would warrant an evaluation by a healthcare professional.

Yawning During Exercise

I won't take the frequent yawning in my exercise classes personally, but I decided to publish my resulting research in order to help others out there who might be yawning while working out. The answer might not be simple or easily found, but knowing possible causes can help to focus efforts for someone who is trying to stop yawning excessively.

As with all of my articles, this information is not medical advice and anyone experiencing health issues should discuss those issues with his or her healthcare provider.

Related articles:

• Does Sleep Play a Role in Weight Gain and Weight Control?
• Exercise May Improve Cholesterol Ratio and Lower Triglycerides
• Walking – a Simple, Effective, Inexpensive Exercise

Visit the Fit Tips 4 Life site map to see other fitness articles by Katrena.