Myoclonus is a rapid, irregular and inconsistent involuntary contraction of the muscles of the limbs or trunk, which can be classified as pathological or physiological.
Bedtime muscle twitches are actually a form of physiological myoclonus and can occur in people of all ages, mostly during non-rapid eye movement sleep.
This type of myoclonus usually has mild symptoms, rarely interferes with life, and generally requires no treatment.