https://stream.echo6.co/videos/watch/84c280e1-b6ba-493f-a789-9b7500b286ca Official Ninja Nerd Website: https://ninjanerd.org Ninja Nerds! In this lecture, Professor Zach Murphy presents part 3 of our neuromuscular junction series, focusing on the sliding filament theory of muscle contraction. We begin by connecting the events of excitation-contraction coupling to the mechanical process that generates force within skeletal muscle. The discussion starts with the binding of calcium to troponin C, the resulting movement of tropomyosin away from actin’s myosin-binding sites, and the initiation of cross-bridge formation between actin and myosin filaments. From here, we explore the cross-bridge cycle step-by-step: myosin head attachment to actin, the power stroke driven by ADP and Pi release, detachment following ATP binding, and re-cocking of the myosin head after ATP hydrolysis. We also emphasize how the coordinated shortening of sarcomeres produces overall muscle contraction due to the sliding of thin filaments past thick filaments without changing their individual lengths. We then highlight the role of ATP not only in powering the power stroke but also in enabling muscle relaxation by allowing cross-bridge detachment and fueling calcium reuptake into the sarcoplasmic reticulum. Enjoy the lecture and support us below! 🌐 Official Links Website: https://www.ninjanerd.org Podcast: https://podcast.ninjanerd.org Store: https://merch.ninjanerd.org 📱 Social Media https://www.tiktok.com/@ninjanerdlectures https://www.instagram.com/ninjanerdlectures https://www.facebook.com/ninjanerdlectures https://x.com/ninjanerdsci/ https://www.linkedin.com/company/ninja-nerd/ 💬 Join Our Community Discord: https://discord.gg/3srTG4dngW #ninjanerd #NMJ #Musculoskeletal Sun, 19 Apr 2026 09:20:55 GMT https://validator.w3.org/feed/docs/rss2.html PeerTube - https://stream.echo6.co https://stream.echo6.co/client/assets/images/icons/icon-512x512.png https://stream.echo6.co/videos/watch/84c280e1-b6ba-493f-a789-9b7500b286ca All rights reserved, unless otherwise specified in the terms specified at https://stream.echo6.co/about and potential licenses granted by each content's rightholder.