A major effect of long-term weightlessness involves the loss of bone and muscle mass. Without the effects of gravity, skeletal muscle is no longer required to maintain posture and the muscle groups used in moving around in a weightless environment differ from those required in terrestrial locomotion.
Marina /ma-ri-na/ [3 sylls.] as a girls' name is pronounced mah-REE-nah. It is of Latin origin, and the meaning of Marina is from the sea. From marine. A saint's name. Shakespeare gave the name to Pericles' daughter in his play Pericles, Prince of Tyre.
It is believed that the name derives from the Latin 'marinas' meaning dark haired or more likely of dark appearance, and it is probable that the word was applied as a less than friendly nickname to the Moorish Invaders of Spain who conquered the country in the t century.