First things first: Let’s talk about the workout. Kohn gave me a two-round bodyweight circuit with six abs moves. Why bodyweight? Kohn says those kinds of moves have had the most impact on her body.

It’s an effective warm-up exercise to try near the beginning of your workouts or abs circuit. You might prefer to find an ...

I Did A 12-Minute Abs Circuit Every Day' Try This 20-Min Lower Body HIIT Workout Try This 20-Minute HIIT Upper Body Workout Try This 20-Minute Upper Body HIIT Workout Try This 20-Minute HIIT Total ...