Mind Over Muscle: The Surprising Power of Exercise’s Placebo Effect

Summary: If a person believes that an exercise program has been optimized and created specifically for them, the diet will have a positive effect, regardless of the content of the program. Researchers say the placebo effect has health benefits when it comes to exercise.

Source: University of Agder

You can get a better effect from your training if you believe that the training program you are following was designed especially for you, according to Kolbjørn Andreas Lindberg, a researcher at the University of Agder in Norway.

“If you believe that the training program you are following has been optimized for you, that in itself will have an effect, regardless of the content of the program. It’s exactly the same as the placebo effect we know from medicine,” says Lindberg who conducted a pilot study on the effect this can have on training.

The results were published in the journal Scientific reports.

Have you ever taken paracetamol to relieve a severe headache, to feel better before the pill has even had time to work? So you’ve experienced the placebo effect.

Placebo is the name of the somewhat strange phenomenon that occurs when drugs or treatments work better if you think they will.

“The placebo effect has been studied for over 70 years, but examining it in the context of exercise research is new,” says Lindberg.

Placebo drugs are an important part of clinical research. In so-called blinded trials, the active drug and the placebo are given to patients according to a code, so that neither the researchers nor the subjects know who received what.

This way, researchers can objectively assess the effect of the drug.

Forty people participated in the study by Lindberg and his colleagues. After a series of physical laboratory tests, they all received different training programs.

Half of the participants were informed that the training program they had received had been specially adapted to them based on the tests carried out. It was the intervention group.

The other half, the control group, received no such message.

The participants were all given training programs that varied by weight and number of reps, but on average the programs for the two groups were similar.

After completing the eight to ten weeks of training, the participants were again tested in the laboratory.

“It turned out that those who thought they had received an individually tailored training program performed better on average than the control group. Even if the two groups had followed the same program on average,” says Lindberg.

The researchers found differences between the two groups, particularly with squat exercise and general muscle thickness.

It shows a woman exercising
This can be a problem when new training approaches seem to deliver good results. Image is in public domain

“It may be a little surprising that the placebo also applies to exercise. But when you think about it, it makes sense,” says Lindberg.

“There were indications that participants who thought of following a personal program were training a little more and with a higher intensity. Many of these small factors can affect the outcome.

He also thinks the test itself may have had an impact on the outcome: the intervention group may have felt they had to perform since the program was supposed to give them results.

“The placebo effect is widely overlooked when researching exercise results. It can be difficult to conduct a blinded study when comparing training twice a week with training four times a week” , he said.

This can be a problem when new training approaches seem to deliver good results.

“There are good reasons to be skeptical of the fancy new training approaches that are being hyped. Especially considering that virtually no such studies have been controlled for the placebo effect,” says Lindberg.

About this exercise and current psychology research

Author: Press office
Source: University of Agder
Contact: Press service – University of Agder
Picture: Image is in public domain

Original research: Free access.
“The effects of being told you are in the intervention group on training outcomes: a pilot study” by Kolbjørn Lindberg et al. Scientific reports


The Effects of Being Told You Are in the Intervention Group on Training Outcomes: A Pilot Study

Little is known about placebo effects when comparing training interventions. Therefore, we investigated whether subjects who were told they were in the intervention group achieved better training outcomes compared to subjects who were told they were in a control group. Forty athletes (male: n = 31, female: n = 9) underwent a 10-week training intervention (age: 22 ± 4 years, height: 183 ± 10 cm, and body mass: 84 ± 15 kg).

After randomisation, participants were told either that the training program they followed was individualized based on their strength-velocity profile (placebo) or that they were part of the control group (control). However, both groups were doing the same workouts.

Measurements included countermovement jump (CMJ), 20 m sprint, maximum repetition (1RM) back squat, leg press test, muscle thickness ultrasound (m. rectus femoris) and a questionnaire (Stanford Expectations of Treatment Scale) (Younger et al. in Clin Trials 9(6):767–776, 2012).

Placebo increased 1RM squat more than control (5.7 ± 6.4% vs. 0.9 ± 6.9%, (0.26 vs. 0.02 effect size), Bayes factor: 5, 1 (LFten), p = 0.025). Placebo had slightly better compliance than control (82 ± 18% vs. 72 ± 13%, BFten: 2.0, p=0.08).

Importantly, the difference in the 1RM squat was significant after controlling for grip (p=0.013). No significant difference was observed in the other measures.

The results suggest that the placebo effect may be significant in sports and physical training interventions. Ineffective training interventions may not be questioned in the absence of placebo-controlled trials.

Leave a Comment