Muscle contraction: Sliding filament history, sarcomere dynamics and the two Huxleys.

Despite having all the evidence needed to come to the right conclusions in the middle of the 1800s, it was not until the 1950s that it was realised by two unrelated Huxleys and their collaborators that striated muscle sarcomeres contain overlapping sets of filaments which do not change much in length and which slide past each other when the muscle sarcomere shortens. It then took quite a while to convince others that this was the case, but now the idea of sliding filaments is fundamental to our understanding of how any muscle works. Here a brief overview of the history of the discovery of sliding filaments and the factors that were missed in the 1800s is followed by an analysis of the more recent experiments which have added to the conviction that all muscles operate on the same guiding principles; two sets of sliding filaments, independent force generators and a mechanism of protein rowing that makes the filaments slide.