Situps and crunches are two antiquated exercises that should have been replaced with safer and more effective abdominal muscle building workouts long ago.

Why are they bad? For one, situps and crunches are both performed laying down on your back and then repeatedly bending the spine. The spine can only take so much before back pain manifests in the form of bulging discs and disc herniations. Lower back strain is all too common because of the constant rounding of the back during these movements.

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