For some time now, core stability training has been a fitness-industry panacea. Without it, we are told, you risk poor posture, lower back pain, mediocre sports performance and a less than flat stomach.
But, says Spencer McGawley, a functional fitness and therapy specialist, "Many experts are adopting the view that core stability training is limited in its functionality. That's not to say it has no value at all, but it has been taken out of context, and its benefits wildly overplayed by the fitness industry."
The premise of core stability training is that certain muscles in the trunk and pelvic area have a role in protecting the spine and keeping the core of the body stable, thereby giving a solid foundation from which the limbs can work.
Core stability workouts target muscles that, so the theory goes, are lazy and do not "switch on" when needed. The main player is the transversus abdominis (TA), a muscle that wraps round the lower trunk, which is engaged by pulling the navel towards the spine in a move called "abdominal hollowing".
"Much of the focus on the TA came from Australian research which found that lower back pain sufferers had TA dysfunction," McGawley explains. This led to a belief that back pain was caused by the TA not "being recruited" in time to protect the spine during movement, and that isolating the core muscles would "retrain" them. The evidence to support this is equivocal.
A recent study from the University of Queensland found that isolation of the deep abdominal muscles could successfully improve recruitment patterns in lower back pain sufferers, while training the trunk muscles in a non-isolated manner (performing general abdominal exercises) could not.