2012a-750 adolescent aged agefactors aging biomechanicalphenomena biomechanics child childdevelopment exercise gaitdisorders gynecology humanmechanics infant kinesiology locomotion medical molecularaspects motorabilityinchildren motorskills movementdisorders movementdisordersinoldage neurologic obstetrics olderpeople physicalexertion physiologicalaspects physiology posture posturedisorders