Effect of performance-enhancing drugs is due to placebo effect

Performance-enhancing drugs can improve a runner's best time even when they haven't taken them, thanks to the placebo effect which increases the athletes' potential motivation, according to a new study.
The study published in the journal Medicine and Science in Sports and Exercise lends support to the idea that the power of the mind affects physical performance.
The study examining the placebo effect, response to a placebo, found that endurance runners who thought they were injecting a fictional performance-boosting drug called OxyRBX improved their race time even though they had taken only saline.
Investigators from the University of Glasgow told 15 endurance-trained club-level runners that they were being given a new performance-enhancing drug called OxyRBX which was said to improve oxygen delivery to the muscles in a similar way to a hormone called recombinant human erythropoietin (r-HuEPO).

The runners, who all had personal best times over 10 kilometres of 39.3 minutes on average, self-injected the saline placebo, thinking it to be OxyRBX, over seven days and 3 kilometre running performance was assessed.
The runners improved their race time by an average of 1.2 per cent - a small but significant margin after taking the placebo.

Participants reported reductions in physical effort, increased potential motivation and improved recovery after running following the saline injections.
"The change in performance was of clear sporting relevance, albeit smaller than the improvement that would be produced by r-HuEPO," said Jason Gill of the University of Glasgow.

"The placebo may work by reducing perception of effort and increasing potential motivation in line with a psychological expectation of performance," he said.
A placebo is anything that seems to be a real medical treatment, but isn't. It could be a pill, a shot or some other type of fake treatment.