Three group of people were involved in the experiment: one group did nothing, second group was doing actual arm exercises, the third group was just imagenning and visualizing as if they were doing the same arm exercises but in their mind. Few weeks later the arm muscle mass was compared to the original mass at the beginning of the experiment. The first group showed no surprises, the muscle mass remain the same, the second group had predictably increased muscle mass, the third group was a surprise – they gained on average 13.5% of their muscles after the first few weeks and maintained their new muscle mass for three weeks after their “mental exercises” were stopped. It was published in scientific american… The thought alone can actually build muscles…