Whenever possible, add resistance to your ab exercises with weight. Most people increase the load on exercises for major muscle groups but they don't on ab exercises. That's a mistake. Think ankle weights for leg raises or a 45-pound plate for crunches as shown here.
related posts
Biomechanical Advantage - Part 2
How you could stretch out a set by making use of the fact that you can give yourself a biomechanical advantage simply by changing your foot or hand position.
T Nation May 25
Shoulders and Triceps Blast
A 6-week routine filled with heavy weights, drop sets, and 100-rep muscle burners. You ready?
Tim Henriques February 13
20 Training Tips From John Romaniello
Break out the tape measure and get ready to hit the gym. Roman's got some tips to make this your best training year ever.
Nate Green July 5
Tip: The Best Grip For Pain-Free Pressing
Here's how to find your best grip on dumbbell bench presses, a grip that'll allow you to press without pain AND build muscle.
Dr John Rusin October 11