A thicker muscle cell means we're essentially producing a larger force. So when we exercise often we increase the thickness of the individual myofibus down inside each muscle cell by increasing the number of actin and myosin in those myofibus. This in turn increases our thickness, our diameter of that muscle cell. A muscle cell with a larger thickness, a larger diameter will exert a greater force than one with a smaller one. So this basically concludes our discussion on the motor unit. So the motor unit is nothing more than the motor neuron as well as all the muscle cells that that particular motor neuron actually controls.