If you're looking to tone up your upper body for the Summer, you've got to become friends with the push-up. There are so many variations to isolate certain muscle groups, and make your push-ups more exciting and challenging. Here's another variation to try. You'll need one block or dumbbell for this one.

• Come onto your hands and knees so your hands are shoulder-width distance apart. Elevate your right hand so it is four or six inches off the ground. I like to use a block, but you can also use the edge of a dumbbell.
• Straighten your legs out behind you so your torso is in one straight line. If it's difficult for you to do classical push-ups like this, then rest your knees on the floor.
• Inhale as you bend your elbows out to the sides and lower your chest toward the floor. As you exhale, straighten your arms. If this is too difficult, rest one or both knees on the floor.
• Complete 10 push-ups (or as many as you can) with the right side elevated, then switch sides.