This week's workout comes from Selena Iaquinta at East Coast Mecca/Powerhouse Gym. This move works your core, as well as your chest.

Start with a set of dumbbells on your back. Make sure the dumbbells are above your chest and shoulders, not your face, straight up in the air, while you lower your legs to work your lower abs. For those with lower back trouble, Selena says to make sure to engage your core muscles, and always start with your legs at the top.

After your leg raises, bend your knees and do a chest press while still on the floor.