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I'm assuming your doing the perfect posterior workout. In which case you should be doing those exercises 3x/week. The abs are twice a week. I've setup my routine to overlap a little. M/W/F I do kettlebell swings after a run in the morning. On the M/F I throw in the ab exercises.
You don't want to focus on your abs to much, they get a workout from your day to day activities, not to mention the kettlebell exercises...
I'm fairly active, so I would say start slow. See what half the reps feel like and just sort of buildup each week. Before you know it, you'll be completing the full sets and wondering where to go next!
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