When your muscles grow larger through exercise and strength training, it's primarily due to an increase in the size and number of muscle fibers. This process is known as muscle hypertrophy. While the nervous system itself doesn't necessarily grow larger in response to muscle growth, it does undergo adaptations to efficiently control and coordinate the larger muscles.
The nervous system includes the brain, spinal cord, and peripheral nerves. It plays a vital role in sending signals to your muscles to contract and relax. As your muscles grow, your nervous system needs to adjust its signaling to effectively activate these larger muscle fibers. This involves recruiting motor neurons, which are nerve cells that connect to muscle fibers and control their contractions.
Over time, with consistent training, the nervous system becomes more efficient at coordinating muscle contractions. This is why trained athletes can exhibit greater strength and control over their muscles compared to untrained individuals, even if the size of their nervous system hasn't visibly changed.
So, while the nervous system doesn't grow larger like muscles do, it undergoes adaptations to optimize muscle control and function in response to muscle growth and training.