Many benefits come from regular exercise, including stronger muscles, lower risk of disease and improvement mental health. But a recent study shows that exercise may have another unexpected benefit: It could make us more tolerant of pain.
The study, published in the journal PLOS One, found that people who exercise regularly have greater pain tolerance compared to those who barely exercise.
To conduct their study, the researchers used data from 10,732 participants who participated in Tromso study – a major health and disease study conducted in Tromsø, Norway. The participants were between the ages of 30 and 87, and slightly more than half were women.
Each participant was assessed twice, eight years apart. During each assessment, they answered questions about their physical activity levels and participated in cold press test. This is common method used by researchers to induce pain in a laboratory setting. Participants put their hand in 3°C water for as long as they can. The longer they keep their hand in the water, the higher their pain tolerance.
The researchers found that the more active the participants were, the longer they could keep their hand in the water. In fact, those who were categorized as very active managed to keep their hand in the water for an average of 115.7 seconds compared to 99.4 seconds for the least active participants. The researchers also found that participants who remained active or became more active performed better on average on the second test compared to those who remained inactive.
However, it is worth noting that over the eight years between assessments, everyone became less tolerant of pain on average. This change was about the same for everyone—whether people were couch potatoes or avid marathon runners. But active participants still had higher pain tolerance compared to inactive people, despite this reduction. It is unclear why people have become less tolerant of pain over time, but it could be due to aging.
However, we must be careful when interpreting the findings. Assessment of physical activity through self-assessment is tricky business as the participants may be tempted to report they are physically more active than they are in reality. They may also have trouble remembering their physical activities, which can lead to over- and under-reporting.
Participants were also asked only about their physical activity in the past 12 months, leaving the remaining seven years between assessments unaccounted for in the analyses. This means that someone can be classified as sedentary despite engaging in vigorous physical activity for seven out of eight years. Such cases can distort the results and lead to misinterpretation of the results.
Exercise and pain
Given these results, it is interesting to speculate how physical activity may affect pain tolerance. Although we have some ideas as to why this connection exists, we are still far from knowing the full picture.
One of the possible explanations for this connection could be due to some physiological changes that occur after exercise – such as, for example, exercise-induced “hypoalgesia”.. This essentially refers to the reduction in pain and tenderness that people report during and after exercise. A good example of this is runner’s bloat, when the body releases its own opioids, the so-called endorphins. These hormones bind to the same receptors as opioids, producing a similar pain-reducing effect.
However, endorphins are only part of the magic behind runner’s drinking. Research suggests endocannabinoid system it has similar effects after exercise. This system is a vast cellular signaling network, which mainly consists of endocannabinoids and their receptors. These are neurotransmitters produced by the body that are involved in many processes, including the regulation of sleep, appetite and mood.
Research also shows that they can help us tolerate pain better. Studies show that exercise can increase levels endocannabinoidswhich in turn can improve our overall pain tolerance.
But pain is not a purely physiological phenomenon. It is an experience, and as such, is subject to our psychology as much as our physiology.
It could be argued that exercise brings with it a certain level of pain – from stitches and sore muscles to that burning sensation you feel when you’re trying to pull off that last rep.
This is why exercise has the power to change the way we evaluate pain. Exposure to these unpleasant experiences during exercise can help build resilience – our ability to function in the face of stressful eventssuch as bread. Physical activity can also build Self-efficacy – our belief that we can do certain things despite the pain.
Physical activity too improves our moodwhich in turn makes us more resistant to pain. Furthermore, exercise helps us learn how to distract ourselves from pain – eg when we listen to music while running. Regular physical activity can help us overcome fear of pain and movement and allows us to be ready for the experience of pain. Not surprisingly, many of these techniques are used as the basis for pain management techniques.
While there are still many questions that future research will need to answer, this research reminds us how good exercise is for us—even in ways we might not expect. These findings may also add to the growing body of evidence that says exercise can help manage chronic pain.