Do one to two sets of reverse crunches with 12 reps. The movement should be controlled and slow. Do not let your legs drop during the downward phase.
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Jack Knife Sit Ups
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Do two to three sets of 15 reps of jack knife situps. It is the most basic exercise for six-pack abs and it engages the sides of the abdomen, intercostals and external oblique.
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Long-arm crunches
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Do 15 reps of the long-arm crunches. Extending your arms while crunching will make your crunches more efficient.
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Extended plank
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Hold the extended plank position for 50 seconds. This is one of the most effective workouts for 6-packs. It is similar to the traditional plank, but here you exert more force on the muscles of your abs.
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Janda Sit-Up
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Do two sets of janda sit-up with 12 reps. It is not a very popular exercise. Janda sit-up will help in strengthening your abdominal muscles.