Final answer:
The statement is false, as true synergy refers to muscles working together to produce movement rather than one stopping the action of another. The described scenario is more indicative of antagonistic muscle action.
Step-by-step explanation:
The statement 'True synergy occurs when a muscle contracts to stop the secondary action of another muscle' is false. True synergy refers to muscles working together to produce a coordinated movement. Synergistic muscles can complement each other's actions, but one contracting purely to stop the action of another would be more accurately described as antagonistic action rather than synergy. In typical muscle operation, a muscle contraction usually ends when neural signaling ceases, allowing calcium ions to be pumped back into the sarcoplasmic reticulum and causing tropomyosin to cover the binding sites on actin filaments, which ultimately stops the contraction. Elevated muscle tone can contribute to postural stability and can involve coordinated action of different muscle groups, but it is not an example of true synergy.