Spot reduction doesn't work. Sit-ups are definitely great for strengthening your abdominal muscles and lower back, but they have no impact on the body fat stored in those areas. If you want to lose weight from your waist, you need to lose it from all over your body.
Can doing 100 sit ups lose belly fat?
Unfortunately, even if you do 100 crunches a day, you won't lose the fat from your belly. The truth is, targeted fat loss — also known as spot reduction — is not possible, no matter how many crunches you do or products you buy. The only way you can lose fat from your belly is to lose fat from your entire body.
How many sit ups should i do a day to lose belly fat?
Health and fitness experts recommend that you do 100 situps per day and accompany that with a diet that is 500 calories less than your normal intake. That is one of the surest ways to lose a pound of belly fat in a week.