Sit-ups, Sit-ups, Sit-ups, Sit-ups, Sit-ups, Sit-ups, Sit-ups, Sit-ups, …. and more Sit-ups.

It really depends on two things, how much of that 160 pounds is fat and how defined you want your six pack to be.

For example-

If you want just enough that you can see the abs but the lowest two are barely defined, it can take as little as a month with one hour every two days if you don’t have much fat on you.

On the other hand, if you want abs like King Leonidus (I believe the actor is Gerard Butler) in 300, it’ll take 6 hours a day for 8 months.

As was said, it is important to do different type of crunches to build the muscle. But, you’ll never see that muscle you built if you have fat over it, and that’s where the cardio come in. You need to combine diet, cardio and ab exercise if you want a six pack.

Good luck.

actually they r allready there.u just lose stomach fat and they appear.to get em more robust takes ages.i used to do 600 crunches 5 days a week which takes 13 minutes,and it took 6 months b4 i got my 1st compliment.

Using a number of different crunch excercises are key, I have found that hanging crunches, bosu ball crunches while holding a medicine ball, and push ups (keeping stomach tight of course) are very effective in building the abdominal muscles.

The key to getting the six pack is to mix excercises (like those above) with a lot of cardio. Try box jumps between sets and finishing your workout on the elliptical machine or the bike.

ps check out menshealth.com — they have videos too

Do sit-ups/crunces everyday..and try going jogging..

are you single and ready to mingle?