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.
Too much movement in your upper body would result in an ungainly running gait and a lot of wasted energy. To prevent unwanted movement, many of your upper body muscles remain contracted -- this is called an isometric contraction. Isometric contractions result in muscle tension but no actual joint movement.The muscles in your neck must contract isometrically to keep your head up while you run and the muscles of your core or midsection must contract in the same way to stabilize your spine.sometric contractions result in muscle tension but no actual joint movement. The muscles in your neck must contract isometrically to keep your head up while you run and the muscles of your core or midsection must contract in the same way to stabilize your spine.