You can build strength without building muscle mass. In fact, neuromuscular adaptations occur within the first few weeks of a resistance-training program and increase muscular strength without enhancing muscle mass. However, optimal strength improvements occur when you build muscle with weightlifting. Understanding how neuromuscular control affects strength enables you to make informed fitness decisions.
Neuromuscular Control Defined
Neuromuscular control represents communication between your brain and muscles. The functional unit of the neuromuscular system, known as a motor unit, comprises a motor neuron located in your brain and the various muscle fibers it controls. If your brain signals a specific motor neuron, all fibers connected to that neuron activate, or move. Your speed and magnitude of motor-unit activation depends on the activity being performed and the strength of your neuromuscular system. Keep in mind, a trained individual can contract more muscle fibers at any given time than an untrained individual.
Improved Rate of Activation
Within weeks of training, weightlifting expedites how quickly your brain can activate motor units. In response, you become stronger without building muscle mass. Instead, your brain utilizes your current muscle mass more efficiently. For instance, motor units require repeated signals for continuous muscle movement. A fast rate of activation ensures strength remains adequate throughout a given motion.
Enhanced Motor-Unit Synchronization
Your potential for strength increases when motor-unit activation is synchronized, or your brain can signal various motor units at the exact same time. For example, numerous motor units control the muscle fibers in your arm. Activating those motor units simultaneously streamlines muscle movement and enhances force production. Imagine a game of tug of war -- your side will be stronger if all team members pull at the same moment. Strength training enhances motor-unit synchronization and boosts your strength without enhancing muscle size.
Recruiting Type II Fibers
Each muscle contains varying amounts of type I and type II fibers. While type I fibers support endurance-based actions such as standing, type II fibers perform short-term actions requiring greater muscular strength such as lifting a heavy box. Weight training augments your ability to activate type II fibers during physical activity. Once again, this type of neuromuscular change builds the strength of your existing muscle mass without requiring muscle growth, or hypertrophy. Therefore, you may experience greater strength during a weightlifting program without seeing additional muscle mass. As always, consult a doctor before beginning an exercise program.
References
- "National Strength and Conditioning Association's Essentials of Personal Training"; Roger W. Earle and Thomas R. Baechle; 2003
- "ACSM's Resources for the Personal Trainer"; American College of Sports Medicine; 2007
Member Comments