Abs
Back
Exercise Ball
intermediate
strength
duration
Steps : 1.) Start by laying with your forearms placed upon an exercise ball with your fingers interlaced and extending your legs out behind you so that your toes are rested upon the floor. 2.) Keep your body straight out and hold onto this position for as long as possible. 3.) Repeat for as many reps, sets and however long as desired.
Alternative Abs Exercises