Before revision:  We derive the force-length loop under varying stimulation by splicing Lissajous loops obtained under constant stimulation . This splicing approach captures the force-length loop shapes in muscle that are not seen in non-tunable materials, and yields a nondimensional parametrization for the space of possible responses of tunable materials .
After revision:  We derive the force-length curves obtained under periodic length oscillations. But unlike fixed-stimulus measurements, work loops exhibit unusual but functionally critical features like work-producing loop reversals and self-intersections. We tested the hypothesis that work loops emerge by splicing the rheological responses obtained under fixed stimulation and found that it accurately predicts the loops in experimental data on sculpin skeletal muscle and in numerical sarcomere simulations. Thus, classical rheological loops and splicing underlie the emergent shape of muscle work loops under steady dynamical conditions .