At the release the fingers open mainly at the middle and end joints, and barely at the knuckles

The summary today

The measurement exists, but on one archer. In 2009 eight infrared cameras filmed, at 500 frames per second, the fingers of an archer from the Austrian B team, aged 49 with an indoor record of 1131 out of 1200, over 56 usable shots at 18 metres. The knuckles, the joints at the base of the fingers, barely move, between 6 and 9 degrees, while most of the opening happens at the two outer joints. The finger that moves most is the index, 81 degrees in all, followed by the middle finger with 58 and the ring finger with 48, and the leading joint is not the same in every finger: in the index and ring fingers the end joint does most of the work (52% and 57% of the finger's range), in the middle finger the middle joint (55%). A second paper in 2011 re-reads the same arrows and confirms the ranges; it adds that on poor shots the curve of the middle finger's base joint strays further from the group average than on good shots, so the very joint that moves least is the one that changes most between a good shot and a poor one. It is a careful description of a single three-finger release: it does not say whether it holds for other archers, other levels or other grips.

Also phrased as: "how the fingers open at the release"; "the knuckles at the release"; "hook release"; "finger joints and the release"; "the fingers should not open"

Evidence

• 2009
  For Archers Published later

  An archer of the Austrian B team shooting recurve, aged 49, indoor record 1131 out of 1200, filmed by eight infrared cameras at 500 frames per second: 56 usable shots out of 90 at 18 m. The joints at the base of the fingers move between 6 and 9 degrees, 11 to 13% of the finger's range; the middle and end joints do the rest (index 30 ± 2 and 42 ± 5 degrees; middle 32 ± 2 and 19 ± 2; ring 15 ± 2 and 28 ± 4).

  A Kinematic Analysis of Finger Motion in Archery · B. Horsak, M. Heller, A. Baca

• 2009
  Context Archers Published later

  In the same archer the index is the finger that moves most (81 ± 5 degrees in all), then the middle finger (58 ± 3) and the ring finger (48 ± 5), and the leading joint changes from finger to finger: the end joint in the index (52 ± 6% of the range) and ring finger (57 ± 9%), the middle joint in the middle finger (55 ± 4%). The speed at which the middle finger's middle joint opens does not separate the better arrows from the worse ones (p = 0.870 and p = 0.221).

  A Kinematic Analysis of Finger Motion in Archery · B. Horsak, M. Heller, A. Baca

• 2011
  Context Archers Published later

  The same 56 arrows from the same archer, re-read in 2011: the ranges are the same (81, 58 and 48 degrees; knuckles between 6 and 9) and the study counts once. Splitting the shots into good (10 or inner ring, 12 arrows) and poor (8 or less, 18 arrows), the curve of the middle finger's base joint varies more on the poor shots (t = -2.98, p = 0.006), while the middle joint (p = 0.122) and the end joint (p = 0.545) do not.

  A Three-Dimensional Analysis of Finger and Bow String Movements During the Release in Archery · Brian Horsak, Mario Heller

Status history

1. 2009 Reported The first data come from an archer of the Austrian B team filmed at 500 frames per second over 56 arrows at 18 metres: the joints at the base of the fingers move 6 to 9 degrees, the middle and end joints 15 to 42 depending on the finger, and the index opens almost twice as far as the ring finger. In the index and ring fingers the end joint leads, in the middle finger the middle joint. It is a single case, carefully described: reported.
2. 2011 Reported The same authors re-read the same 56 arrows: the ranges are the same, so the study counts once. The new part is variability: on poor shots the curve of the middle finger's base joint strays further from the group average than on good shots (p = 0.006), while the other two joints do not. There is still a single case, and the status does not change.

Related

Related articles

• The string grip: what changes between two fingers, three fingers and the thumbTwo fingers, three fingers or the thumb on the string: what studies have measured on grouping, steadiness, muscles and release, and where the data stop.
• The release in archery: anatomy of a few millisecondsHow the archery release works according to the measurements: how long it lasts, how the fingers open, what the arrow does and what you can train.

Research lines

• 24 studiesThe passive release: fifty years to take an idea apart
• 9 studiesThe string grip: fingers, thumb and thirty years of comparisons

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