The authors examined how the stability of the current total isometric force (F_T) produced by four fingers is influenced by previous and expected voluntary changes in F_T. The authors employed the synergy index obtained from the across-trial uncontrolled manifold analysis to quantify the stability of F_T. The authors compared two tasks with similar histories of F_T changes; one in which participants expected changes in F_T in the future, and one in which they expected no changes in F_T. The stability of F_T was lower in the former task, indicating the existence of a novel type of anticipatory synergy adjustment. Disparate histories of F_T changes yield inconsistent changes in stability, driven by individual differences in the covariation in the finger forces that leave F_T invariant. Future research should focus on exploring these individual differences to better understand how previous and expected behavior changes influence the stability of the current motor behavior.