Sit-ups may seem old school. But, when done correctly, they're effective and that's why they've stood the test of time. Late-night infomercials and different workout programs have tried to improve upon the basic sit-up for years. But you don't need any $19.99, plus shipping and handling, tool to get the job done.

Safe and effective sit ups are as simple as ABC ... and D. (Though that darn 'D' makes the whole shtick a lot less catchy.)

• A is for Alignment. Lie on your back with your knees bent. Keep your feet flat on the floor and don't hook them under your couch or anything else. Position the small of your back flat on the floor. With your hands resting lightly on your temples (not behind your head -- pulling can injure you), lift your head, neck and shoulders off the ground.
  
• B is for Body control. When lifting up, make sure your abs are doing the work. Go slowly. Remember to breathe while doing the sit-up.
  
• C is for Consistency. Don't expect a few sit-ups once a month to do the trick. Try doing sit-ups every other day, and remember that quality is better than quantity -- 10-20 with proper form are better (and safer!) than many sloppy ones.
  
• D is for Develop all the abdominal muscles. Traditional sit-ups don't target the lower abdominal muscles and you don't want them to feel left out, do you? Try lying on your back with your knees bent, then bring one knee toward your chest and hold for a few seconds. Bring the other leg up and then slowly lower the first leg, then the second. Repeat on both sides.
  

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If you are having trouble balancing during certain exercises using a spotter is a good idea until you build up body muscles that will hold you for that particular exercise. Spotters are not just for weight lifting.

One of the most important things to know with exercise is proper body alignment and balance. Maintaining a good position with your head so that you are not pulling on your neck while doing sit ups or other ab exercises is important to reduce your risks of injuries. If you're doing a set of abdominal exercises and your neck hurts but not your stomach then you might want to look and see how you were lying or how you were holding your head because you're neck shouldn't hurt after you've been doing abdominal exercises. You need to check your body alignment. If you are holding your hands behind your neck and you're actually irritating your neck or straining then you are doing either too much or trying to go too fast and you are straining and that is creating stress on your neck.

One of the top exercises that you can do for abs is a reverse crunch. Lie down on a bench with your knees bent and your upper legs at a 90 degree angle with your torso. Hold the bench above your head for stability. Use your ab muscles to pull your knees toward your chest until they reach your elbows. Hold the crunch position for three seconds and return to the starting position. Doing ten of these in your exercise routine every day will give you a toner midsection.

Posture is one of those things everybody should think about, but only a few people really do. "Standing up straight" will not only benefit you physically by reducing back and joint stress, but it can also help elevate your general mood and outlook, and even (perhaps best of all) help you look up to 10 pounds slimmer.

Improving your posture is more about being conscious of it than anything else, but here are some exercises you can do to help you to be more aware of your body alignment and strengthen the appropriate muscles.

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