Final answer:
The body recruits the lower-threshold motor units first and then the higher-threshold motor units.
Step-by-step explanation:
The statement that the body recruits first the high-threshold motor units and then the lower-threshold motor units is false.
When a muscle needs to generate more strength, it recruits larger motor units with bigger, higher-threshold motor neurons to activate larger muscle fibers. This process is known as recruitment and it results in a progressively stronger muscle contraction as more motor units are activated. Therefore, the body actually recruits the lower-threshold motor units first and then the higher-threshold motor units.