Motor unit plasticity is currently incorporated into many professional and collegiate training regiments. Motor unit plasticity can be measured in many ways, the most important of which being neural firing frequency, EMG amplitude, muscle force output, pre-synaptic inhibition, and synchronization. Firing frequency is defined as the number of neuronal signals sent per second on one motoneuron. This frequency is measured in Hertz. Maximum firing frequency in humans typically ranges from 100–200 Hz. Studies incorporating electromyography have proven that adaptation mechanisms occurring as a result of resistance training can drastically increase the maximal firing frequency of a motoneuron. Firing frequency has been shown to
Per-unit system this, the base currents I and I are related in the opposite way that V and V are related, in that formula_31 The reason for this relation is for power conservation S = S The full load copper loss of a transformer in per-unit form is equal to the per-unit value of its resistance: formula_32 formula_33 Therefore, it may be more useful to express the resistance in per-unit form as it also represents the full-load copper loss. As stated above, there are two degrees of freedom within the per unit system that allow the engineer to specify any per unit