Instability training and balance in archery: Gao 2025

A systematic review of twenty studies on instability resistance training and balance in athletes, covering 664 participants in all (459 male, 157 female, 48 with sex not reported). Of those twenty studies only one involves archers.

The search across five databases returned 285 records, 278 after duplicates, 215 read in full and 20 included. Methodological quality, rated on the PEDro scale, runs from 4 to 7 points out of 11. Eleven studies find an improvement in static balance, nine in dynamic balance and three in reciprocal balance; four find no improvement in static balance. The equipment used is mostly wobble boards (8 studies), Swiss balls (6) and BOSU (6), then suspension systems, elastic bands, cushions, sand surfaces and trampolines. Duration ranges from 4 to 8 weeks, with ten studies at eight weeks, and frequency from two to five times a week.

The archery study is Prasetyo and colleagues, 2023: twelve athletes aged 14 to 17, suspension training on a BOSU, 18 circuit sessions, no control group, and a single outcome reported in the review, an improvement in single-leg standing time on the stork stand test. Duration in weeks and frequency are not stated, and that study's PEDro score is 4, the lowest in the set along with two others.

None of the twenty studies measures a shooting score: the review deals only with balance tests. There is no meta-analysis, the results are summarised in prose and no pooled effect exists.

A review registered on INPLASY and conducted following the PRISMA guidance. The databases searched were Web of Science, EBSCOhost with SPORTDiscus, PubMed, Scopus and Google Scholar, up to the end of 2023, with keywords combining the names for unstable surface training, the types of balance, and the terms for athlete and player. Duplicates were removed in EndNote, then two rounds of screening, on title and abstract and on full text, and finally agreement among all the authors on which papers to keep.

The inclusion criteria follow the PICOS scheme: healthy athletes or players with no distinction of age or sex; unstable surface training, alone or combined with other work, for not less than four weeks; comparison within a group or between groups; an outcome concerning balance; a single-group design or a randomised controlled trial.

Quality was rated on the PEDro scale, eleven items worth one point each, which the authors read as poor from 0 to 3, moderate at 4 and 5, high from 6 to 10. Balance was classified into three types, reciprocal, static and dynamic, and the results of the twenty studies were gathered under those three headings. The tests used across the studies include single-leg standing with eyes open and closed, the stork stand test, bipedal stance, the Y balance test, the star excursion balance test, single-leg side hops, the four-step square test and a force platform. No pooled effects or confidence intervals were calculated.

For archery the review rests on a single study, and of that study it reports one line: twelve adolescent archers, no control group, 18 sessions, one single-leg standing outcome. Duration in weeks and frequency are not stated, which among other things sits badly with the inclusion criterion requiring at least four weeks. The table records that study as having no control group, yet the text lists it among the works with between-group differences: the two statements do not go together.

Two other passages do not agree with themselves. Negra and colleagues, 2017, appears both among the studies showing a significant improvement on the stork stand test and among the two showing none. The abstract gives PEDro scores from 4 to 8, while the table tops out at 7, and a study with 6 points is labelled moderate when the scale the authors describe calls 6 to 10 high.

The quality appraisal shows one fact the review does not comment on: in all twenty studies the PEDro items on concealed allocation and on blinding of participants, therapists and assessors score zero. The authors acknowledge in turn that between 80% and 90% of the interventions combined unstable surface work with other kinds of training, so the effect of instability cannot be separated out, and that an analysis accounting for differences between sports is missing.

The point that matters most for this registry remains: none of the twenty studies measures score, arrow grouping or any other shooting outcome. Everything the review states concerns balance tests on a platform, on one leg or in reaching positions.

The review is often used as general support for the idea that unstable surface work is useful to archers. Read in full it says less than that: out of twenty studies, the only one on archery has twelve adolescent participants, no comparison group, and single-leg standing time as its outcome. Standing on one leg for longer is not a score, and the review contains no shooting data at all.

What an archer takes away is a frame rather than a finding: across eleven different sports, with boards, balls and cushions, four to eight weeks of work is usually enough to improve balance tests, and in four studies out of twenty it does not improve them. Among archers the same effect has not been measured under controlled conditions.

Nothing here tells you how much unstable surface work to do, or when, or whether it takes time away from something else. In the registry this source serves to frame the line on balance and stability, and to show how thin the part of that literature concerning archers actually is.