WordNet sense 1 (carry out or practice; as of jobs and professions):

do, practice, practise, do

WordNet sense 2 (put to use):

exert

WordNet sense 3 (the act of using):

employment, usage, use, utilization, utilisation, use

WordNet sense 4 (systematic training by multiple repetitions):

drill, recitation, practice session

WordNet sense 5 (a task performed or problem solved in order to develop skill or understanding):

example

WordNet sense 6 (the activity of exerting your muscles in various ways to keep fit):

workout, exercising, physical exercise, physical exertion

WordNet sense 7 (give a workout to):

work, work out