Situps and crunches are exercizes commonly used to strengthen the abdominal muscles. People often measure their fitness by how many they can do at once. As our understanding of the body has grown, we've seen that common ideas about fitness need updating.
Dr. Stuart McGill is a highly regarded professor of spine biomechanics at the University of Waterloo in Canada. He argues that situps and crunches, exercises which require you to "fold in" or hollow your belly, lead to injury of the spine.…Read more→