Strength training can also help with other neural factors, including the co-activation of agonist and antagonist muscles. This co-activation can result in improved efficiency of both groups that contract and relax in an organized manner during movement (WILLMORE; COSTILL, 1999).
In a year, when the agonist muscle receives the impulse to contraction relaxes its antagonist through inhibition. For an agonist muscle to produce maximum strength, all muscle motor units must be recruited to minimize the intensity of co-activation, thus causing its maximum contraction.
So, the co-activation decreases the force produced in the desired direction. It is suggested that strength training leads to an increase in the inhibition of the antagonists (Hakkinen, 1994; Enoka, 1997). The reduction in co-activation explains part of the strength gains attributed to neural factors.
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