Quantitative intramuscular myoelectric activity of quadratus lumborum during a wide variety of tasks
Two pages on PainSci cite McGill 1996: 1. Massage Therapy for Low Back Pain 2. Psoas, So What?
PainSci commentary on McGill 1996: ?This page is one of thousands in the PainScience.com bibliography. It is not a general article: it is focused on a single scientific paper, and it may provide only just enough context for the summary to make sense. Links to other papers and more general information are provided wherever possible.
An EMG study showing that quadratus lumborum is more involved in core stability than psoas, and is most active in a wide plank position. See also Andersson et al.
original abstract †Abstracts here may not perfectly match originals, for a variety of technical and practical reasons. Some abstacts are truncated for my purposes here, if they are particularly long-winded and unhelpful. I occasionally add clarifying notes. And I make some minor corrections.
Intramuscular fine-wire electrodes monitored the electromyographic activity of quadratus lumborum in four young adults. A wide variety of tasks were performed including flexion tasks, lateral bending, twisting, extension, and lifting tasks. Heavy lifts of barbell weights up to 70 kg activated the quadratus lumborum 74% of their maximum on average while surface recording of erector spinae (L(3)) were only 62% of their maximum activation. The quadratus lumborum was more active (54%) than other muscles during isometric side support postures where the body is held horizontally almost parallel to the floor as the subjects supported themselves on one elbow on the floor together with both feet. Furthermore, it increased activation in response to increasing compression in static upright standing postures. Electromyographic evidence, together with architectural features make the quadratus lumborum a better stabilizer of the spine than psoas. Use of horizontal ‘side support’ exercise to train this muscle would appear to be a wise choice.
related content
- “EMG activities of the quadratus lumborum and erector spinae muscles during flexion-relaxation and other motor tasks,” Andersson et al, Clin Biomech (Bristol, Avon), 1996.
- “Anatomy and biomechanics of quadratus lumborum,” Phillips et al, Proc Inst Mech Eng H, 2008.
- “Heterotopic ossification of the quadratus lumborum muscle,” Alport et al, J Radiol Case Rep, 2014.
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- Recovery trajectories in common musculoskeletal complaints by diagnosis contra prognostic phenotypes. Aasdahl 2021 BMC Musculoskelet Disord.
- Cannabidiol (CBD) products for pain: ineffective, expensive, and with potential harms. Moore 2023 J Pain.
- Moderators of the effect of therapeutic exercise for knee and hip osteoarthritis: a systematic review and individual participant data meta-analysis. Holden 2023 The Lancet Rheumatology.