Abs Exercise : The Situp

Forget that version of the situp you performed in grade school (the one in which you jerked your neck up like someone had just blown an air horn next to your ear). Instead, embrace the classic situp, and follow these guidelines on how to do it correctly from Nate Green, a trainer in Whitefish, Mont.

1 LIE ON YOUR BACK ON THE FLOOR, BEND YOUR KNEES 90 DEGREES, and plant your feet flat. Tuck your chin slightly toward your chest. Raise your arms off the floor so that they’re parallel to your body and pointing toward your feet.

2 KEEPING YOUR FEET AND BUTT ON THE FLOOR, RAISE YOUR TORSO OFF THE FLOOR and toward your thighs, coming up as far as you can (it’s OK to let your lower back come off the floor). The movement should be smooth; don’t jerk. Reverse the motion to return to the starting position. That’s one rep.

TROUBLE SHOOTERS

Correct these common problems for better situp form

YOU DON’T GO HIGH ENOUGH. Years of doing crunches may have taught you to raise only your head and shoulders off the floor. Nonsense. “Allow your lower back to round as you come up,” says Green.

YOU PULL YOURSELF UP BY YOUR NECK. It’s OK to place your hands behind your head, but don’t pull your head forward as you rise; it causes neck strain. “Start by pointing your arms straight forward [as shown at left],” says Green, “then you can progress to folding your arms across your chest, and then to cupping your hands around your ears.”

http://www.mensfitness.com/fitness/ab_exercises/212

Abs Exercise : The Plank

Get into pushup position on the floor. Now bend your elbows 90 degrees and rest your weight on your forearms. Your elbows should be directly beneath your shoulders, and your body should form a straight line from your head to your feet. Hold the position for as long as you can. Your goal should be to hold it for two minutes.
"The plank helps develop strength in the core, shoulders, arms, and glutes," says Scott, making it a great prerequisite for lifting heavy weights or playing intense sports. Even though you aren't moving or lifting weight, you have to constantly squeeze your abs to hold the position—most people can't last 30 seconds on their first attempt.
Ways to improve your plank time The longer you can hold the plank, the more resilient your lower back will be to injury, and the better your abs will look once you burn the fat off them. Follow these tips for longer plank times.

Practice: Perform planks several times each day, trying to hold the position a little longer each time.

Use body-weight exercises: Pushups and pullups will improve your core strength.

Squat and deadlift: Guys who are strong in these specific lifts find planks are no problem.
HOLD IT If you don't have the core strength yet to do a regular plank, you can build up to it by doing a bent-knee plank. If you can hold a plank for more than two minutes with ease, you can move on to these tougher variations.

Lift one leg up. By simply raising one leg in the air, you dramatically increase the demand on your core to fight your body's natural urge to rotate.

Lift one arm up. Again, your body will want to fall to one side. Don't let it!

Use a Swiss ball. Rest your forearms on the ball and you'll have to stabilize your body and stop the ball from rolling out from under you.

http://www.mensfitness.com/fitness/ab_exercises/459