Landing retraining cut impact force, not proven injuries

Non-contact anterior cruciate ligament injury is common and disabling, often requiring reconstruction and setting people up for early post-traumatic osteoarthritis, which makes scalable exercise-based prevention a genuine public health priority. One of the few risk factors athletes can actually change is how they land: excessive peak vertical ground reaction force during landing is treated as a modifiable biomechanical risk marker. Whether reducing that force actually lowers injury incidence, however, is explicitly unproven. This review asked a narrower and answerable question — does movement retraining reliably reduce peak landing force in pivot-sport athletes and in general athletic populations?

The authors searched MEDLINE via PubMed, Embase and the Cochrane Central Register of Controlled Trials from inception to 25 May 2026, with two reviewers independently screening records and extracting data. They pooled results using random-effects meta-analysis with the DerSimonian-Laird method and expressed effects as Hedges' g. Risk of bias in individual trials was assessed with RoB 2 and overall certainty of evidence with GRADE, and the protocol was pre-registered in PROSPERO. Nine comparisons drawn from eight randomised controlled trials, together including 292 participants, met the criteria. Subgroup analysis split pivot-sport athletes from general athletic populations, and knee flexion angle at initial contact was examined as a secondary biomechanical outcome.

Movement retraining significantly reduced peak vertical ground reaction force, with a pooled Hedges' g of -0.94 (95% CI -1.34 to -0.54), though heterogeneity was substantial at I2 = 63%. The effect was larger in general athletic populations (g = -1.50) than in pivot-sport athletes (g = -0.66), a subgroup difference that reached significance (p = 0.005) but rests on only three general-athletic comparisons. Knee flexion angle at initial contact showed a non-significant trend towards increasing (g = 0.48; p = 0.18). GRADE certainty was rated low. Most importantly, no included trial measured injury incidence at all.

This confirms that landing mechanics are trainable, which underpins the many neuromuscular warm-up programmes already used in sport. What it does not do is close the loop between the surrogate marker and the outcome anyone cares about, and the authors are unusually candid in labelling their findings hypothesis-generating. The counterintuitive subgroup result — bigger changes in general athletes than in the pivot-sport athletes at highest risk — could reflect ceiling effects in trained populations or simply the small number of comparisons. Trials powered for injury incidence, not force plates, remain the missing piece.

This is a reason to think that how you land is modifiable with structured coaching, and that measurable change can appear across a range of athletic populations. It is not evidence that landing drills will prevent an ACL tear, because none of the pooled trials counted injuries. The low certainty rating and wide variation between studies mean the size of the force reduction should be read loosely rather than as a precise number. If you follow injury-prevention programmes in sport, this adds mechanistic plausibility to what they do without proving the endpoint they promise.