Flat tummy with these best Abs exercises

One thing we all want -- a slim midsection.
"One of the biggest misconceptions people have is the belief that they need to work five or six days a week to get their abs looking good. They also think they have to perform 15 sets. In reality, the muscles are like any other muscle group that needs to recover from any type of workout in order to make progress. Your abs workout shouldn't take you more than 12 minutes, three days a week."
In addition to working the abs, Raphael from eDiet stresses the importance of and regular cardio exercise. Before you can achieve a flat stomach, you need to reduce overall body fat.

1. Bicycle Maneuver
Starting Position:
 Lie on a mat with your lower back in a comfortable position.
 Put your hands on either side of your head by your ears.
 Bring your knees up to about a 45-degree angle.
Movement:
 Slowly go through a bicycle pedalling motion alternating your left elbow to your right knee, then your right elbow to your left knee.
Key Points:
 This can be a more advanced exercise. Do not perform this activity if it puts any strain on your lower back.
 Do not pull on your head and neck during this exercise.
 The lower to the ground your legs bicycle, the harder your abs have to work.

2. Abs Crunch
Starting Position:
 Lie on a mat on your back.
 Make sure that your lower back is relaxed against the mat during this exercise.
 Bend your knees until your legs are at a 45-degree angle.
 Keep both feet on the floor.
 Place both hands behind your head.
Movement:
 Contracting the upper abs, raise your head and upper torso off the floor until your shoulders are slightly lifted.
 Slowly return to the starting position, stopping just short of your head touching the floor.
Key Points:
 Exhale as you contract the abs.
 Inhale while returning to the starting position.
 Keep your eyes focused on the ceiling to avoid pulling with your neck.
 Your hands should not be used to lift the head or assist in the movement.

3. Reverse Abs Curl
Starting Position:
 Lie on the floor with your back relaxed and your hands on the floor by your hips.
 Keep the upper back pressed into the floor throughout the exercise.
Movement:
 Contracting your abs, raise your butt and gently roll your hips off the floor, stopping when you feel a full contraction of the abdominals and can no longer lift your hips.
 Slowly return to the starting position.
Key Points:
 Exhale while lifting your hips.
 Inhale while returning to the starting position.

4. Double Crunch
Starting Position:
 Lie on the floor face up.
 Bend your knees until your legs are at a 45-degree angle with both feet on the floor.
 Your back should be comfortably relaxed on the floor.
 Place both hands behind your head.
Movement:
 Contracting your abdominals, raise your head and legs off the floor toward one another.
 Slowly return to the starting position, stopping just short of your shoulders and feet touching the floor.
Key Points:
 Exhale while raising up.
 Inhale while returning to the starting position.
 Keep your eyes on the ceiling to avoid pulling with your neck.
 Your hands should not be used to lift the head or assist in the movement.


5. Cable Kneeling Rope Crunch
Starting Position:
 On a mat, kneel in front of the cable machine with your body facing the machine. Hold a rope attached to the upper cable attachment keeping your elbows in toward your ears.
Movement:
 Contracting the oblique muscles, curl your body downward on an angle rotating your right elbow to the left knee, stopping when you have reached a full contraction of your obliques.
 Slowly return to the starting position, stopping just short of the weight stack touching.
 You can either alternate side to side or do 8-12 repetitions on one side and then repeat on the other side.

Key Points:
 Exhale as you lift the weight.
 Inhale while returning to the starting position.

6. Machine Hanging Knee Raise (should use spotter or have someone watch you)
Starting Position:
 Grasp a chinning bar with hands shoulder-width apart and palms facing forward. Keep your upper body motionless throughout the exercise.
Movement:
 Contracting the abdominal muscles, raise your legs with bent knees while gently rolling your hips under, stopping when you feel a full contraction of the abdominals and can no longer lift your hips. You may get your knees to 90 degrees or higher depending on your strength and flexibility.
 Slowly return to the starting position.
Key Points:
 Exhale while lifting your legs.
 Inhale while returning to the starting position.

7. Fit ball Advanced Reverse Crunch (not for those with back injuries)
Starting Position:
 Lie on the ball with your upper back supported by the ball and hands above your head, holding onto a solid support, such as the support for a cable machine in the gym or the footboard of your bed at home.
 Bring your legs up until your hips and knees are each at a 90-degree angle.
Movement:
 Contracting the abdominals, curl your legs up toward your body.
 Slowly return to the starting position.
Key Points:
 Exhale while lifting your legs.
 Inhale while returning to the starting position.
 Lower your legs only as far as you can while maintaining control.

8. Lying Bent Knee Leg Lift (care needed for those with back injuries)
Starting Position:
 Lie on your back with your feet on the floor and knees slightly bent.
 Place your hands under your head for comfort, not support.
Movement:
 Contracting your lower abdominal muscles, draw your knees toward your chest until they form a 90-degree angle with the floor.
 Slowly return to the starting position, stopping just short of the feet touching the floor.
Key Points:
 Exhale while lifting your legs.
 Inhale while returning to the starting position.
 Your back should remain comfortably against the floor during the entire motion.
 Avoid this exercise if you have any back conditions.
 Eliminate this exercise if you experience any discomfort.

9. Machine Angled Leg Raise
Starting Position:
 Support your body on your elbows in a Roman Chair or by hanging from a chin-up bar.
 Movement:
 Contracting the abdominals and obliques, draw your knees up on an angle so that they move toward your right elbow. Stop when you get a full contraction of the obliques and abdominals.
 Slowly return to the starting position, stopping when the hips are almost fully extended.
 Alternate side to side to complete the set.
Key Points:
 Exhale while lifting your legs.
 Inhale while returning to the starting position.
 Keep the upper body stationary throughout the exercise.

10. Incline Bench Leg Raises (care needed for those with back injuries)
Starting Position:
 Lie on an incline bench and stabilize your body by gripping the bench above your head with your legs extended out.
Movement:
 Contracting the lower abs, raise your legs up until your hips form a 90-degree angle.
 Slowly return to the starting position, stopping just short of your legs touching the bench.
Key Points:
 Exhale while lifting your legs.
 Inhale while returning to the starting position.
 Point your chin toward the ceiling to avoid using your upper body.
 To increase the difficulty, cross your arms over your chest.

My personal experience:
Being a female myself, I find the followings are useful and practical and most importantly effective in tightening the abs within a short period of time.
1. Bicycle Maneuver. This is very simple and encouraging. In order to increase its difficulties, try to bring your body up higher each time when trying to touch your elbows to the opposite sides of your knees.
2. Abs Crunch.
3.Reverse Abs Curl whether on an inclined bench or on a mat. You can alternate the workout and I personally find it very effective to tone up lower abdomen.
4. Machine Angled Leg Raise on a Roman Chair.

You can choose any 3 combinations of the 4 choices above for each workout session.12 to 15 repetitions for 3 to 4 sets of each exercise. Again, from my experience, you can try to work out your abs on days when you do your cardio exercise.

Combining abs exercises with your main muscles groups strength training (chest, shoulders, lower body muscle groups) are too tiring and discouraging sometimes. By working out your major muscle groups, you are indirectly strengthening your core too.