Why Sit-ups are bad for you?

Core stability is a buzz phrase in rehabilitation circles and part of the core stability programme for the abdominal muscles often involves doing sit-ups or modified sit-ups (Crunches).

Professor Stuart McGill, a leading biomechanics researcher established that the compressive load on the lumbar spine when doing a sit-up or a crunch is in excess of 3300N (about 730lbs). The USA's National Institute of Occupational Safety and Health has set the action limit for low back compression at 3400N. It has been found that repetitive lifting loads that generate this sort of compressive force on the lumbar spine is linked to higher injury rates in workers.

So should we do abdominal exercises at all? Well, yes probably but it is a case of doing a safe exercise that doesn't potentially do us more harm than good. An example of a safe abdominal raise is demonstrated by the excellent Dr Phillip Snell in the YouTube video below. 

The jury is still out on what type of exercise helps back pain, however it is probably true that keeping active is better than not. Most people would be very surprised at the lack of evidence for any type of exercise as a therapy for back pain. 

From experience exercises help as long as they don't compress their spine considerably as so called flexion exercises do or indeed the traditional extension exercises do. Just keep active without doing any chores - delegation, that's the key!

For more on exercise see my Advice page.

For the National Institute of Occupational Safety and Health click here http://www.cdc.gov/NIOSH/