Getty ImagesThe genesis of much of the ab work we do these days probably lies in the work done in an Australian physiotherapy lab during the mid-1990s. Researchers there, hoping to elucidate the underlying cause of back pain, attached electrodes to people’s midsections and directed them to rapidly raise and lower their arms, like the alarmist robot in “Lost in Space.”
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 didn’t fire early. The spine wasn’t ready for the flailing. It wobbled and ached. Perhaps, the researchers theorized, increasing abdominal strength could ease back pain. The lab worked with patients in pain to isolate and strengthen that particular deep muscle, in part by sucking in their guts during exercises. The results, though mixed, showed some promise against sore backs.
From that highly technical foray into rehabilitative medicine, a booming industry of fitness classes was born. “The idea leaked” into gyms and Pilates classes that core health was “all about the transversus abdominis,” Thomas Nesser, an associate professor of physical education at Indiana State University who has studied core fitness, told me recently. Personal trainers began directing clients to pull in their belly buttons during crunches on Swiss balls or to press their backs against the floor during sit-ups, deeply hollowing their stomachs, then curl up one spinal segment at a time. “People are now spending hours trying to strengthen” their deep ab muscles, Nesser said.
But there’s growing dissent among sports scientists about whether all of this attention to the deep abdominal muscles actually gives you a more powerful core and a stronger back and whether it’s even safe. A provocative article published in the The British Journal of Sports Medicine last year asserted that some of the key findings from the first Australian study of back pain might be wrong. Moreover, even if they were true for some people in pain, the results might not apply to the generally healthy and fit, whose trunk muscles weren’t misfiring in the first place.
“There’s so much mythology out there about the core,” maintains Stuart McGill, a highly regarded professor of spine biomechanics at the University of Waterloo in Canada and a back-pain clinician who has been crusading against ab exercises that require hollowing your belly. “The idea has reached trainers and through them the public that the core means only the abs. There’s no science behind that idea.” (McGill’s website is backfitpro.com.)
