Koaktivierung von Beuger und Strecker - stefaneidelloth/matameko GitHub Wiki
Muscle coactivation occurs when agonist and antagonist (or synergist) muscles surrounding a joint contract simultaneously to provide joint stability.
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In order for muscle coactivation to occur, it must inhibit reciprocal innervation, which occurs when a muscle contracts and the synergist muscle relaxes.
https://en.wikipedia.org/wiki/Muscle_coactivation
During maximal coactivation, the monosynaptic excitatory pathway (Ia) as well as the disynaptic reciprocal inhibitory pathway (Ib) are exposed to spinal inhibition via descending supraspinal pathways. ... The increase in muscle and joint stiffness mainly results from a direct activation from the CNS with the cerebellum playing an important role in switching from reciprocal activation to coactivation
https://www.mitchmedical.us/sports-medicine-3/antagonist-muscle-coactivation.html