Try to do both of these moves as a superset – one after the other – everyday. Aim for 5 supersets, but start with 3. Both exercises have you positioned starting on your back, so you can take zero rest in between. Take a 30 second break between supersets, then repeat the sequence. This is meant to keep your core engaged, for a quick burn.
Scissors (20 reps) – Lie flat on your back, extending one leg straight up and lifting the other leg off the floor a few inches. Flex your feet, and switch position with your legs, holding briefly before switching back to start (1 rep = 2 switches). Keep legs as straight as possible throughout. You can keep your arms down by your sides, or place your hands under your hips. Be sure to keep your lower back on the ground. For more of a challenge, place your hands behind your head and crunch up slightly and hold the crunch as you scissor your legs.
Cross Touch Abs (20 reps) – Laying flat on your back, extend both legs straight up over your hips with your feet separated a couple inches. Crunch up and reach your right hand to touch the outside of your left foot, twisting your torso slightly. Lower and repeat reaching the left hand to the outside of the right foot. (1 rep). When lowering down, keep your shoulders off the ground to maintain a crunch throughout.