Endorphins, the body’s own opiate-like chemicals, have long been held responsible for the so-called exercise ‘high’, and experts once thought that we needed to tough it out at a certain intensity, for a given length of time, in order to ‘flick the switch’ and get an endorphin boost. For example, a report in the journal Physician and Sports Medicine concluded that to get an exercise ‘high’, you have to work at 76% of your maximum heart rate, and may need to keep going for two hours or more. But with some exercise fanatics blissing out by doing much less work, and others putting in even greater amounts of effort to no avail, researchers began to realize that the formula wasn’t so simple.
The endorphin fitness ‘myth’
It’s now questionable whether endorphins play much of a part at all in why exercise makes us feel good. This is because there are two endorphin systems in the body – one in the blood circulatory system, and the other in the brain. And although it’s been proven that endorphin levels in the blood increase in response to exercise, those endorphins can’t cross the ‘blood-brain barrier’, so wouldn’t necessarily have much of an effect on mood.
So what is putting that smile on your face when you work out? Researchers now believe that there are a multitude of factors at work – both physiological and psychological.
Going for exercise goals
Simplest of all is the idea that the sense of accomplishment or ‘mastery’ we get from undertaking a challenging workout leaves us aglow. It boosts feelings of self-esteem by demonstrating that we can achieve our goals. But of course, challenge is a personal thing – and it’s important that the level of intensity is pitched just right. If exercise is too easy then we won’t feel we’ve achieved much – whereas if the exercise is too hard we may become stressed and uncomfortable.
In one study, from Kyushu University in Japan, runners who completed ten to 15 minute runs at a self-selected pace – rather than sprinting all-out – successfully enhanced their mood. And backing up the idea that you don’t need to put yourself through a near-death experience to get a ‘high’, Indiana University found that even low-intensity aerobic activity (40% of maximum capacity) could assist anxiety reduction and promote a more positive mood.
Another potential explanation for the workout buzz is the warmth it created in the body, which – like a hot bath – helps muscles to relax and tension to dissipate. But we can’t rule out chemicals entirely. Nor are endorphins the only substances that respond to exercise. For example, exercise can prevent serotonin being taken back up by brain tissue, just like some anti-depressant drugs. It also has an affect on levels of adrenaline and dopamine.
Getting ‘high’ through exercise?
If you’ve yet to experience that magical feeling during or after exercise, make sure that your sessions aren’t too easy or too hard, that you gain a sense of accomplishment from completing them, and that you enjoy the activity.
Bear in mind that getting an exercise ‘high’ may be a question of definition – one person’s ‘pleasantness’ may be another’s ‘total ecstasy’! To prove the point, in a study that asked marathon runners to describe their experience of the runner’s ‘high’, the most frequently picked phrase was ‘general happiness’. There’s no harm in aiming for nirvana!
Whether or not you’ve experienced the famed ‘buzz’ during exercise that makes you feel as if you could go on forever, you will probably agree that exercise can generally boost your mood and energy levels. So get exercising!