Adjective
myofibrillar (not comparable)
(anatomy) Of or pertaining to myofibrils.
However, as muscles become adapted to the exercises, soreness tends to decrease. citation Weight training aims to build muscle by prompting two different types of hypertrophy : sarcoplasmic hypertrophy and myofibrillar hypertrophy. Source: Internet
I.e, a bodybuilder will use sarcoplasmic hypertrophy most of the time, but may change to myofibrillar hypertrophy temporarily in order to move past a plateau. Source: Internet
Sarcoplasmic hypertrophy leads to larger muscles and so is favored by bodybuilders more than myofibrillar hypertrophy which builds athletic strength. Source: Internet
Similarly, solutions of salt and sodium phosphates can be injected to soften and swell the myofibrillar proteins. Source: Internet