Q: Mike, I have read in a couple of your responses that abs get exercised from doing other core exercises. Does this suggest that we should be clenching our ab muscles as we lift?

A: You don't need to clench ab muscles any more than necessary to maintain good form, but good form for many exercises (especially deadlifts, squats, and lunges) requires that you tense both your abdominals and lower back muscles to stabilize your body and provide a strong support base for the exercise. It is quite common, for example, for new trainees to get muscle soreness in the abdominal region after doing squats which indicates a degree of abdominal involvement.

This involvement of abdominal muscles should happen quite naturally, but if you totally do not feel that you are tensing your abdominals and/or lower back muscles during the squat, for example, you should consciously work on that until you get the feel for the proper form.