My favorite abs workout. I try to do it a minimum 2-3 time a week 1 day yes one day no, and always before boxing training. I warm up with some cardio first, Either jump rope or a 1-3 mile run. Four sets of each exercise. If your a beginner start with reps of 10 and work your way up to 4 sets of 25 of everything. Should take about 30 minutes till done. It’s like almost like running 3 miles on your abs instead of with your legs. Depending on your diet and exercise habits you see a stronger looking core in 2-3 three weeks, even a smaller looking waist. Enjoy, it’s really good routine.