You don't have to work yourself into the ground to get tight abdominal muscles because the best abdominal exercises are really not that difficult to do. The important think to remember is not to strain your back. If you are working out on the floor make sure you are on a level surface and have a comfortable exercise mat.
A study at the Biomechanics Lab at San Diego State University looked at a variety of common abdominal exercises in order to determine what really works. The study compared 13 abdominal exercises, ranging from the traditional crunch to more complicated activities, using at-home and gym equipment. Here are the best tried and tested abdominal work outs to get those muscles tight and trim.
The Bicycle Manoeuvre
Lie flat on the floor with your lower back pressed to the ground. Place your hands palms down, each side of your head. Bring your knees up to a 45-degree angle and slowly go through a bicycle pedal motion. Each time you cycle, touch your left elbow to your right knee, then your right elbow to your left knee. Remember to breathe evenly throughout the exercise.
Exercise Ball Crunch
Sit on the exercise ball with your feet flat on the floor. Let the ball roll back slowly and lie back until your thighs and torso are parallel with the floor. Contract your abdominal's raising your torso to no more than 45 degrees. To work the oblique muscles, make the exercise less stable by moving your feet closer together.
The Vertical Crunch
Lie flat on the floor with your lower back pressed to the ground. Put your hands behind your head for support. Extend your legs straight up in the air, crossed at the ankles with a slight bend in the knee. Contract your abdominal muscles by lifting your torso toward your knees. Make sure to keep your chin off your chest with each contraction. Exhale as you contract upward; inhale as you return to the starting position.
Long Arm Crunch
Lie on your back with your knees bent and feet flat on the floor. Extend your arms overhead. Slowly raise your arms, head, shoulders, and upper back about 30 degrees off the floor. Hold, and then slowly lower. Keep your arms straight, by your ears, and in line with your head. Do not throw them forward to help you.
Lie on the floor with your arms at your sides, feet off the floor, and hips and knees bent at 90-degree angles. Slowly contract your abs, and press your back into the floor, tilting your pelvis and lifting your hips 2 to 4 inches off the floor. Keep your upper body relaxed. Hold, and then slowly lower.
Lie on your belly, keeping your hips and pelvis flat. With your hands under your chin, contract your lower back muscles, and lift your chest about 30 degrees, or 3 to 5 inches off the floor. Hold, and then slowly lower. (For an easier version, rest your arms by your sides, palms facing up. For a more challenging version, extend your arms straight overhead.)