I’ll soon be running, but cursing other runners under my breath!

SPRING is on its way and fair weather, runners across the country will be dusting off their trainers and reluctantly running again.

I say ‘reluctantly’ because many people, myself included, run because they feel they should, not because they enjoy it. And I am jealous of those who get a ‘high’ while doing it.

For years we’ve been told this is caused by endorphins, feel-good chemicals produced by your body that mimic the action of opioid drugs. In fact, while the high is real, it has nothing to do with endorphins, according to a new study from the University Medical Center in Hamburg, Germany.

The researchers took 63 runners who all claimed to experience the ‘high’, and gave them either an injection of naloxone, a drug that blocks the uptake of opioids, or a placebo jab.

After a 45-minute run, most of the runners still reported getting the high, which suggested it wasn’t the endorphins. It turned out it was due to a rise in endocannabinoids, chemicals that mimic the actions of cannabis (and are thought to play a role in mood).

A few years ago I did a similar experiment with Dr Saoirse O’Sullivan, a physiologist from Nottingham University, where we tested three runners and detected a 30 per cent rise in their endocannabinoid levels after exercise.

One, who suffers with depression, told me she self-medicates by running. As Dr O’Sullivan explained: ‘We’re mentally and physically healthier when we exercise, so having a reward system for exercise would seem like a good evolutionary thing.’ But we don’t all get the buzz. Tests show that my endocannabinoid levels don’t rise after exercising. Nonetheless, because I believe in the health benefits, I continue to run, while cursing the happy runners who sprint past me.