Field card: Technique and biomechanics
An A4 sheet to take to the range: the terms that recur in the studies in this domain, with a one-line definition, and the registry claims that are currently corroborated, contested, contradicted or refuted.
It fits on a single A4 sheet. You can also print with Ctrl+P, or Cmd+P on a Mac.
Terms
- Clicker
- The thin blade mounted on the riser that the arrow sits under.
- Draw length
- The distance at full draw from the bottom of the nock groove to the pivot point of the grip, with a small fixed amount added by convention.
- Anchor
- The fixed point on the face where the drawing hand settles at full draw, for example under the jaw with the string touching chin and nose in Olympic recurve.
- Electromyography (EMG)
- Electromyography records the electrical activity of muscles as they work.
- Phases of the shot
- The division of the shot into phases, usually raising the bow, drawing, anchoring, aiming with the final pull, release and follow-through.
- Tremor and force steadiness
- Tremor is the fast, involuntary oscillation of the bow arm, and with it the bow, while the archer holds the aim.
- Postural sway and centre of pressure
- The small, continuous movement of the body even while aiming; the centre of pressure is the point under the feet where all the body's weight can be taken to act.
- Follow-through
- What the archer does after the release.
- Stance
- The position of the feet on the shooting line: square, open, closed or oblique.
- Dominant eye
- It is the eye the brain favours when looking at a distant point, and it is normally the one an archer aims with.
- Final pull (expansion)
- The last short stretch of the draw, made after reaching anchor while aiming; in Olympic recurve it is a matter of a few millimetres and ends when the clicker snaps.
- Creeping
- When, under the clicker, the draw shortens and the arrow slides forward instead of continuing to move back.
Claims
- Corroborated From 1987 to 2020 six independent groups measure 120 to 240 milliseconds from clicker to release; the more recent figures sit between 140 and 165.
- Contested Three studies find more weight on the front leg at full draw and two find more on the back leg: the most recent suggests it depends on how the feet are placed.
- Contested A small experiment on beginners finds an advantage in shooting from both sides, while a comparison of competitive archers finds no difference in score.
- Contested Two studies of Indonesian archers give opposite answers on varied distance training, and the only one in favour appeared in a journal of questionable standards.
- Contested In expert archers the score at competition distances follows the line of the other distances, except 70 metres in men.
- Contested Eight weeks of exercise brought the elbow closer to the line of force without raising the score, and among elite archers the angles do not tell arrows apart.
- Contested In a single group of thirteen archers, moving up in draw weight changes the elbow and trunk of the women and barely touches the men.
- Contested After the release French elite archers moved more than intermediate ones, but in another study the sideways shift was the same at both levels.
- Contested In sixteen world-class archers the arrow left the string about 15 thousandths after the release began; a 1987 measurement on one archer gives twice that.
- Contested In a thesis on 63 British coaches the internet served mainly to look up what they already knew, but the most experienced also used it to learn.
- Contested In one national team years of practice follow the official grade, but in two other samples they separate neither the level nor the accuracy of the arrows.
- Contested Experts draw faster than beginners, but among archers who are already competent the length of the draw does not separate the best from the rest.
- Contested Experts react to the clicker faster than beginners, but among archers who are already strong the gap disappears, and on consistency the data are split.
- Contested In the only direct comparison half of the balance and movement measures are the same in recurve and compound, and the other half are not.
- Contested In a single study of archers the score varied by 3% between two sessions, far less than muscle activity, but strength showed higher consistency.
- Contested Over 576 arrows the total time of the shot does not predict score, but the length of the draw and of the release seems to matter a little in two small studies.
- Contested In archers the drawing-arm triceps is the most active muscle in one study and among the least used in two others.
- Contested While aiming, elite archers use their fingers, arms and trunk less, but the trapezius holding the shoulder blade works harder: the economy is not universal.
- Contested In four archers the drawing arm worked at around 80 per cent of maximum and switched off at the release, but in 1987 the deltoid came back on.
- Contested Over the whole aim two small studies see the body sway across the target; close to the release three larger studies see it sway towards the target.
- Contested Among beginners shooting without a sight, cross-dominance costs points; among trained archers the share of cross-dominant archers does not change with level.
- Contested Children starting a course sway eight times more in the shooting stance.
- Contested In one experienced archer the draw took 1.2 seconds and the aim 1.6, but studies with more archers find longer aims, between 2 and 6 seconds with the recurve.
- Contested The more recent studies tie a stiller bow to better scores, but null results are not rare and each study measures stability in a different way.
- Contested Between archers of different levels a quieter forearm goes with higher scores, but the studies on arrows of the same archer do not agree.
- Contested The two studies comparing one eye closed with both eyes open contradict each other: the first, with no tests, finds tighter groups, the second no difference.
- Contested In five elite archers the drawing side dominates in many muscles but not all; in nine recreational archers the two sides work at similar levels.
- Contested Two studies of archers, at 18 and 70 metres, find the finger flexors less active in one and more active in the other on the better arrows.
- Contested In eight elite archers, on the better arrows the finger extensor of the bow hand works less but the finger flexor works more.
- Contested In the better archers the shoulder muscles stay on after the release.
- Contested Studies linking aiming time to where the arrow lands point different ways, and within an archer the link changes from person to person.
- Contested Two small studies of archers disagree: in one a slower shoulder after release goes with the better shots, in the other a shorter final phase does.
- Contested A few small studies: in thirteen archers some shoulder angles differ between men and women, while in other samples the difference does not appear.
- Contradicted The only sound study of archers finds the aim lasting more than twice as long as the draw; the one finding them almost equal is in a questionable journal.
- Contradicted In a pilot on 4 traditional archers the best grip was never the one the rule assigns to height.
- Contradicted In nine elite women archers draw length without a clicker matched draw length with one, while the draw finished sooner and the aiming points grouped tighter.
- Contradicted With three fingers the force on the string is steadier, but only in a lab task without a bow; with a bow in hand, two-finger groups were no wider.
- Refuted Since 1990 every sample measured finds elite archers consistent with themselves and different from one another, in the lab and on competition video.
- Refuted To the eye, elite archers' fingers stay flexed, yet under the skin half of them open with the extensors and score no differently.