The quality of thought is also reported to be calm and restful in nature. The EEG of non-relaxed individuals shows relatively low voltage high frequency brain activity that is not synchronized. When deeply relaxed, the dominant frequency of brain nerve firings slows, portions of the brain appear to fire in a synchronized fashion, and a high voltage slow frequency pattern can be recorded. We refer to this EEG pattern as alpha activity. Everyone produces some alpha activity prior to falling asleep.
Difficulty producing alpha activity is associated with sleep onset insomnia.
First, relaxed people are very still. If they move at all, they do so slowly and gently. Second, muscle tone is greatly diminished when people relax. Muscle tone is the background level of muscle tightness in between overt muscle movements. Many of us get sore, aching muscles in our lower backs and shoulders or develop muscle tension headaches when muscle tone is too high for too long.