Rapid regeneration of power stroke in contracting muscle by attachment of second myosin head
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Updated: Aug 9, 2026

Myosin-Specific Adaptations of In vitro Fluorescence Microscopy-Based Motility Assays
Published on: February 4, 2021
1Physiological Laboratory, University of Cambridge, UK.
Abstract:
When Lombardi and colleagues reported the phenomenon of rapid regeneration of the power stroke after a quick release of muscle fibre during a tetanus, they gave an explanation in terms of detachment of cross-bridges and re-attachment further along the thin filament. We show here that the phenomenon can also be explained on assumptions that lead to a majority of myosin molecules being attached by only one head during steady isometric contraction; the other head may then become attached after a quick release and can add its contribution to the early tension recovery after a second release.
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