Is your ab workout hurting your back?

In those with healthy backs,the scientists found,a deep abdominal muscle tensed several milliseconds before the arms rose. The brain apparently alerted the muscle,the transversus abdominis,to brace the spine in advance of movement. In those with back pain,however,the transversus abdominis didnt fire early. The spine wasnt ready for the flailing. It wobbled and ached. Perhaps,the researchers theorised,increasing abdominal strength could ease back pain.

Thereafter,the idea leaked into gyms that core health was all about the transversus abdominis, said Thomas Nesser,an associate professor of physical education at Indiana State University.

Personal trainers began directing clients to pull in their belly buttons during crunches.

But theres growing dissent among sports scientists about whether all of this attention to the deep abdominal muscles is even safe. An article published in the The British Journal of Sports Medicine last year asserted that some of the key findings from the first Australian study may be wrong. Moreover,even if they were true for people in pain,they may not apply to the fit,whose trunk muscles werent misfiring in the first place.

The idea has reached trainers and through them the public that the core means only the abs. Theres no science behind that idea, maintains Stuart McGill,professor of spine biomechanics at the University of Waterloo.

The core remains a somewhat nebulous concept; but most researchers consider it the corset of muscles and connective tissue that encircle and hold the spine in place. If your core is stable,your spine remains upright while your body swivels around it.

But,McGill says,if you concentrate on strengthening only one set of muscles in the core,you can pull your spine out of alignment.

Instead,he suggests,a core exercise programme should emphasise all the major muscles that girdle the spine,including but not concentrating on the abs. Side plank lie on your side and raise your upper body and the bird dog in which,from all fours,you raise an alternate arm and leg.

As for the abdominals,no sit-ups,McGill said. They place devastating loads on the disks.

An approved crunch begins with you lying down,one knee bent,and hands positioned beneath your lower back for support. Do not hollow your stomach or press your back against the floor, McGill says. Gently lift your head and shoulders,hold briefly and relax back down.

These three exercises,done regularly,McGill said,can provide well-rounded,thorough core stability. I see too many people, McGill said,who have six-pack abs and a ruined back.