A reverse stroke characterizes the force generation of cardiac myofilaments, leading to an understanding of heart function. Yongtae Hwang, Takumi Washio, Toshiaki Hisada, Hideo Higuchi, Motoshi Kaya Proceedings of the National Academy of Sciences Jun 2021, 118 (23) e2011659118; DOI: 10.1073/pnas.2011659118