muscle-building exercises (or a system of musclebuilding exercises) involving muscular contractions against resistance without movement (the muscles contracts but the length of the muscle does not change)
of a crystal system characterized by three equal axes at right angles
the activity of exerting your muscles in various ways to keep fit
put to use
the act of using
do physical exercise
systematic training by multiple repetitions
a task performed or problem solved in order to develop skill or understanding
