Microcirculation Changes With Gua Sha
Using laser Doppler imaging, researchers found that a single Gua Sha treatment produced a roughly fourfold increase in local microcirculation that persisted for approximately 25 minutes, alongside a measurable reduction in reported myalgia — both at the treated site and, in some participants, at distant sites as well (Nielsen et al., 2007). The authors were careful to note that this distant-site effect could not be explained by the local circulatory change alone, pointing instead to a broader neurophysiological pain-modulating mechanism.
A Different, Deeper Effect With Instruments
Instrument-assisted soft tissue mobilisation (IASTM) uses a rigid tool to apply a more controlled and often deeper shear force to soft tissue than can typically be achieved with the hands alone. In an animal model, this kind of cross-fibre instrument work was shown to increase local tissue perfusion and measurably alter microvascular architecture in healing tendon tissue, consistent with a genuine, biologically active local response rather than a purely mechanical one (Loghmani & Warden, 2009). A systematic review of the broader IASTM literature found consistent short-term improvements in range of motion and pain, albeit from a body of research still limited by small sample sizes and short follow-up (Cheatham et al., 2016).
What This Means Clinically
Taken together, these findings support a genuine, biologically plausible local vascular and cellular response to both Gua Sha and IASTM, alongside broader neurophysiological pain modulation — a markedly more modest and more interesting picture than the folk explanations of "releasing" tissue or clearing toxins that are sometimes used to describe these techniques to clients.
References & Further Reading
- Nielsen A, Knoblauch NT, Dobos GJ, Michalsen A, Kaptchuk TJ. The effect of Gua Sha treatment on the microcirculation of surface tissue: a pilot study in healthy subjects. Explore (NY). 2007;3(5):456-466.
- Loghmani MT, Warden SJ. Instrument-assisted cross-fiber massage increases tissue perfusion and alters microvascular morphology in the healing digital flexor tendon. Phys Ther. 2009;89(12):1292-1303.
- Cheatham SW, Lee M, Cain M, Baker R. The efficacy of instrument assisted soft tissue mobilization: a systematic review. J Can Chiropr Assoc. 2016;60(3):200-211.