Bilateral practice in archery: Bund 2010 study

Forty right-handed beginners learned to shoot at a target 10 metres away, randomly split into four groups that used the two sides of the body differently. The first group shot half its practice arrows right-handed and half left-handed; the second shot 75% with the dominant side and 25% with the other; the third did the reverse, 25% dominant and 75% non-dominant; the fourth, the control group, shot only with the dominant side.

Measured on the dominant side, scores rose on average by about 15% from the pre-test to the two post-tests in the three groups that trained both sides, and by just under 8% in the group that used the dominant side only. The largest gain was in the half-and-half group, almost 20%, followed by the 75-25 group at 15%; the group shooting mostly with the non-dominant side averaged 9%, still more than the control group. Two weeks later the bilateral groups had held on to their improvement better. At the new distance of 15 metres those who had trained both sides gained 4% on their pre-test, while those who had used only the dominant side lost 9%.

The study, from the Institute of Sport Science at the University of Oldenburg, is reported in a two-page article in the Deutsche Schützenzeitung, the magazine of the German shooting federation. After a standard introduction to technique, each participant took a pre-test of three arrows with each side of the body, then three days of practice totalling 60 arrows, split between the two sides according to group. Then came a post-test ten minutes after the last session and another two weeks later, both at 10 metres, and two transfer tests at the same times at 15 metres. Every test consisted of three arrows per side, scored under the rules of the international federation, then FITA, as the total of one three-arrow end.

The article is a popular summary, not a peer-reviewed paper: it gives no group sizes, raw scores, standard deviations or statistical tests, and reports the results only as percentage improvements on the dominant side. With around ten people per group and a three-arrow test, a single arrow shifts the percentage a great deal, so differences of a few points between groups may be down to chance.

It does not say what bow was used, or how participants shot with the non-dominant side, whether with left-handed bows or with equipment suited to both sides. The participants were complete beginners with 60 practice arrows in all, and the authors themselves leave open whether the effect holds for more experienced archers.

For an experienced archer the study says nothing directly, since it concerns people shooting their first sixty arrows. For anyone teaching beginners it is an interesting finding: in the first few days, alternating arrows between the dominant and the other side did not slow learning on the dominant side, and was followed by a larger improvement and better adaptation to a new distance. The authors read this as the effect of bilateral practice already seen in other sports skills, and suggest that at least half the arrows should stay on the dominant side; that is their reading of the three groups, not a tested rule.

It remains a small experiment, briefly reported, with three arrows per test, on beginners who shot for three days. It does not say how long the advantage would last, or whether shooting with the non-dominant side makes sense once technique is established.