Natural forefoot-striking women (n=19) had lower patellofemoral contact force (4.3 vs 5.1 body weights) and stress (11.1 vs 13.0 MPa) and a lower knee frontal-plane moment than matched rearfoot strikers (n=19) at 4 m/s, but a higher ankle plantarflexor moment (3.12 vs 2.54 N·m/kg) and Achilles tendon force (6.3 vs 5.1 body weights)
Nineteen female athletes with a natural forefoot strike and 19 pair-matched women with a rearfoot strike underwent 3-D running analysis at 4 m/s; joint angles and moments, patellofemoral contact force and stress, and Achilles tendon forces were compared.
Participants
n=38 women: 19 natural FFS and 19 pair-matched RFS.
Protocol
3-D running analysis at 4 m/s in each runner's habitual pattern.
Key Results
Patellofemoral contact force 4.3 ± 1.2 vs 5.1 ± 1.1 body weight (P = 0.029) and stress 11.1 ± 2.9 vs 13.0 ± 2.8 MPa (P = 0.04), lower in FFS.
Knee frontal-plane moment lower in FFS: 1.49 ± 0.51 vs 1.97 ± 0.66 N·m/kg (P = 0.015).
Ankle plantarflexor moment higher in FFS: 3.12 ± 0.40 vs 2.54 ± 0.37 N·m/kg (P = 0.001).
Achilles tendon force higher in FFS: 6.3 ± 0.8 vs 5.1 ± 1.3 body weight (P = 0.002).
Authors' conclusion: lower knee load in FFS may reduce knee-injury risk; higher plantarflexor and Achilles load may raise ankle and foot injury risk.
Practical Application
Habitual forefoot-striking women carried less patellofemoral load and more Achilles load than matched rearfoot strikers: in these women, patellofemoral stress was 11.1 vs 13.0 MPa and Achilles force 6.3 vs 5.1 body weights against rearfoot strikers.
Inference: an athlete with patellofemoral pain and a history of Achilles trouble does not have a clean answer in strike pattern; the risk moves rather than disappears.
Not from this paper; the base's own practice: a cadence increase REF-620 lowers knee load without the full shift to the ankle.
Limitations
Women only; training level not specified in the abstract.
Habitual patterns only, between groups; no imposed switch, so the cause of the differences is not isolated.
Loading estimates at one speed (4 m/s); no injury outcome.
How this entry was checked and changed
Why this level
pair-matched cross-sectional lab comparison; habitual patterns only