Situps, in and of themselves, will not make your waist smaller. Spot reduction -- exercising a particular body part to trim inches -- has been proven a myth. That said, situps, or crunches, are a good exercise for strengthening your core, and if combined with a routine of regular cardio and strength training will help you lose fat as you burn calories and increase your metabolism. You will be losing fat from your whole body, and while abdominal fat can be hard to shed, with discipline in your exercise and diet, you will see results.
Abdominal Fat
There are two kinds of fat in the abdomen: subcutaneous fat, which is the fat you can pinch with your fingers, and visceral fat, which surrounds the internal organs. Of the two, visceral fat poses the greatest health risks, as it has been linked to cardiovascular disease, type 2 diabetes, breast cancer and the need for gallbladder surgery. The good news is that visceral fat responds to exercise and diet more quickly than subcutaneous fat.
Core Strengthening
Situps, plank exercises and bridge poses -- or any exercises that involve coordinated use of muscles in your back and abdomen -- are core exercises. With a strong core, you will have better balance and will find it easier to do most activities, whether it is something as mundane as bending down to tie your shoelaces or doing weight training in the gym. A strong core also helps prevent some back pain and poor posture.
Recommended Exercise Routine
According to the CDC, at minimum you should do 150 minutes of aerobic exercise a week, in combination with muscle-strengthening exercises that focus on all muscle groups at least 20 minutes, two days a week. If you are trying to trim fat and gain even more health benefits, you should consider upping that to 300 minutes a week of moderate-intensity cardio in combination with the aforementioned two days of strength training. You can break the cardio into frequent short segments of at least 10 minutes if you are pressed for time.
Other Tips
Incorporate different types of core exercises in your routine to tone the muscles of the abdomen. Even though you won't see immediate results in your waistline, you will be bringing definition and strength to those muscles. As you burn calories and lose fat, that definition will show. Stay away from refined carbs and sugars and increase the lean proteins and complex carbs in your diet. Use portion control; it is better to have small amounts of food more often throughout the day than large meals consumed less often.
References
Writer Bio
Based in New York City, Rebecca Jones has been a writer, reporter and researcher for more than 20 years. Her reporting and researching has helped inform the pages of Glamour, Giant, and Ladies' Home Journal among other publications. In addition to her professional work in the editorial departments of magazines, Jones is an avid poet and as yet unpublished fiction writer.