As you know, I like to mix up my workouts. I recently came across Amanda Lee . Who is Amanda Lee, you ask? Well, she is Kourtney Kardashian 's in-house Poosh fitness expert. Amanda is sharing five simple moves below to add to your at-home exercise list. If you’re looking to strengthen your abs without doing a single sit-up, this one’s for you. Learn each 30-second motion that will tighten + define your core. 30 Second Moves For Stronger Abs Whether you prefer to perform each