Endorphins: More Than a Feeling?

Posted by Filed Under: Health & Fitness, Science and Research

I don’t get high. It seems that ever since I stepped onto the running scene, I’ve heard accounts of the euphoric place running can take some of its practitioners. But so far, my jaunts have not once taken me to this seemingly mythical runner’s Shangri-La. There’s no doubt running keeps me happy; but, that’s more about my general quality of life, health and contentment. I don’t attribute this to a situational runner’s high.

Am I not training “right”? Maybe I’m just not running hard enough. Occasionally, I feel a bit cheated by this. But, it’s not a big deal. It’s certainly not my motivation to run. If that were the case, I would have stopped a long time ago.

However, a study published recently online in the American Journal of Physiology’s Heart and Circulatory Physiology has got me thinking again about this phenomenon. It seems that not only can endorphins and other opioids released during exercise lead to the runner’s high, but they might also be prime players in the mechanism that keeps our hearts healthy.


While delving further into the questions of why and how exercise benefits the heart, a team at the University of Iowa looked to see whether the opioids released during exercise might be involved in the cardio-protective effects of exercise in rats. In the study, they compared exercised with non-exercised rats and found that exercised rats experienced less heart damage from a heart attack than the non-exercised rats. When they then injected rats with a chemical to block their opioid receptors, the exercised rats lost all the heart-healthy benefits of exercise.

Additionally, the team noted an association between exercise and a rise in opioid system gene expression in the heart, and also a change in the expression of genes which are involved in inflammation and cell death.

The rat results suggest that the endorphins and other opioids that are released when we exercise may be involved in the body’s mechanism for keeping our heart’s healthy. If this proves to be the case, I’m hoping that, runner’s high or not, my body is releasing these chemicals when I am exercising hard, and they are working their magic to protect my heart. I’d be happy knowing my heart was reaping the benefits, even if I don’t necessarily feel like I am walking on air.

About Nora

I am a native Californian currently settled and running my way bit by bit around the South East of England. Besides running, my training activities include biking, hiking, swimming, yoga, and tap dancing in place while in line at the grocery store. I am addicted to photography and run most races with my camera in hand, just in case.

  1. Huw on December 19th at 9:58 am

    Hi there, great article. In my experience a) some highs are a lot higher than others, so you barely notice the low highs b) you can’t guarantee that a certain session will produce a high – sometimes a set of sprints, sometimes a threshold run, sometimes a long run – it can be an elusive beast. This leads me to think that, like gene expression itself, and indeed fitness adaptations, a high is best left to random generation: it won’t respond quite as well to a rigidly imposed system as it will to a ‘how you feel’ approach to running and resting.

  2. Visualizing the High | Triathlon Daily on March 19th at 6:09 am

    […] Despite an air of mystery surrounding the phenomenon, others still cross their fingers and hold out hope that they might eventually feel it. Now researchers are starting to obtain results that might one day earn this seemingly mythical […]