Yes! I can cross train at my desk, while walking my daughter to school, and when doing the dishes. When I leave the slouching behind and lift my ribs, not only am I taller, but I feel my upper abs engage. I call that a double bonus. Are you slouching right now? Try a little desk cross training and sit up straight, with the ribs over the pelvis not behind it, and engage your abs. This should help your aching back too.