In high-level archers the bow does not move measurably while the arrow is still on the string

The summary today

Two high-speed measurements point the same way, but only one looks at a group. At the London Olympic test event in 2011, sixteen world-class recurve archers were filmed at 4,000 frames per second while shooting at 70 metres: in all sixteen the bow moved no more than a millimetre sideways, and rotated no more than a tenth of a degree, until the arrow had left the string. A Korean study from 2007, at a thousand frames per second, finds the same in the archer then ranked second in the world, with zero displacement, while the bow of a university archer moves by one or two tenths of a millimetre. As early as 1998, with an accelerometer at the centre of the bow, the first peak in acceleration came 6 to 8 milliseconds after the arrow left the string. The limits are clear: the one-millimetre threshold is the camera's, the Korean comparison is between two people, in a regional journal and with figures in the text that do not match the table, and nobody has measured a group of lower-level archers, where the only case observed did move.

Also phrased as: "the arrow leaves before the bow moves"; "bow movement at the release"; "the bow only moves after the arrow has gone"; "power stroke and bow movement"; "bow reaction at the release"

Evidence

• 1987
  Context Archers Published later

  Abstract of a method from the Institute of Sport Science in Rome: clicker, button and nock become electrical switches and an accelerometer on the riser records the lateral acceleration of the bow while arrow and string are still in contact. It is the first instrument built for exactly this question, but the abstract reports no data and neither the number of archers nor the number of shots.

  A new method to measure lateral bow displacement during shooting in archery · C. Gallozzi, L.M. Leonardi, A. Pace, G. Caselli

• 1998
  Context Archers Published later

  German national team archers, with an acceleration sensor at the centre of the bow synchronised with high-speed video: the arrow leaves the string 6 to 8 ms before the first peak of the bow's acceleration curve. It indicates that the strong reaction of the bow comes after the arrow has gone, but it does not measure the bow's displacement beforehand.

  Coordinative Aspects of Archery - An Approach Using Surface-Electromyography · Jürgen Edelmann-Nusser, Albert Gollhofer

• 2007
  For Archers Published later

  The archer then ranked second in the world, 60 arrows at 70 m, filmed at 1,000 frames per second: between the release and the arrow leaving, the bow moves 0.00 mm both front to back and up and down. The university archer used for comparison shows 0.14 ± 0.03 and 0.20 ± 0.08 mm according to the text, but 0.18 ± 0.06 and 0.14 ± 0.08 mm according to Table 1: the figures do not match within the paper. Supporting only for high-level archers; a single case, in a regional journal.

  Evaluation on Motion Features of the World's Second Archer during Back-Tension in Archery · J.-H. Yi, C.-K. Hah, J.-S. Ryu, K.-C. Kim

• 2012
  For Archers Published later

  16 world-class recurve archers (8 women, 8 men) at the London 2011 Olympic test event, filmed from above at 4,000 frames per second while shooting at 70 m: in all 16 the bow moved no more than one pixel sideways, at most 1 mm, and rotated certainly less than 0.1 degrees about the vertical axis of the grip before the arrow left the string. Afterwards the bow hand usually drops slightly. The threshold is the camera's resolution, and the measurement covers only sideways movement and rotation.

  High-speed video analysis of arrow behaviour during the power stroke of a recurve archery bow · James L Park, Oliver Logan

Status history

1. 1987 Not studied A group in Rome presents the first method designed to measure the lateral displacement of the bow while the arrow is still on the string: clicker, button and nock wired as switches and an accelerometer on the riser. The abstract describes the instrument but reports no results, so the question now has a way to be measured and still no data.
2. 1998 Not studied The first measurement with figures close to the question comes from nine German national team archers, with an accelerometer at the centre of the bow and high-speed video: the arrow leaves the string 6 to 8 milliseconds before the first peak in the bow's acceleration. It shows that the strong reaction of the bow comes afterwards, not whether there is any measurable displacement before: nobody has yet measured how much the bow moves while the arrow is on the string.
3. 2007 Reported Filmed at a thousand frames per second, between the release and the arrow leaving, the bow of the archer then ranked second in the world does not move, either front to back or up and down, while that of a university archer moves by one or two tenths of a millimetre. The comparison is between two people, in a regional journal, and in the paper the figures in the text do not match those in the table: there is evidence in favour, for high-level archers, and it is limited.
4. 2012 Reported Sixteen world-class recurve archers, filmed at 4,000 frames per second at the London Olympic test event: in all of them the bow moves no more than a millimetre sideways and rotates no more than a tenth of a degree until the arrow has left the string. The supporting studies become two, but the first is a single case in a regional journal and the second is descriptive, with a threshold set by the camera: the status stays reported.

Related

Related articles

• The bow hand: where it pushes, how much it closes and how much torque mattersHow the hand sits on the grip, how much expert archers squeeze, and what the measurements say about grip pressure, its consistency and bow torque.
• Stabilisers in archery: what they actually do, beyond the folkloreWhat research has measured about stabilisers: how the bow moves at release, muscle work, vibration, barebow weights and accuracy.
• The follow-through: what happens after the arrow has goneIn the top archers measured, the arrow leaves the string in about 15 milliseconds. What the body does next, what studies have found and where they stop.

Research lines

• 24 studiesThe passive release: fifty years to take an idea apart
• 54 studiesMovement variability and individual technique since 1971

Other claims in this domain

• CorroboratedBetween one and a half and two tenths of a second pass between the clicker sounding and the arrow leaving7 studies · 94 archers measuredStatus since 1990
• ReportedA camera diagonally behind the archer measures the vertical sway of the aim well, but not the horizontal1 study · 3 archers measuredStatus since 2010
• ReportedA continuous final pull through the clicker leads to better shots9 studies · 56 archers measuredStatus since 1993
• ReportedA sound or light cue about the angle of the bow arm tightens beginners' groups2 studies · 1 archers measuredStatus since 2012
• ReportedA thumb grip on the string is less tiring than a finger grip3 studies · 9 archers measuredStatus since 1990

See all claims on technique and biomechanics