wicked-naughtily or annoyingly playful; teasing and worrying with impish laughter; a wicked prank. impish, implike, mischievous, pixilated, prankish, puckish, arch. playful-full of fun and high spirits; playful children just let loose from school.
Inspiratory Muscles. The principal muscle of inspiration is the diaphragm, a domed sheet of muscle that separates the thoracic and abdominal cavities. The diaphragm attaches to the lower ribs, as well as to the lumbar vertebrae of the spine.
Antagonist and agonist muscles often occur in pairs, called antagonistic pairs. As one muscle contracts, the other relaxes. An example of an antagonisic pair is the biceps and triceps; to contract-the triceps relaxes while the biceps contracts to lift the arm.ecause a flexor muscle is always a flexor, in flexion it is the agonist, and in extension it is the antagonist. Conversely, an extensor muscle is the agonist in extension and the antagonist in flexion.