workout series: the abominable abdominal Washboard abs are the hottest item in the fitness world and sought after by both men and women. Washboard abs require a lot of discipline, healthy low fat diet and a fairly low percentage of body fat. Many people have an excellent abdominal routine but they also have a thin layer of subcutaneous fat covering up all their hard work. It's important to burn off this layer of fat to see the fruits of your labor.

Working your abs smarter, not longer will help you get in a good workout without doing 250 crunches. For many, the crunch is the only exercise in their abdominal workout and they just keep piling on more sets and reps to reach their fitness goals. If you want to develop your abs, you have to use different exercises just like you would with any other muscle. Try some of the abdominal exercises below to add variety and get a good ab workout.

The Muscles: there are 5 muscles that make up the Abominable Abdominal. The rectus abdominus originates at the pubic bone and attaches to the lower portion of the ribs. Its job is to flex the spine and shorten the distance between the rib cage and the pubic bone. The internal and external oblique muscles (there?s 1 internal and 1 external oblique on each side of the rectus abdominus) are also between the ribs and the pubic bone and they laterally flex the spine (same as above but adding a sideways motion).

Hanging Knee Lift: these can be done from an overhead pull-up bar. This exercise is often done incorrectly, the key is to: use a slow controlled movement, limit upper body movement and not moving you hip joints during the exercise. The abdominal muscles attach to the pelvis not the legs; lifting your knees at the hip joint is a great exercise for your hip flexors but not your abs. Keep your knees and hips stable and lift the pelvis, legs and knees as one unit towards your chest.

The Bicycle: This is a slow, fluid movement that stimulates your abdominal muscle and obliques by crunching and twisting and alternately extending your legs. This may sound a little confusing, but remember that all 4 limbs should be moving at the same time. Lying on your back with your hands behind your head, contract your abs and lift your shoulders off the floor. Slightly twist your torso and point your right elbow towards your left knee as you?re lifting your left knee up until it forms a 45-degree bend (your leg should remain slightly bent). Slowly twist your torso to point your left elbow towards your right knee as you lower your left leg and lift your right knee until it forms a 45-degree angle. Hold the extended leg off the floor until you bring it back to the 45-degree bend. Do as many as you can and go as slow as possible.

Crunch: the crunch can still be a great exercise to include with other abdominal workout. Try variations to the regular crunch to stimulate your muscles differently for better results. Lying on your back, rest your left foot on your right knee and crunch your right elbow towards your left knee. Repeat with the opposite side. Using an exercise ball while crunching is another way to stimulate your abs a little differently and you?ll also use other trunk stabilizing muscles to maintain your balance.

Reverse Crunch: as the name implies, this is performed by crunching the lower portion of the abdominal muscles up towards your chest. Start by lying on your back on the floor with your hands at your sides for balance. You knees should be bent at a 90-degree angle and your upper thighs should be perpendicular to your body. Keep your hip joint and knees in this position throughout the movement. Slowly roll your hips and legs off the floor and flex your lower spine to raise your lower back off the floor. Think about lifting your hips off the floor using your abs and avoid "jerking" into motion and using momentum to complete the exercise. Slow controlled movements will limit risk of injury and give your abs a great workout. This is an advanced exercise and using proper form is important for the effectiveness and to limit injury. Moving your hip joint and knees puts stress to the lower back and should be avoided.

All of these exercises should be done in a slow controlled manner and remember to breath. Going slow helps you avoid building momentum and reduces the risk of injury to your back and spine. If you?re placing your hands behind your head for any abdominal exercises, be careful not to use your arms to lift your head and shoulders. Not only does this place stress on your neck and spine; you?re also removing some of resistance from your abs.