• Sit-ups target your abdominal muscles, back muscles, and hip flexors, while crunches only target your abdominal muscles. • Neither sit-ups nor crunches alone burn abdominal fat. Overall activity and ...

Your abdominal muscles are resistant to fatigue, according to the IDEA Health & Fitness Association, a membership organization for fitness and wellness professionals. As part of your core muscles — ...

Add Yahoo as a preferred source to see more of our stories on Google. Credit: Getty Images GHD sit-ups are the type of advanced abs exercise reserved for those in the gym who like to send their core ...