Does Exercise Change Your Threshold for Pain?

Exercise has an enormous number of health benefits. If exercise could be packaged into a pill, it would be one of the most prescribed. Regular workouts lower the risk of a long list of health problems including heart disease, high blood pressure, type 2 diabetes, depression and some forms of cancer. Plus, exercise helps relieve stress. Now a new study shows regular exercise may change your pain tolerance.

Exercise and Pain Tolerance

No one likes to experience pain, whether it’s the pain of a headache or the discomfort of a strained muscle. According to a new study carried out by researchers at the University of New South Wales and Neuroscience Research Center in Sidney Australia, exercise can increase your threshold for pain. Although no one enjoys pains, each person experiences it a little differently. How a person perceives pain isn’t just a matter of biology, pain has an emotional component too. It can be impacted by past experiences, especially traumatic ones.

Genetic factors and even hair color may affect how pain is perceived. For example, a study showed redheads have a lower threshold for pain, meaning they’re sensitive to it at a lower level. Some studies show men have a higher threshold for pain but others show pain tolerance is linked with higher estrogen levels. This would suggest that women should have a higher tolerance for pain. So, it’s not clear whether gender is a factor in pain perception. Nevertheless, there’s evidence that it’s possible to “retrain” your brain to tolerate pain better. Exercise could be one way to do that.

In this study, researchers measured pain tolerance in a group of young, healthy volunteers who didn’t exercise regularly but expressed an interest in doing so. To measure their tolerance to pain, they used a blood pressure cuff that was progressively tightened on their arm until they could no longer tolerate the pain. Ouch! Pain tolerance is distinct from pain threshold, the point at which you first begin to feel pain. They also measured pain tolerance in another group of participants who didn’t exercise and didn’t want to.

Over the next six weeks, the volunteers who expressed an interest in exercising began working out on a stationary bicycle three times a week for 30 minutes. The other participants remained inactive. Here’s where it gets interesting. After 6 weeks, researchers brought both groups back into the lab and re-measured their pain threshold. In the group who hadn’t exercise, their threshold to pain was unchanged while the exercising group experienced a significant increase in pain tolerance.

Pain Tolerance and Exercise

Other research shows athletes have an increased pain tolerance. One study found both endurance and strength athletes have a higher tolerance for pain relative to non-athletes although pain threshold was similar between the two groups. So, athletes and non-athletes begin to feel pain at about the same level but athletes can tolerate more pain than non-athletes. This isn’t surprising when you think of sports like football or boxing. Some long-distance runners are able to keep running through the pain of blistered feet, muscles strains and other discomforts just to finish a marathon. Of course, motivation is a factor too.

What’s interesting is this latest study shows moderate exercise, not exercise at an extreme or professional athlete level, may increase pain tolerance. The reason? It may partially be explained by endorphins, opioid-like molecules released by the brain during periods of vigorous exercise. Endorphins released in response to exercise bind to receptors in your brain where they have an analgesic effect, helping to mask feelings of pain and discomfort.

Endorphins also give a sense of well-being. You’ve probably heard of runner’s high, the feeling of peace and calm runners get when they run for a while. Endorphins are one factor believed to be involved in runner’s high. These calming brain chemicals may also be responsible for other health benefits of exercise, including the fact that a workout relieves stress and elevates mood. You can partially thank your endorphins for that!

What’s interesting about this most recent study is researchers measured pain threshold in the participants not immediately after a workout, when you would expect endorphin levels to be high, but later. Endorphins most likely play a role in reducing pain threshold during and immediately after exercise but endorphin release can’t necessarily explain why the participants had a higher pain threshold at other times.

Does Exercise Change Your Brain?

Its possible exercise retrains your brain so it tolerates more pain. When you’re lifting heavy weights or doing high-intensity exercise, there’s a certain amount of discomfort involved. That’s true any time you place your body under stress. You learn to push through the discomfort so your body has to adapt.

Here’s something else to consider. Have you ever whispered a swear word when struggling to do one more rep when your muscles are already burning? A study showed swearing when something is painful increases pain tolerance. According to this study, swearing has an analgesic effect, much like endorphins. Sounds like the people you hear swearing at the gym are doing it for a reason, even if they don’t know it.

The Bottom Line?

One more benefit to working out – it could help you tolerate pain better. Just don’t use your increased tolerance for pain to keep working out when you’re injured. There’s nothing productive about that!

 

References:

WebMD. “What’s Your Pain Tolerance?”
Rev Colomb Anestesiol. 2012;40:207-12 – Vol. 40 Num.03 DOI: 10.1016/j.rcae.2012.05.006.
Psychosomatic Medicine 65 (2): 284-291. doi:10.1097/01.PSY.0000033127.11561.78.
UF Health Communications. “Endorphins allow athletes to push past pain”
Science Blogs. “Swearing increases pain tolerance”
Sports Med. 1992 Jan;13(1):25-36.

 

Related Articles By Cathe:

Why Most People Don’t Exercise – and It’s Not Lack of Time

5 Reasons Exercise is the Closest Thing to a Happy Pill

4 Ways Your Heart Adapts to Aerobic Exercise

 

3 Responses

  • I really enjoyed this article, but found most interesting that even moderate exercise can increase pain tolerance…you don’t have to run a marathon or lift tremendous weights in order to gain the benefit. Very encouraging!

  • I attributed the non-medicated natural child births of both of my kids (8.5 lbs. and 9 lbs. – I was 5’5″ / 120lbs pre-pregnancy) to the fact that I exercised regularly. Natural childbirth takes a good deal of focus and being ‘in tune’ with your body’s capabilities. Exercise was very helpful for the birth process but also helped me in the post partum phase as I was not as fatigued as other friends during that same period. The youngest child was born 26 years ago and I’m still exercising – albeit with a few changes to the intensity and impact level!

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