Pilates and balance in archers: Yoon 2012 study

The study puts archers in a group with tennis players, as athletes in unilateral sports that mainly load the upper body, and compares them with track and field athletes. There were forty-one in all, from a high school and a university in Daegu: ten archers and fifteen tennis players in the first group, sixteen track athletes in the second. All of them did eight weeks of Pilates, three times a week, two hours a day, with mat work, a foam roller and elastic tubing.

The pain reported at the start followed the areas each sport loads: shoulders, wrists, neck and lower back in the archery and tennis group, hips, knees and ankles in the track group. After the eight weeks pain fell almost everywhere in both groups, and the two clearest differences in favour of the archery and tennis group are the right shoulder, from 2.84 to 0.40 on a nought to ten scale against 1.84 to 1.36 in the track group, and the left wrist, from 1.36 to 0.48 against 0.34 to 0.20. The left hip is the exception: in the archery and tennis group reported pain rises from 1.40 to 2.00, while in the track group it falls from 2.83 to 0.40.

On the MFT S3-Check platform the indices, where a lower value means more stability, improved on three of the four measures in both groups: forward and backward stability from 5.13 to 3.40 in the archery and tennis group and from 4.93 to 4.14 in the track group, forward and backward sensorimotor control from 4.20 to 3.36 and from 4.23 to 3.59, left and right stability from 5.18 to 4.11 and from 4.74 to 4.07. The eight measures of body asymmetry taken with the three-dimensional scanner did not change significantly.

The athletes were already doing weight training, but none of them had practised Pilates in the previous six months. The work took place during the winter preparation period; tennis players and archers did their session in the afternoon and the track athletes in the morning.

The programme, reported exercise by exercise, falls into four blocks. Mat work in the first four weeks includes neck stretch, mermaid, side bend, curl up, supine knee twist, pelvic curl, bridge, hundred level one, single and double leg stretch, roll up and roll down, saw, swimming, spine stretch and rolling like a ball, eight repetitions for one set; from the fifth week the exercises become harder, with hundred level four, swan dive, teaser, shoulder bridge, side kick and push-ups, over two sets. The foam roller is used for releases and massage of the neck, thoracic spine, quadriceps and thigh, shoulder movements, arm circles and dying bugs; the tubing for leg lifts and circles, knee flexion and extension, arm circles and side leg pull.

There are four sets of measures. Body composition by bioimpedance with an InBody 3.0. Pain with a visual analogue scale questionnaire, region by region, before and after. Balance with the MFT S3-Check platform: the athlete stands on a round platform of 530 mm with a tilt range of minus twenty to plus twenty degrees, thirty seconds on the forward and backward axis and thirty on the left and right axis, and the system records stability and sensorimotor control. Body symmetry with an IBS-2000 three-dimensional laser scanner, which photographs the back at a height of 110 cm from a distance of 170 cm and returns the left to right differences in height and angle at the upper thoracic spine, the shoulder blade, the lumbar region and the buttocks. The analysis is a two-way repeated-measures analysis of variance, with the baseline value as a covariate where the groups started out different, and t tests in the follow-up comparisons.

The archers are never analysed on their own: they are ten inside a group of twenty-five, together with fifteen tennis players, and every published mean refers to the mixed group. No figure in this study describes an archer, and where the text discusses the left shoulder and wrist it offers the archery movement as a plausible explanation, not as separate data.

A group doing nothing is missing: both groups did Pilates, so the comparison the programme is set against is another sport, not the absence of a programme. Eight weeks of winter preparation, with the usual training load continuing, enter the result alongside the Pilates. The paper does not say whether the assessors knew which group each athlete belonged to, and there is no follow-up.

The ages do not agree: the abstract says sixteen to eighteen, while the table gives means of 18.47 and 17.80 years, so the sample includes university students. The description of the pain questionnaire, presented as a scale from nought to one marked at one centimetre intervals, does not match the values reported, which reach 3.42. And the conclusion goes beyond the data on one specific point: it says that Pilates improved body balance at the lower back and buttocks, while the three-dimensional scanner table shows no significant difference and the text, a few lines earlier, correctly calls it a tendency. The same applies to left and right sensorimotor control, described as improved on the basis of a follow-up comparison although the overall effect of time is not significant. The study measures nothing about shooting, neither score nor accuracy, and the text is in Korean with the abstract and tables in English.

The useful part for an archer is the map of the pain, not the programme. In a group of twenty-five athletes from unilateral sports, archers among them, the sore points sat where that kind of movement loads: shoulders, wrist, neck, lower back, and in the right shoulder the mean starting value was almost three out of ten. After eight weeks of Pilates those values fell, and in the right shoulder and the left wrist they fell more than in the track athletes.

What cannot be drawn from this is how much of that fall belongs to the Pilates, since the other group did it too and nobody was left without a programme, or how much belongs to the archers, since their data is mixed in with the tennis players'. The study does not touch scores, and the body symmetry measures, the very thing the conclusion declares improved, in fact did not move significantly. In the registry the source counts as indirect evidence on a mixed population.