While aiming, the bow sways more horizontally than vertically

The summary today

Three independent studies of archers find that the aim moves more horizontally than vertically. In 2005, in 12 Taiwanese archers at 70 metres, with a laser pointer on the grip, the aim over the last second and a half varies more horizontally in ten out of twelve, but with no test at all; in 2006, in 7 international-level junior recurve archers, the horizontal amplitude over the last second before the shot exceeds the vertical one in all seven, with a significant difference archer by archer; in 2010, in 4 elite Turkish women archers, the point of aim travels 13.0 centimetres horizontally across the target against 11.6 vertically over 108 arrows. A 2011 abstract suggests why: in 15 recurve archers the horizontal component is largely a slow drift, below 1 Hz, and is not linked to the score, while the vertical one is. There are two limits. The two studies that test the difference cover eleven archers in all, indoors, at 18 and 30 metres, and the outdoor one has no statistics; and the ratio between the two directions changes with the archer and with the instrument, so much so that in two of the twelve Taiwanese archers it is level or reversed, and in three German national team archers measured with an optical system on the bow the horizontal dominance shows up as a tendency in only one, while a video shot from behind makes it appear even where that system does not find it.

Also phrased as: "sideways sway while aiming"; "the sight drifting left and right"; "horizontal bow sway"; "lateral bow arm movement"; "horizontal and vertical hold box"

Evidence

• 2005
  For Archers Published later

  12 archers from the men's team of a Taiwanese college of physical education, 12 arrows at 70 metres, with a laser pointer on the grip tracing the aim onto a light target filmed on video: over the last second and a half before the release the standard deviation of the aim is larger horizontally than vertically in ten archers out of twelve, with ratios between the two directions ranging from 1.19 to 6.56; in the other two the ratio is 0.98 and 0.30. The study does not state the unit of measurement and runs no test on the difference: it is a description archer by archer (table 1, p. 257).

  Analysis of correlation between aiming adjustment trajectory and target · Kuo-Bin Lin, Chi-Kuang Hwang

• 2006
  For Archers Published later

  7 international-level junior recurve archers, 66 arrows at 30 metres indoors, with the aiming trajectory on the target recorded arrow by arrow and summarised as a rectangle, the 'hold box', with a horizontal and a vertical side: over the last second before the shot the horizontal side is longer than the vertical one in all seven (Wilcoxon, p < 5% for each archer), with mean values between 0.595 and 0.913 points against 0.412 and 0.647. In the window between two seconds and one second before the shot the difference is significant in only five archers out of seven.

  On‐target trajectories and the final pull in archery · Jürgen Edelmann‐Nusser, Mario Heller, Martin Hofmann, Nico Ganter

• 2010
  For Archers Published later

  4 elite Turkish women archers, 30 arrows each at 18 metres indoors, 108 of them usable, with the aim recorded on an electronic trainer alongside force plates and electromyography: from settling into the aim to the release the point of aim travels 13.0 ± 2.8 centimetres horizontally across the target against 11.6 ± 2.5 vertically (t = 4.5; p < 0.05). The difference is small, about a tenth, but it holds across the set of arrows.

  Shooting Dynamics in Archery · M. Emre Erkek, Cevdet Tinazci

• 2010
  Context Archers Published later

  3 German national team archers, 12 arrows each at 30 metres indoors, last second before the release, the same aim measured with three systems: with the optoelectronic system mounted on the bow, the study's reference, only the third archer shows a tendency to sway more horizontally, while in the first the two components are similar and in the second the horizontal dominance appears only in the video shot from behind. The aim was to compare instruments and there is no test of the difference between the two directions, but the data say that horizontal dominance is not the same for everyone and that filming from behind can make it appear.

  Comparing three methods for measuring the movement of the bow in the aiming phase of Olympic archery · Nico Ganter, Karl Christoph Matyschiok, Marcel Partie, Börge Tesch, Jürgen Edelmann-Nusser

• 2011
  For Archers Published later

  A second publication of the same experiment, with the same figures: 13.0 ± 2.8 centimetres horizontally against 11.6 ± 2.5 vertically (t = 4.5; p < 0.05) over 108 arrows, with 3.6 to 3.7 seconds on the target. Here the sample is described as male, in the 2010 version as female; in the registry the two papers count as a single study.

  Shooting dynamics in archery: A multidimensional analysis from drawing to releasing in male archers · Cevdet Tinazci

• 2011
  Context Archers Published later

  15 male recurve archers, from elite to sub-elite, with an accelerometer on the bow during a prolonged 10-second aim at a target 2.5 metres away: in horizontal tremor a large share of the power lies below 1 Hz, which makes it largely a slow drift, and horizontal tremor is not linked to the score, while vertical tremor is (r² = 0.26 for amplitude). The authors suggest that archers compensate for this slow drift at the release. It is a conference abstract.

  Biomechanical Predictors of Recurve Archery Performance · Martin H. Rose, Niels Dall, Kaare Seidelin, Bente R. Jensen

Status history

1. 2005 Reported The first measurement comes from twelve archers on the men's team of a Taiwanese college of physical education, twelve arrows at 70 metres, with a laser pointer on the grip tracing the aim onto a light target. Over the last second and a half before the release the aim varies more horizontally than vertically in ten archers out of twelve; in the other two the two directions are level or reversed. It is a description archer by archer, with no test at all, in a single study: reported.
2. 2006 Reported The second sample, independent of the first, is the first to put the difference to a test: 7 international-level junior recurve archers, 66 arrows at 30 metres indoors. Over the last second before the shot the horizontal amplitude of the aim exceeds the vertical one in all seven, with mean values between 0.60 and 0.91 points against 0.41 and 0.65, and the difference is significant for each archer; between two seconds and one second before the shot, by contrast, it holds for only five of the seven. Two studies now point the same way, but only one has a test and together they come to nineteen people: the status stays reported.
3. 2010 Reported A third sample arrives, independent of the previous two: in 4 elite Turkish women archers, 108 arrows at 18 metres, the point of aim travels 13.0 centimetres horizontally across the target against 11.6 vertically, from settling into the aim to the release (p < 0.05). Three studies of archers now point the same way, but the two with a test come to eleven people, indoors, and in the same year a comparison of instruments on three German national team archers finds, with the reference system, only a tendency towards horizontal dominance, and in just one of the three. The direction is consistent and the subjects are few: the status stays reported.
4. 2011 Reported The same Turkish experiment comes out in a second version, with the same figures, and counts only once. The new data come from another laboratory: in 15 recurve archers, with an accelerometer on the bow, horizontal tremor has a large share of its power below 1 Hz, which makes it largely a slow drift, and it is not linked to the score, while vertical tremor is. It is a hint as to why the horizontal component dominates, and that dominating does not mean mattering more, rather than a fresh confirmation: the status stays reported.

Related

Related articles

• The final pull: what happens in the last millimetres before the clickerHow many millimetres and seconds the final pull takes, how it differs between better and worse arrows, and what the aim and the muscles do as the clicker drops.
• Bow arm tremor in archery: why it happens and how to reduce itBow arm shake at full draw is two movements, a slow sway and a fast tremor. What the studies measure, where the tremor comes from and how to reduce it.

Research lines

• 48 studiesBow stability and aiming time: research since 1971
• 27 studiesTremor and sway while aiming: telling two phenomena apart since 1990

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