Testing our servicemen and women for physical fitness has long included the sit-up as a measuring stick for core strength. This despite the fact that the evidence indicates the forward-bending or flexion movement of the lower back performed in the process of the sit-up is potentially harmful to the lower back. There are better exercises to measure core strength, e.g. planks, and other fitness tests that can better measure the capacity to perform their jobs. This approach has been adopted, in part, by the Marines where testing includes more functional measures that better mimic the actual requirements of their job, such as a 50-yard loaded carry to test their capacity to carry an injured person out of harm’s way. The Navy is now moving in this direction; read more about these changes in the Navy Times.