Sit-ups have long been a staple of ab workouts, but research has shown that they can actually do greater damage than good for your body. The newest craze for getting chiseled abs and a stronger core is plank exercises. Much like the sit-up, planks can be completed from the comfort of your home gym and just a few minutes per day will give you significant results. Planks are better for burning off fat with less risk of injury and they offer the bonus of strengthening your lower back.

Standard Plank

Get into a standard push-up position. Your feet should extend straight behind you and your hands should be shoulder-width apart. Place your body weight on your toes and your elbows, forming a 90-degree angle at the elbow and shoulder. Keep your body in a straight line from your head to your heels. Hold this position for as long as you can, with a goal of two-minutes. The longer you hold, the harder the workout, but you can challenge yourself more with variations on the standard plank.

Plank with Leg Lifts

Holding yourself in the standard plank position, lift one of your feet above the other. Don’t lose your stability; holding your hips in place is the key to building core strength in this exercise. Tap the back of one heel with the toes on the other foot. Place the foot back on the ground and repeat the motion for your other leg. Complete five repetitions on each side for one set.

Plank with Arm Lifts

Start in the standard plank position again. Lift one arm straight out ahead of you. Hold for five seconds and switch arms. To make this exercise even more challenging, combine it with the leg lift variation described above. When lifting your arm, lift the opposite leg. Again, maintaining your stability is essential to benefit from this exercise.

Plank with Exercise Ball

There are a couple ways to destabilize your plank for an even tougher workout. Using an exercise ball offers a good variation. Place a small exercise ball under your shins, keeping your back straight. Lift your hips into the air, rolling the ball towards your head with straight legs and back. Once your hips are above your shoulders, lower them back to their starting position. Repeat for 5-7 repetitions.