Once upon a time in a faraway land, sit-ups were the standard for strengthening and tightening your core. Six-pack abs were made in the kitchen yes, but also with sit-ups.

Well things have changed and the sit-ups are so last year and they’ve been banished, never to return. According to livestrong.com sit-ups are now in the hot seat, with many trainers and experts claiming they are inefficient and cause more harm than good.

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Back and spine expert Dr Stuart McGill through years of surgery, according to the University of Waterloo in Canada, “found that crunches and traditional sit-ups place 340kg of compressive force on the spine when bent in flexion. These forces can squeeze a bent disc’s nucleus to the point that it bulges – pressing on nerves and causing back pain and potentially leading to a herniated disc.”

The Harvard Medical Health Journal suggests planking instead of sit-ups to strengthen and tighten your core, which includes more than just your stomach.

“Plank exercises recruit a better balance of muscles on the front, sides and back of the body during exercise than do sit-ups, which target just a few muscles. Through dynamic patterns of movement, a good core workout like plank exercises helps strengthen the entire set of core muscles you use every day” the journal states.