The prospective-prediction claim only. The underlying force measurement is graded separately at SSMT-2026-0007.
Verdict
ContradictedThe best available evidence points the other way.
Independent evidence found against the claim.
This claim is split. The prediction limb. Graded separately because the measurement limb is Partially supported and grading them together would let the false half ride on the true half.
The marketing performs a surrogate substitution: validity of a measurement is silently transferred to validity of a prognosis.
Evidence located
0
prospective in-shoe → injury studies
3
prospective asymmetry studies — all null or inverse
836
largest n
0.80
hazard ratio — protective direction
Findings
The decisive study. 836 recreational runners followed for six months with 107 injuries. Greater asymmetry was associated with lower injury risk — flight time HR 0.80 (95% CI 0.64–0.99), peak braking force HR 0.96 (0.93–0.98). The authors state plainly that gait asymmetry was not associated with higher injury risk.
Corroborated. In 210 novice runners, injured runners showed lower asymmetry, and no significant relationship survived adjustment; the authors noted observed differences may be a consequence rather than a cause of injury. A collegiate cross-country study (n=22) found no difference.
The largest wearable prospective study is null. 674 military cadets wearing an on-shoe accelerometer, 60-day follow-up, 75 injuries: no running biomechanical variable was associated with injury risk (all p>0.05). Only female sex (HR 1.89) and prior injury (HR 1.86) predicted injury.
Note the asymmetry in sample sizes. Validation cohorts are n≈11–30 in a lab. The prospective cohorts that actually test the marketed promise are n≈674–836, and they are negative.
The broader literature does not rescue it. Two systematic reviews of limb asymmetry and injury both conclude the findings are too inconsistent to support clinical thresholds. Where prospective asymmetry signals do exist, they come from different constructs in different populations — eccentric hamstring strength, Y-balance reach, single-leg hop distance — none of which is in-shoe load asymmetry during training.
What would change this verdict
A prospective cohort using the actual device in free-living training, with in-shoe-measured asymmetry as the baseline exposure and medically-confirmed time-loss injury as the endpoint, followed ≥6 months, n≥500, adjusted for prior injury, sex and training load — reporting a hazard ratio whose lower confidence bound is meaningfully above 1.0. Current best evidence gives hazard ratios below 1.0.
Practitioner read
No study has ever followed athletes wearing these insoles and shown that a lopsided reading predicted a future injury. When researchers tested the underlying idea in 836 runners over six months, the more asymmetric runners were if anything slightly less likely to get hurt. Use these as a load-monitoring or rehab-progress tool if you like, but do not let an asymmetry number drive a training restriction or a return-to-play decision.
Could not be verified
One systematic review's study counts (31 studies; 8 null / 10 partial / 10 significant) come from search-index summaries rather than full text (403). Re-verify before publication.
Listed rather than dropped. Counts are floors, not censuses.
Sources
Malisoux L, et al. (2024). BMJ Open Sport Exerc Med 10(1):e001787 — n=836 ↗
Weart AN, et al. (2025). Orthop J Sports Med 13(2) — n=674 cadets ↗
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