When it comes to abs and looking good naked, you probably care most about your rectus abdominis (six-pack muscle) and your external obliques (the area that helps form the top of the "V" that points towards your junk).

Although working your entire core can be part of a well-rounded program, you'll need to place extra focus on exercises that activate your abs to their full capacity. And while having low body fat is an important part of it, you need to subject your abs to hypertrophy training to get more dense and deeply etched lines.

Here's a nasty version of the crunch using an ab mat to take your abs through a greater range of motion:

How to Do It

  1. Pick a weight that you can get about 10-15 weighted crunches with, then get yourself in position.
  2. Create an internal focus. Think about pulling your ribs toward your pelvis and contracting that space in the middle as hard as you can throughout.
  3. When you get a few reps shy of failure, get rid of the weight.
  4. Continue with hands overhead until you reach near failure again. Stay focused on what you're trying to work.
  5. Continue to do the same with hands on your head, then move them to your sides.
  6. Finish with an iso-hold at the top.
  7. That's one set. Now do two to three.

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