Research: the muscle power of positive thoughts

Positive thinking and training your muscles? It’s possible, and it all has to do with the way our muscles are controlled. In the article on muscle memory, I discussed the connection between the brain and the muscles. By performing actions such as writing and cycling, you send signals from your brain to your muscles. The more often you send these signals, the stronger the connection between the muscle and the brain becomes.

This type of “muscle memory” ensures that practice makes perfect. But what happens if you send the signals without actually performing the action? For example, if you imagine yourself cycling and perform all the associated actions while thinking positively. Does the connection also strengthen, allowing you to benefit from it when you actually start cycling? Yes, it seems so in the studies discussed in this article.

Positive thinking about exercise during rest between sets

Researchers from the University of Lyon had 21 students who had no previous experience with strength training train three times a week for four weeks.

They had them perform leg press and chest press exercises. They asked the test group (referred to as the MI group in the study, “motor imagery”) to visualize performing the exercises during the rest periods between sets. The control group (CTRL) engaged in neutral activities. After three weeks, the difference in the increase in maximum strength, number of repetitions, and muscle size between the two groups was examined. Particularly, the increase in strength in the leg press showed a significant difference.

The MI group was instructed to visualize and feel the correspondent contractions during the rest period, whereas the CTRL group carried out a neutral task. The maximal voluntary contraction (MVC) and the maximal number of repetitions (MR) using 80% of the pre-test MVC weight were measured. Although both MI and CTRL groups enhanced their strength through the training sessions, the leg press MVC was significantly higher in the MI group than in the CTRL group (p<0.05)

The graph below shows the difference in results in maximum strength on the leg press and chest press between the control group (white) and the test group (black). Especially on the leg press, you can see a clear difference in strength and endurance (number of reps). The growth in leg size was also greater in the group that visualized the exercise in between. The differences on the arms and chest (the chest press) were smaller.

So, it may have added value to visualize the execution of the next set in silence rather than chatting between sets.

“Try to imagine yourself performing the motor sequence with your eyes closed, by perceiving the different movements just as if you had a camera on your head, and feel the body’s sensations“, was the instruction from the researchers. “You have to see and feel yourself in your own body.”

Visualizing a bicep curl without training the bicep

One study went a step further. It showed that muscle growth can even occur when only visualizing training a muscle. Researchers from the Cleveland Clinic Foundation had one group of subjects perform exercises to train their little finger muscles, while another group only imagined doing the exercises. After twelve weeks, both groups showed an increase in finger strength and muscle size, although the growth in the group that actually trained the finger muscles was greater.

This means that your thoughts, feelings, and intentions also influence muscle growth. Just thinking about it isn’t enough for optimal growth, but it does play a role. But how can this be explained?

Brain exercises

One explanation is that by visualizing a movement, you activate the same motor areas in the brain as when you actually perform the movement. But the muscle is not trained, so why would it grow?

Because not only the muscle cells adapt to training, but also the nerve cells. These nerve cells are better able to control the muscles involved in the movement. And that may be the basis for muscle growth through visualization.

This is also why mental training is used in rehabilitation. If, for example, a shoulder muscle is injured, it cannot be trained properly due to the pain. But by visualizing training, the brain continues to send signals to the muscle. This keeps the muscle connected to the brain, which accelerates recovery. This is also called “mental practice”.

Conclusion

It’s clear that positive thinking, or rather visualization, can help in muscle growth. It’s not a substitute for physical exercise, but it can complement it. This makes it an interesting tool for athletes who want to optimize their training. And it’s not only useful for athletes, but also for people who, for example, are injured or bedridden for a long time.

So next time you’re waiting for the bus, imagine yourself lifting weights. Who knows, maybe it will make you stronger.

References

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