"Unfortunately, ab-specific workouts do NOT burn fat off of your belly. They only tone and strengthen the underlying abdominal muscles. What you really need to focus on is a full body strategic workout that will cause a much greater metabolic rate increase and fat-burning hormonal response from your training program as a whole.
In addition, simply doing cardiovascular workouts will not necessarily create the greatest metabolic response or hormonal response either. What you really need is a much more rounded training program that focuses on training the entire body with resistance training and multi-joint exercises in a higher intensity fashion.
A much smarter full body resistance training routine and a clean healthy balanced diet are the most important factors. Many of the full body exercises also indirectly work the abdominals and core due to the stabilization required in some of the more difficult variations.
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That summarizes it perfectly. I don't think yuo will find anyone here who will disagree with anything in the above excerp from that article.
Everybody is looking for the perfect exercsie routine, but the most important factors in progress are: NUTRITION, REST and CONSISTANCY.
After that the best exercises are the ones that have been around forever: basic heavy compound exercises: squat, deadlift, military press, pullup, bent row, bench press. Nobody has invented any new exercises or machines that are better than these.