Apparently this had been studied for a while and is used in rehab. Below are a couple of small, but interesting studies. It looks like this has been repeated at least a couple times outside of the the therapy/rehab setting.
This study tested whether mental training alone could improve physical strength. Through imagining exercise they increased strength in the hip flexor 24%, compared to the group that physically performed the exercise increasing strength by 28%. Both groups somewhat lowered their heart rates and systolic blood pressure.
Through imagining exercise they increased strength in the pinky 35%, compared to the group that physically performed the exercise increasing strength by 53%, they also mentally increased strength of the elbow by 13.5%.
So it seems there is not necessarily a gain in muscle size, but there is a definite gain in strength.
This is interesting, although I am still quite skeptical. Perhaps a physical workout can be enhanced by simply focusing on what you’re doing instead of listening to music or whatever. This might lend to some of the extraordinary strength gains seen by competitive lifters.
Now I’m intrigued to know exactly what imagination regimen these subjects went on to get such impressive results. I’m also curious if this works for anabolic states too, where you would imagine yourself healing in between imagining yourself exercising. Need more info.
I suspected what we are seeing is a neurological improvement not a muscular one. A lot of the initial strength gains people see when the first start lifting is really their nervous system getting more efficient at controlling their muscles. Making more muscle fibers fire at once, support muscles working together to better apply force. I believe imagining doing the exercise improves the brain’s ability to control the associated muscles in much the same way. The muscles themselves are not actually getting stronger.
Aww booo! It’s been a recurring tech fantasy of mine to take a pill or run a current through the brain that stimulates muscle growth without doing exercise. It makes so much more sense than forcing ourselves to tear up muscles just to try and trick it into growing back bigger, skip step B and go straight to C! Though I imagine early testing days would be chaotic.
I don’t know if we’re going to get it into a pill, but I have my suspicions that electrical muscle stimulation will play a part in changing human physique over the next few decades, although to be fair people have thought that since the 70s, so what do I know.
I think @horsfield is on target - neuromuscular efficiency makes a huge difference, and can ramp up much faster than actual muscle size. The visualization exercise are probably impacting the neuro and neuromuscular angles moreso than the actual muscles.
Athletes have been using visualization to great effect for years; downhill racers, divers, they all practice in their head when not “in the field.”