It's a proven treatment for depression, but can getting fit really make you happier? Charlotte Sinclair discovers the true power of endorphins

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It’s a truism to say that exercise makes you feel good. But it still bears repeating that there are very few mental or, um, physical stimulants that compare to the sensation of completing a long run or finishing a workout, whether that’s a fifteen minute fast walk or a treadmill burn at Barry’s Bootcamp  (a.k.a hell).  For me, it’s always the end of a session of exercise, when my muscles have given up, and my face is a worrying shade of puce, that I feel the best. Those early minutes in a crossfit class? Awful, horrible, the absolute worst. Those last minutes? Heaven on earth, we’re talking rainbows and unicorns.

Perhaps other, more evolved people feel good during their workout (you know the type: the ones that smile and yell for more when the circuit trainer asks if anyone wants to do another 10 burpees. Sadists.) There’s real, chemical joy to be found in the burn, in feeling your body’s swiftness – all thrum and vigour - and the brain quieting down. But for me it’s all about the finish line and the accompanying swell of good feeling, the serotonin hit of happiness, that giddy endorphin zip.

MORE GLOSS: Charlotte Sinclair on why keeping fit is all in the mind

When marathoners talk about a ‘runner’s high’, the drug analogy is not just hyperbole. Endorphins are neurotransmitters released by the pituitary gland. When we work out, the brain believes we’re under stress; endorphins immediately begin to interact with our opiate receptors, altering our perception of our discomfort or pain. The process is not unlike receiving a shot of morphine, though rather less addictive. These magic brain chemicals not only make you feel better, stronger, more able to cope with the task in hand, but work to enhance our immune system, increase our serotonin stores, and nuke our stress levels. With all these benefits, it’s easy to see why people become self-proclaimed ‘endorphin junkies’.

According to research – with the caveat that all this is variable according to each person’s chemical make up – there are particular forms of exercise that boosts our natural opiate levels. Running, over distance or in short, sharp bursts, appears to act like a reliable endorphin trigger, as does weight training. Psychology has a role to play, too: having a goal in mind often propels the brain to release more endorphins in order to help us meet it, while giving us a peaceful sensation of harmony while we’re at it.

Which is perhaps why so many doctors recommend exercise as a strategy to combat depression. When we exercise intensely, so a German study discovered, endorphins attach themselves to the limbic and prefrontal parts of our brains, the same areas connected to our experience of falling in love, or listening to Mozart. (So that’s why I leave my spinning class grinning like an idiot.) There is also, so research tells us, another chemical at work here when we exercise, something called endocannabinoids, which has been described as, yes, the brain’s version of marijuana.

Even better, all this altered state of consciousness stuff is totally legal AND gives you a smaller bottom! Next time someone complains about exercise being boring, just drop the phrases endorphin opiates and endocannabinoids. That should do it.

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