The placebo effect has long been known to add to the benefit we can get from medication.
It also means that even a fake treatment can have a potent effect, if we believe it will be helpful.
Now a growing body of research suggests there can be a similar effect when it comes to how much we get out of exercise.
In the most recent example, a study by scientists at the University of Agder in Norway showed that simply telling people they were getting a ‘special’ type of training led to greater physical improvements.
In the study, which involved 40 men and women in their 20s, one group was told they were each being put on a specially tailored training regimen; the rest were told they were being put on the same training plan as each other.
The researchers said it may have been that volunteers exercised with greater intensity because they expected the training plan to have the desired effect (file image)
The results, published in April in the journal Scientific Reports, showed that those who believed they were following a tailored training schedule experienced greater increases in muscle size and could do more squats (file image)
In reality, all 40 volunteers followed almost the same regime — involving a mixture of 20 metre sprints, leg-press exercises and squats — over the ten-week experiment.
Yet the results, published in April in the journal Scientific Reports, showed that those who believed they were following a tailored training schedule experienced greater increases in muscle size and could do more squats.
The researchers said it may have been that volunteers exercised with greater intensity because they expected the training plan to have the desired effect.
Alternatively, they may have felt compelled to work hard, to show the regimen produced good results, because it was personally tailored (or so they thought).
But it could also be that the placebo effect didn’t make them work out harder — rather, having a tailored exercise plan reduced their anxiety, which reduced muscle tension and made movements more efficient and fluid.
Kolbjørn Andreas Lindberg, a sport scientist who led the study, said: ‘If you believe the training programme you are following is optimised for you, that will have an effect. It’s exactly the same as the placebo effect in medicine.’
Similar benefits have been found in people who use caffeine — or, think they’re using it — to try to improve their workouts.
Caffeine has been shown in some studies to produce marginal gains in physical performance by helping muscles produce more force.
Muscles need calcium to contract, and caffeine stimulates the release of calcium into muscle tissue, allowing it to contract more often and with greater power.
But the same effects can be achieved by pretending to someone that they have consumed caffeine, according to a 2019 study published in the International Journal of Sports Physiology and Performance.
Researchers at Canterbury Christ Church University asked 11 athletes to run 1km as fast as they could three times.
Before the first two runs, they were given a drink they were told contained caffeine — in fact, the second one did not contain any.
For the third run, they had no drink at all. All 11 participants did indeed run faster after a caffeine drink than after no drink at all. But they ran almost as fast in the second run, when they thought their drink contained caffeine.
Dr Philip Hurst, who was involved in the study and is a senior lecturer in sports and exercise psychiatry, says: ‘If someone thinks they’re having caffeine and that it’s going to help them, then they may try a bit harder.
‘Studies show the placebo effect in sports can improve performance between 1 and 3 per cent. That may not seem a lot but it could be the difference between winning a medal at the Olympic Games and not making the final.’
Non-athletes among us can also benefit. A study by Harvard University in the U.S. found that just changing the way we think about exercise may boost our fitness. They looked at 84 hotel maids who did physically demanding work all day. Yet most of the women did not see themselves as fit.
Researchers showed half the group how they were actually meeting recommended exercise levels just by doing their job, but left the other half thinking they were largely inactive.
A month later, tests showed that the women who’d been told they were exercising had experienced an average 10 per cent drop in blood pressure — while in the rest, there was no change.
The researchers, writing in the journal Psychological Science in 2007, concluded this was because if you believe you are exercising, your body may respond as if it is.
While hiring a personal trainer to set you goals may improve your outcomes, a cheaper way to capitalise on the power of the mind is to exercise with others who you think are fitter than you.
A 2012 study at Kansas State University in the U.S. found that volunteers who did this increased their workout time and intensity by up to 200 per cent, compared with when they trained alone.
Similarly, a 2010 study by Santa Clara University in California showed that people who exercised with very physically fit friends tried harder to be as active as them — but those who exercised with less fit pals became lazier and reduced their efforts, reported the Journal of Social Sciences.
‘The placebo effect is very much a social phenomenon,’ says Dr Hurst. ‘You’re more likely to respond to it when you are around other people.’