Developing a six-pack takes months of dedicated work, but two weeks is enough to start building the sort of healthy habits that will eventually get you to your goal. If you want other people to be able to admire your abdominal definition, you must not only strengthen your abs but also eat and exercise to reduce your body fat. It's the combination of a lean body and well-developed abdominals that let the natural structure of your rectus abdominus -- the much-desired six pack -- show through.
You'll achieve your goal of six-pack abs much faster if you focus on doing the most effective abdominal exercises. According to a 2001 study sponsored by the American Council on Exercise, some of the most effective exercises include bicycle crunches, hanging knee raises on the captain's chair, crunches on an exercise ball and crunches with your legs straight up in the air.
One to three sets of 10 to 25 repetitions is a good general target for any ab exercise. But if you'll meet your six-pack goal much more quickly if you stick to the lower end of that range, using weights or more difficult exercise variations to make a challenge out of completing 10 to 15 repetitions with good form.
Like any other muscle, your abdominals require at least 24 hours of rest time between workouts. Taking the time to rest will help you meet your goal faster, because your muscles get stronger during rest time between workouts, not during the workouts themselves. Aim for three ab workouts every week with at least one day of rest between each; if you're still sore when the next workout rolls around, either decrease the intensity slightly or cut back to two intense workouts per week.
In addition to your abdominal workouts, you must also do enough cardio workouts and strength training to burn more calories than you take in. This calorie deficit is what causes weight loss; for every 3,500 calories burned beyond what you take in, you burn a pound of fat. But if you skimp on your diet, your body won't get what it needs to build that six pack you're looking for. The Centers for Disease Control and Prevention recommends eating for a healthy weight by focusing on fruits, vegetables and whole grains, along with lean protein sources, beans and nuts.
If you're not used to regular workouts and clean eating, it may take some time to get used to the idea. Some people may be able to make and maintain a drastic lifestyle change, but most will enjoy greater -- and longer-lasting -- success if they use the first couple weeks of their program to gradually ease into it, starting with shorter, easier workouts and gradually ramping them up until you reach your goal. In a similar vein, start with small changes to your diet and, as you maintain them, continue making small adjustments until you hit your ideal diet.