To address the question of the relative importance of the neural input and the mechanical load put on skeletal muscle, we have used a method that separates these two stimuli, so that these can be manipulated separately. For this, we use an in vivo training machine, hereby called a myograph, where the electrical input and the mechanical loading on the muscles is regulated and registered in a highly specific manner. All training sessions is performed with sedated rats, so that no interference with the stimulation pattern or mechanical loading can take place. We then need to set up different strength training regimes that leads to hypertrophy, and compare the relative effect of the different regimes on hypertrophy.