https://matteocampagna.com/en/registry/technique/arms-opposite-directions-release Changes to this claim in Matteo Campagna's evidence registry: its status, its year-by-year history, revisions of the page. en-gb https://matteocampagna.com/en/registry/technique/arms-opposite-directions-releaseOnly one study has measured it, in 2016, with two Malaysian university recurve archers wearing an accelerometer on each arm, eighteen arrows each at 70 metres. At the release both arms jolt on all three axes, and the peak displacement goes in opposite directions for the bow arm and the drawing arm on every axis, with one exception: the horizontal movement across the line of shot on arrows with a middling score. Vertically the bow arm drops and the drawing arm rises by almost equal amounts, around 2 to 3 centimetres, at every score level; along the line of shot the bow arm goes forward much further than the drawing hand goes back (6.8 against 1.2 centimetres on low-scoring arrows, 9.2 against 1.6 on high-scoring ones), except on the middling arrows, where the two movements are about the same. Whether the size of the movement tells you where the arrow goes is still open: the authors read a link in the movement across the line of shot, larger in the bow arm on low-scoring arrows and in the drawing hand on high-scoring ones, but the standard deviations are as large as the means and there is no statistical test. Two archers, accelerometers at about 15 Hz, displacements obtained by integrating acceleration twice: it is a description that gives the shape of the movement, not a measurement that can carry comparisons between arrows.claim:braccia-opposte-rilascio:revision:2026-02-23:2Mon, 23 Feb 2026 08:00:00 GMT https://matteocampagna.com/en/registry/technique/arms-opposite-directions-releaseclaim:braccia-opposte-rilascio:new_claim:2026-01-05:riportatoMon, 05 Jan 2026 08:00:00 GMT