A-46 Free Communication/Poster - Running Biomechanics Wednesday, May 30, 2018, 7:30 AM - 12:30 PM Room: CC-Hall B
High vertical loadrates are a risk factor for running injuries. Overstriding is thought to increase loadrates, and is indicated by increased foot and tibial angles at footstrike. However, the relationship between landing alignment and loadrates has not been well established.
PURPOSE: To investigate the association between sagittal plane foot angle (FA) and tibial angle (TA) to vertical loadrates in both healthy and injured forefoot (FFS) and rearfoot strike (RFS) runners.
METHODS: This is an ongoing study with 52 healthy runners (35 RFS, 17 FFS) and 24 injured runners (14 RFS, 10 FFS) for a total of 76 runners (51 M, 25 F; age: 34.3±11.4 yrs). Vertical average loadrate (VALR) and vertical instantaneous loadrate (VILR) were obtained while running at 2.68 m/s on an instrumented treadmill. All runners reported 0/10 pain during the assessment. Sagittal plane FA and TA at footstrike were measured from video recording using an open-source program. Positive FA designated RFS. Positive TA defined as ankle anterior to knee. Correlation coefficients (r) were computed for FA and TA with VALR and VILR (p≤0.05; trend: p ≤0.10).
RESULTS: Healthy RFS - FA and TA were negatively correlated with VALR and VILR. Injured RFS - Trend toward negative correlation between TA and both VALR and VILR. Healthy FFS - TA was negatively correlated with both loadrates. Injured FFS - No significant correlations.
CONCLUSION: In contrast to current thought, preliminary results suggest that increasing FA and TA at footstrike are associated with decreasing vertical loadrates. This relationship was strongest for the FA of healthy RFS runners and weakest for the FA of both healthy and injured FFS runners.