Sit-up is the most popular AND yet, the worst ab exercise. Most people don’t know that sit-up is not a true ab exercise. When performing a sit-up, your main trunk flexor, the iliopsoas muscle, often does the majority of the work while the abs are not fully recruited.
The iliopsoas muscles originates on the lower back so it pulls on the lower back during every repetition of sit-up, especially when your feet are held down or anchored, or repetitions are performed in a jerky manner. Too many sit-ups can lead to strength imbalance between iliopsoas and abs, poor posture and lower back pain.
People who hold weights while doing sit-ups think that helps to build their abs. Unfortunately, they increase the chances of lower back injury significantly. The iliopsoas muscles work much harder and place even more strain on the lower back than bodyweight sit-ups. Additional weight may lead to poor exercise form, thus amplifying the likelihood of injury.
Crunches are another common ab exercise. Doing hundreds of crunches alone and regularly can pull your head forward and leave your spine slightly flexed (leading to hunch back). You end up with poor posture and lower back pain.
If you don’t overuse crunches, they can still be an effective ab exercise. Vary your ab workout just like you vary your cardio and strength training exercise.
There are plenty of safe and effective ab exercises for conditioning and strengthening your abs, which many people are not aware of. They include total body exercises that work the abs and swiss ball workout.
Believe it or not, you can develop amazing abs without ever doing a single sit-up!
