Neural Adaptations to Resistance Training

Neural adaptations to resistance training are changes in how the nervous system controls muscle activity after repeated exercise against resistance. They can help a person produce more force without a proportionate increase in muscle size. Such changes are thought to be especially important for strength gains during the early weeks of training, although the exact neural processes responsible remain uncertain .¹

Muscles produce force when the nervous system activates motor units, each consisting of a motor neuron and the muscle fibers it controls. Studies have observed training-related changes in the force level at which motor units begin firing and in their firing rates. These findings show that the neural control of muscle force can change with resistance training .¹

Neural adaptations differ from muscle hypertrophy, which is an increase in muscle size. Both may contribute to strength development, but greater strength does not necessarily mean that muscle fibers have grown by a matching amount .¹

Some strength improvements are specific to the practiced movement. Researchers have investigated possible changes at several levels of the nervous system, but the precise sites responsible for the observed motor-unit changes remain uncertain. Neural adaptation therefore describes a set of training-related changes, not one established mechanism .¹