There's little question that triathletes, especially those who dabble in the Ironman, are tough. The race itself is hard enough, but the hours of daily punishment required for peak training are hard to fathom. A new study now offers important insights into why some folks might repeatedly compete in these grueling events: Triathletes, it turns out, feel less pain and have less fear of pain than people who are averagely active. The results support the idea of an inherent range of tolerance to pain that might predispose some to engaging in intense exercise. More intriguingly, the data imply that hard workouts themselves could lead to better handling of pain.
"The study suggests there is this possibility that by training your body by exercising vigorously, you might be able to influence how your body can regulate pain," said Jamie Rhudy, a psychologist at the University of Tulsa who was not involved with the research but wrote an accompanying commentary in the journal 'Pain.'
For the study, researchers from Tel Aviv University put 19 triathletes and 17 casual exercisers through the wince-inducing tests of heating or dunking an arm in cold water. Participants also filled out questionnaires assessing their feelings about pain in given situations. Overall, the triathletes reported feeling less pain and being less concerned about experiencing it than those who merely jogged, swam or took aerobics classes.
A key mechanism thought to underlie the general perception of pain is a sort of built-in bodily pharmacy that dispenses natural opioids – the same chemicals found in painkilling drugs like morphine. Exercising releases these opioids, triggering pain relief and euphoria; a common example of the phenomenon is "runner's high." These opioids act upon neural circuitry descending from our brain into the spinal cord that can diminish or enhance sensation. "We know from animal and, to some degree, human studies that we have neural circuits that allow our body to regulate pain," Rhudy said.
The big question now, in light of the study, is whether some of us are born with good pain inhibition systems – and are thus likelier to end up in an Ironman – or if the system can be modified by the act of exercise itself. Further research to answer this question is in the works, and the answers will be important, for example, with helping people deal with chronic pain, such as fibromyalgia. Rhudy said that one of the best treatments for the condition is, in fact, exercise. "Chronic pain is an awful catch-22 situation," Rhudy said. "When you're in pain all the time, that means you're going to be less likely to exercise, and by not exercising that puts you at risk for not being able to engage this pain inhibition circuit more readily." It could very well be that, in a vicious cycle, a lack of exercise even serves to promote pain perception by taking inherent pain-dulling services offline.
Regardless of whether the ability to take the pain is ingrained or acquired, the research says that getting some exercise can't hurt, so to speak.