Sit-ups are one of the most popular core training exercises for people of all ages, but it turns out that sit-ups an’t such a good idea. A basic sit-up creates about 730 pounds of compression on the spine. Too many sit-ups and you could be dealing with serious spinal injuries instead of showing off your toned tummy. So in your quest for six-pack abs, avoid sit-ups and do crunches instead.
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