Trunk and balance in para archers: Arkin 2021

The study compares 10 Turkish archers with a physical disability and 10 able-bodied archers, all scoring between 550 and 720 on a World Archery round, on a set of measures of the shoulder, trunk, seated balance, body perception and quality of life. The able-bodied archers reached further in all four seated reach tests: 39.30 against 27.10 forwards with one arm, 42.00 against 22.40 with both arms, 20.70 against 13.30 to the right and 19.90 against 13.60 to the left. They also had more internal rotation at the right shoulder (78.50 against 52.00 degrees) and more horizontal adduction at the left (124.00 against 111.20), and higher SF-36 scores for physical functioning (95.00 against 29.50) and for role limitations due to physical health (95.00 against 75.00).

The group with a disability, on the other hand, had larger arm circumferences, 34.50 against 30.65 cm on the right and 34.60 against 30.50 on the left. Trunk endurance, manual strength at the shoulder and elbow, and the body perception scale (162.90 against 155.20) showed no significant differences. Strength, however, was graded 5 out of 5 in all twenty archers, so the test could not separate anyone. In the static trunk extension hold the able-bodied group averaged 86.40 against 57.92, a large difference that with ten people per group and wide variability is not significant (p = 0.149).

The 20 archers, 10 women and 10 men aged 18 to 55, came from the Turkish federation for physically disabled sports and from the Turkish Archery Federation; all held the bow in the left hand and had been shooting for at least a year. For the archers with a disability the paper refers to the seated classes, linked to tetraplegia and paraplegia; exclusions included spinal cord injury at C5 or above, upper-limb spasticity and shoulder pain in the previous six months. Each archer's type of disability and their division, recurve or compound, are not reported.

Everything was measured once, during the season: arm and forearm lengths and circumferences with a tape measure, shoulder range of motion (the instrument is not given), the strength of eight shoulder and elbow muscles with the 0 to 5 manual muscle test, and trunk endurance by counting repeated flexions and extensions and timing how long a position was held. Balance was assessed seated with three reach tests, forwards with one arm, forwards with both and sideways, read off a tape fixed to the wall at shoulder height; the table gives no units, presumably centimetres. The Body Perception Scale (40 to 200 points) and the SF-36 questionnaire complete the picture. Groups were compared with independent-samples t tests.

With ten people per group and a single measurement, the study is a snapshot of two groups that differ in many ways besides disability; it says nothing about the effect of archery on the trunk or on balance, although the authors read it that way in their discussion. They themselves note the lack of a before-and-after comparison and of a control group.

The text and tables do not always agree. In the results arm circumference is said to favour the able-bodied group, while the table and the abstract give it to the group with a disability. The text names physical functioning and emotional role limitations as the significant SF-36 subscales, but in the table emotional role limitations have p = 1.000 and the significant one is physical role. The discussion describes significantly greater external rotation in the disabled archers, which the table does not show (p = 0.391 and 0.227). The difference in competition score, 629.50 against 577.40, is reported as not significant with p = 0.551: with the standard deviations given, a comparison between the groups yields a much smaller value, so the two groups probably also differed in shooting level. Arm and forearm lengths are identical to the decimal between right and left in both groups, which suggests a transcription error.

The reach tests were designed for people with impaired trunk control: that able-bodied archers reach further was to be expected, and it says nothing about the kind of balance shooting requires. The manual strength test gave everyone the top grade, so it cannot detect differences between trained archers.

For archers the study changes little. It describes archers who shoot seated, with lower mean competition scores (577 against 629) and no significant differences from able-bodied archers in trunk endurance, at least on the simple tests used here, or in body image, while reaching less far in seated reach tests and reporting lower physical quality of life, as might be expected in people with paraplegia or tetraplegia. The larger arms in the group with a disability may reflect daily use of the upper limbs rather than archery; the authors make this argument for shoulder mobility, not for arm circumference.

The reduced internal rotation of the right shoulder, the drawing side, in archers with a disability is something the authors also find in another study, but here it is not linked to pain or to score. The idea that archery improves trunk stability in people with a disability remains the authors' hypothesis: the study did not follow anyone over time. For a coach working with wheelchair archers the paper is mainly a baseline description, with numbers to be read cautiously given the inconsistencies between text and tables.