With a heavier draw weight the trunk, shoulder and elbow angles change during the shot

The summary today

Everything we know comes from a single group of thirteen university students, seven men and six women, including four experts, four intermediates and five beginners, measured with inertial sensors while shooting five arrows per combination with 20, 25 and 32-pound bows, and reported in three papers. In the women something changes: moving from 25 to 32 pounds the bow-arm elbow goes from slight flexion to extension, from +7 and +4 degrees to about -9 (p = 0.046 and 0.034), and the trunk arches back more than twice as far, from about -8 to -17 degrees, while in the men it stays between -1 and -5. In the men, by contrast, none of the comparisons between the three bows comes out significant, and for everyone the drawing elbow sits at around 157 degrees whatever the bow, while flexion-extension and rotation of the bow shoulder separate neither the sexes nor the draw weights. The bows were tried in the same session and always from lightest to heaviest, so draw weight, order and fatigue cannot be pulled apart, and with six or seven people per group a null result does not rule out an effect. The only sample points two ways depending on sex: contested.

Also phrased as: "moving up in draw weight"; "overbowed"; "draw weight and posture"; "leaning back with a heavy bow"; "raised shoulder from too much draw weight"

Evidence

• 2024
  For Archers Published later

  13 university recurve archers, 6 women and 7 men of mixed experience, 25 and 32-pound bows at 10 and 15 yards, 5 arrows per combination, inertial sensors: trunk flexion-extension in the women goes from -7.17 and -8.29 degrees with 25 pounds to -17.02 and -17.47 with 32, in the men from -4.28 and -1.46 to -5.24 and -4.58; with the 32-pound bow the difference between the sexes is clear (p = 0.001 and 0.0002). Negative values mean the trunk arched back.

  An Ergonomics Analysis of Archers through Motion Tracking to Prevent Injuries and Improve Performance · Xiaoxu Ji, Jenna Miller, Xin Gao, Zainab Al Tamimi, Irati Arzalluz, Davide Piovesan

• 2024
  For Archers Published later

  In the same study, comparing 25 and 32 pounds in the women, the bow-arm elbow goes from +6.95 and +4.19 degrees to -8.86 and -8.66, that is from slight flexion to extension (p = 0.046 at 10 yards and 0.034 at 15), and flexion-extension of the bow shoulder also changes at 15 yards (p = 0.049); in the men the elbow goes from -3.17 and -1.34 to -2.49 and -4.43.

  An Ergonomics Analysis of Archers through Motion Tracking to Prevent Injuries and Improve Performance · Xiaoxu Ji, Jenna Miller, Xin Gao, Zainab Al Tamimi, Irati Arzalluz, Davide Piovesan

• 2024
  Against Archers Published later

  In the same study the men do not change their set-up between 25 and 32 pounds: the bow-arm elbow stays slightly extended with both bows (from -3.17 and -1.34 to -2.49 and -4.43 degrees), the trunk between -1.46 and -5.24, and significant differences between bows are reported for the women only. For half the sample draw weight does not move the angles.

  An Ergonomics Analysis of Archers through Motion Tracking to Prevent Injuries and Improve Performance · Xiaoxu Ji, Jenna Miller, Xin Gao, Zainab Al Tamimi, Irati Arzalluz, Davide Piovesan

• 2024
  Context Archers Published later

  Also in the same study, with the 32-pound bow bow-elbow flexion-extension is linked to that of the trunk (r = 0.44), and shooting at 10 or 15 yards changes neither posture nor the estimated lumbar load (L4/L5 compression in the women 558 against 531 N with 25 pounds and 576 against 552 N with 32). What moves the set-up is the bow, not the distance.

  An Ergonomics Analysis of Archers through Motion Tracking to Prevent Injuries and Improve Performance · Xiaoxu Ji, Jenna Miller, Xin Gao, Zainab Al Tamimi, Irati Arzalluz, Davide Piovesan

• 2024
  Context Archers Published later

  The same 13 archers with 20 and 25-pound bows and a low or high target: with 25 pounds the men abduct the bow shoulder more than the women (83.4 against 74.7 degrees, p = 0.04, and 84.4 against 75.8, p = 0.03), with 20 pounds there is no difference; the authors describe abduction rising in the men on the heavier bow and almost no change in the women. Same data as the other two papers, counts once.

  Exploring injury assessment using motion tracking technology and ergonomic tools in archery performance · Xiaoxu Ji, Irati Arzalluz, Xin Gao, Zainab Al Tamimi, Ethan Swierski, Davide Piovesan

• 2024
  Context Archers Published later

  In the same paper, with the 20-pound bow and the high target the women flex the drawing shoulder less than the men (33.8 against 46.7 degrees, p = 0.06), while with 25 pounds the values converge: according to the authors the extra force required of the women increases the flexion.

  Exploring injury assessment using motion tracking technology and ergonomic tools in archery performance · Xiaoxu Ji, Irati Arzalluz, Xin Gao, Zainab Al Tamimi, Ethan Swierski, Davide Piovesan

• 2025
  For Archers Published later

  The same 13 archers (7 men, 6 women; 4 experts, 4 intermediates, 5 beginners) with 20, 25 and 32-pound bows at 10 and 15 yards, always from lightest to heaviest: in the women the bow-arm elbow differs between bows, 20 against 32 pounds p = 0.04 and 25 against 32 p = 0.04 at 10 yards, 25 against 32 p = 0.02 at 15 yards (20 against 32 at 15 yards p = 0.19). It is the only angle that changes between bows.

  The Impact of Draw Weight on Archers’ Posture and Injury Risk Through Motion Capture Analysis · Xiaoxu Ji, Zainab Al Tamimi, Xin Gao, Davide Piovesan

• 2025
  Against Archers Published later

  In the same study, in the men no comparison between the three bows comes out significant, and the drawing elbow at release sits between 156.5 and 159.5 degrees in the women and between 156.7 and 157.5 in the men, across all six combinations of bow and distance. For half the sample, and for everyone's drawing elbow, draw weight does not change the set-up.

  The Impact of Draw Weight on Archers’ Posture and Injury Risk Through Motion Capture Analysis · Xiaoxu Ji, Zainab Al Tamimi, Xin Gao, Davide Piovesan

• 2025
  Against Archers Published later

  Also in the same study, flexion-extension and rotation of the bow shoulder separate neither the sexes nor the three draw weights, although in the women with 32 pounds these two angles vary by more than 20 degrees. The significant differences between the sexes lie elsewhere, between 9 and 15 degrees, in the drawing shoulder with 32 pounds and in bow-shoulder abduction with 25.

  The Impact of Draw Weight on Archers’ Posture and Injury Risk Through Motion Capture Analysis · Xiaoxu Ji, Zainab Al Tamimi, Xin Gao, Davide Piovesan

• 2026
  Context Review Published later

  Systematic review of five studies on the draw force line, in a journal with questionable editorial practices: it takes up the 2025 study of the 13 archers and summarises it as significant differences in trunk, shoulder and elbow at higher draw weights, with more consistent angles in the men and more variable ones in the women. No new data.

  Impact of Kinematic Variables of the Draw Force Line on Performance in Recurve Archery: A Focused Systematic Literature Review Questionable venue · Namchan Norbu Bhutia, Atanu Ghosh, Snehunsu Adhikari, Awesh Khati

Status history

1. 2024 Contested The first measurements arrive in two papers on the same group of thirteen university students, six women and seven men of mixed experience. With 25 and 32-pound bows, moving to the heavier bow the women arch the trunk back far more than before, from about -8 to -17 degrees, and their bow-arm elbow goes from slight flexion to extension (p = 0.046 and 0.034); the men, on the other hand, stay between -1 and -5 degrees of trunk and keep the bow elbow slightly extended with both bows, and differences between bows are reported for the women only. With 20 and 25-pound bows differences between the sexes come and go: with the heavier bow the men abduct the bow shoulder about 10 degrees more than the women, while the difference in drawing-shoulder flexion seen with the light bow disappears. Shooting nearer or farther does not change posture. The sample therefore already points two ways, with the set-up changing in the women and not in the men, and it counts once on each side: contested, on thirteen people who tried the two bows in the same session.
2. 2025 Contested The third paper on the same thirteen archers puts the three bows together, 20, 25 and 32 pounds, and also says where the change is absent. In the women the bow-arm elbow differs between bows (p between 0.02 and 0.04 in three comparisons out of four), but in the men no comparison between bows comes out significant; the drawing elbow stays between 156.5 and 159.5 degrees in every combination, and flexion-extension and rotation of the bow shoulder separate neither the sexes nor the draw weights. The split seen in 2024 holds with three bows, an effect in one sex and none in the other, and the same sample still counts once on each side: the status stays contested. The bows were always tried from lightest to heaviest, so order and fatigue add to draw weight.
3. 2026 Contested A systematic review in a journal with questionable editorial practices takes up the 2025 study without adding any data, and summarises it as more consistent angles in men as draw weight rises. A questionable venue does not decide a status, and there is no second sample: contested.

Related

Related articles

• The bow shoulder: how it rotates, why it rises and how hard it worksHow to hold the bow shoulder at full draw, why it tends to rise, and what X-rays, electromyography and position-sense tests have measured in archers.
• The archer's back: how much draw weight loads it and what the asymmetry of shooting leaves behindHow much a 20 to 32 pound bow loads the lower back, why trunk and body mass matter, and what the studies say about asymmetry in archers' bodies.
• What draw weight to choose: how to find it and when to change itWhat draw weight to choose and when to change it: marked versus actual poundage, how much strength to use, three criteria, young archers and each division.

Research lines

• 25 studiesArchery injuries: what research has measured since 1971
• 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