In the last decade or so, it seems that working the core has become all the rage. Many believe the importance of a strong and stable core is the key to a stronger self. Some studies, however, conclude that core stability training is no better than any other form of trunk conditioning.
We can define the core as a group of muscles that stabilize or support the spine both statically or dynamically whilst other muscles carry out a movement that involves other joints. No one muscle or muscle group is more important than any other. If only one group of muscles is not functioning correctly, then we should conclude that the trunk is unstable.
No one argues that strengthening this muscle group would be detrimental to health and fitness. We should however think about the methods we employ to training this area given the role it plays around spine function and general back health. For example there are few good reasons for including sit ups within a core stability programme. The compression forces that are transmitted through the spine during this exercise have been recorded at 3500N+. That equates to more than 750lbs. Roman chairs, used to perform back extensions are believe to impose over 1000lbs of compressions on the spine. There is far less risk of injury when employing a gym ball correctly and a good personal trainer should be able to demonstrate good practise.
When using cable equipment to produce twisting or rotations of the spine, it is best to use a low load with full range of movement and higher loads with either static or small range. This again reduces compressions around the spine and promotes stronger, safer and more efficient movement.