Instructions
Choose the appropriate dumbbell and set it on the ground near the lower end of a bench.
Lie face down on the bench and position yourself so that your knees are at the edge. Pick up the dumbbell from the floor with your feet, securing it between the arches of your feet. If you have a training partner, have them place the dumbbell in between your feet.
Fully extend your legs, and grab hold on to the side of the bench with your hands for stability.
Bending at the knees only, slowly curl the dumbbell up towards your butt. Raise the dumbbell as far as comfortably possible or just past 90 degrees. Making sure you are keeping your hips on the bench. Lower the dumbbell in a controlled manner back to the starting position. Repeat for desired number of reps.
Tips
You can also perform this exercise on the floor if you do not have access to a bench.