A Placebo Can Make You Run Faster?
November 3, 2015 MVP Blog comments
Can a shot of salt water make you a faster runner?
The answer appears to be a resounding yes, if you believe that the salt water contains something that should make you a faster runner, according to a new study of the power of placebos in athletic performance.
Anyone who exercises knows from experience that our minds and mental attitudes affect physical performance. Who hasn’t faced a moment when, tiring at the end of a strenuous workout or race, we are about to quit before suddenly being passed on the path or shown up in the gym by someone we know we should outperform, and somehow we find an extra, unexploited gear and spurt on?
(NYTimes.com, by Gretchen Reynolds)
This phenomenon is familiar to physiologists, many of whom believe that our brains, in order to protect our bodies, send out signals telling those bodies to quit before every single resource in our muscles and other tissues is exhausted. We think we are at the outer limits of our endurance or strength, when, in reality, we may still have a physical reserve available to us, if we can find a way to tap it.
Past studies have shown that lying to people is one way to exploit that reserve. Telling athletes that they are moving slower than in fact they are, for instance, often results in their speeding up past the pace that they thought they could maintain. Or give them a sugar pill that they think contains caffeine or steroids and they will run more swiftly or lift more weight than before.
But none of these studies tested the effects of placebos and deception in relatively real-world competitive situations, which have their own effects on mental responses. People are almost always faster during competitive races than in training, studies show, even when they are trying to replicate race pace.
So, in competition, most people might already be using that last reserve of physical capability. Or there might still be physiological wiggle room.
To find out, researchers at the University of Glasgow recruited 15 male recreational runners for a test of what the volunteers were told was a legal form of erythropoietin, or E.P.O., a substance that increases the number of red blood cells in the body. In many sports, E.P.O. has been used for doping, because more red blood cells means more oxygen is carried to laboring muscles and endurance performance improves.
But the runners were assured that this was a formulation of E.P.O. that was legal for use in research and would have few harmful side effects, since the dosage would be low.
On the other hand, the runners were told, the drug should improve athletic performance since it would increase red blood cells.
The “drug,” however, was saline, which would be given by injection, since past research had shown that the placebo effect tends to be stronger when a substance is injected instead of swallowed.
Before starting the “drug” regimen, though, the volunteers competed in a 3-kilometer track race to determine their baseline finishing times.
Then some of the men continued their normal training for a week, while others received injections of the “drug.”
They all raced again.
Finally, for another week, the men switched, with those who had not received the shot before getting the injections now, and vice versa.
Then they all ran a final three-kilometer race.
Throughout, the scientists collected data about how the men felt physically and psychologically during their workouts and the races.
As it turned out, almost all of them felt that the “drug” had had real and substantial effects. The runners told the scientists that during the week when they were receiving the injections, their workouts felt easier and they were more motivated to push themselves. One man told the scientists, according to the new study, that he had noticed in the gym “that I was doing a lot more in my sets than normal, and also running, I did feel less tired.”
Most of the runners also reported that they recovered better when receiving the injections.
Most important, they almost all significantly improved their three-kilometer race times by about 1.5 percent after taking the “drug,” compared with their times at the start of the experiment.
The runners did not show much if any change in their race times after the control week.
In essence, the fake drug had had a “meaningful performance enhancing effect,” said Ramzy Ross, a physiologist now at the Emirates Advanced Investments Group, who led the study.
Of course, this was a small, short-term study of male runners. But it seems plausible that the effects would apply likewise in other sports and to other genders.
There is, however, a substantial and obvious barrier to the rest of us benefiting from these results. We can’t lie to ourselves about that saline shot or sugar pill. If we plan to give ourselves the placebo, we know what it is.
Still, some evidence exists from medical studies, Dr. Ross said, “that even while knowing a placebo is being taken, the desired effect can happen, so there may be some sort of unconscious psychology going on.”
In that case, a shot of saline, even if you know what it is, might have, he said, a “marginal but still potentially meaningful” effect on how fast you run.