No one really likes doing their crunches, and there might be better exercises, but sit ups can still be a very effective core strengthener. Utilize this little tip and get more bang for your crunching buck. When doing crunches exhale forcefully at the top of the movement. The action causes your abdominal muscles to work harder and you get a deeper, tighter contraction. Think about breathing out hard, almost emptying your stomach and bringing your bellybutton towards your spine. That said, crunches aren't for everyone. If you experience any sort of lower back pain and discomfort during your day or while doing crunches they are best left out. Faulty biomechanics or under-activated muscles while doing hip flexion exercises can cause disc herniation. Even if you can do crunches without worry make sure they aren't the only core exercise you are doing. Supplement with variations of plank, leg raises and oblique exercises. For more fun facts join me on Facebook.