Sit-ups and crunches—if you’re working out to lose weight, you’ve probably tried both of these ab-exercises at least once. They’re simple, ab-sculpting workouts that only require your body ...

Both sit-ups and crunches can help target your core muscles, but there are key differences between the two ab workouts.

Sit-ups and crunches are both core exercises, but what makes them different? Here's a breakdown of crunches vs. sit-ups benefits, risks, and form per trainers.

Sit-ups and crunches Yes, the two moves look similar. Both require you to start in a supine position (face up), with your knees bent, feet flat and fingertips lightly touching behind your ears.

In his latest book, Sit-Ups Are Stupid & Crunches Are Crap, due out in April, he continues his work finding and treating the root causes of back pain, not just treating the symptoms.