Synonyms for Athletic (same or very similar meaning)
WordNet sense 1 (having a robust muscular body-build characterized by predominance of structures (bone and muscle and connective tissue) developed from the embryonic mesodermal layer):
muscular, mesomorphicWordNet sense 2 (vigorously active):
acrobatic, gymnasticWordNet sense 3 (characterized by energetic activity):
activeFrom the ODE community, based on WordNetadd/edit