A meta-synthesis of the paper “Thinking about your running movement makes you less efficient: attentional focus effects on running economy and kinematics” - Schücker, L. & Parrington, L. (2019).

Abstract

Meta-Student is a collaborative research platform, coordinated by the Sports Science Replication Centre, that pools independently collected undergraduate research datasets into statistically powerful individual-participant-data (IPD) meta-analyses. Students at multiple institutions each run a small, standardised study under local ethical approval and supervision and upload anonymised participant-level data; the platform combines these contributions in a single pre-specified statistical model and grows the pooled sample sequentially until the evidence reaches a pre-specified stopping criteria. Every contributor whose data pass quality validation is a named co-author, and each completed study yields an openly-archived dataset and a reproducible completion report. We convert otherwise-unpublished, individually underpowered/imprecise student projects into cumulative, adequately powered/precise evidence. One avenue of study design is replication, in line with our vision at the Sports Science Replication Centre (www.ssreplicationcentre.com). Candidate studies for replication are selected systematically rather than by nomination, using a Replication Research Identification System (RRIS). RRIS scans applied sport-and-exercise-science research across 18 quartile-1 journals and ranks experimental and quasi-experimental studies by a modified Replication Value index — a time-adjusted form of Isager et al.'s (2023) framework that combines a study's uncertainty (small sample size, 1/N) with its impact, where impact is operationalised as relative citations (citations per year) rather than total citations, so that recently-published findings are not disadvantaged for having had less time to accrue citations. Studies with a high Replication Value (influential claims resting on small, uncertain samples) are the most efficient use of scarce replication resources and are prioritised as potential Meta-Student targets, subject to feasibility screening for the platform's supported designs, and then expertise. The study preregistered here was selected through this process. Running economy (RE), in this case the oxygen cost of running at a fixed sub-maximal speed, is one of the more consistent physiological correlates of distance-running performance (Saunders et al., 2004a; Barnes & Kilding, 2015). A body of work led by Schücker and colleagues reports that where a runner directs their attention changes their RE: an internal focus (attending to one’s own movement or breathing) produces a higher oxygen cost than an external focus (attending to the environment). Schücker, Hagemann, Strauss, and Völker (2009) is the original publication of this effect and was recently replicated in 2019 by the same authors, which is the study under focus here (Schücker & Parrington, 2019). In n = 12 runners performing three counterbalanced 6-minute treadmill conditions (movement / breathing / video) at an individualised sub-maximal speed, VO₂ was significantly higher in both internal-focus conditions than in the external (video) condition (movement – video: +2.6%, d = 0.73; breathing – video: +4.2%, d = 0.77). Our main comparison of interest is the movement vs. video contrast and since we adapt some of the original methods, this should be considered a conceptual replication. Critically, the most recent robust-Bayesian re-analysis (McKay et al., 2024) concludes that the apparent external-focus superiority is substantially inflated by reporting and publication bias. We feel that this claim needs a multi-site replication for this reason. The under-powered original (recruited n=12, tested n=11) yields wide confidence intervals and the reported effects (d ≈ 0.73–0.77) may be vulnerable to inflation (Button et al., 2013). The supporting evidence is dominated by one research group and, largely, one laboratory and language (German instructions). Independent, multi-site, multi-language replication is the decisive test of whether the effect generalises or is a lab/context artefact. Pooling participant-level data (IPD) across many student laboratories does two things a single replication cannot: (i) it delivers the statistical power to estimate the effect precisely and to test it against a smallest-effect-size-of-interest (ii) it provides a severe, pre-registered test of the underlying theory with a real risk of falsification. The meta-synthesis is supported by the original author, Linda Schücker.