By Jordana Bieze Foster
Chronic ankle instability (CAI) is associated with altered vertical ground reaction forces (vGRF) and loading rates during running, which may be related to altered landing patterns designed to protect the ankle joint, according to research from Indiana University in Bloomington.
Investigators assessed kinetics in 13 healthy young adults (six women) and 11 with self-reported CAI (six women), all of whom were experienced runners, as they ran on a treadmill at 3.3 m/s for five minutes.
Compared with the uninjured group, the CAI group had significantly higher impact peak forces and active peak forces, faster loading rate, and a shorter time to reach active peak force. Time to reach impact peak force did not differ significantly between groups. The findings were epublished in early November by the Journal of Athletic Training.
Although the study did not assess kinematics, the altered kinetic variables in the CAI group are consistent with previous findings that individuals with CAI run with a stiffer landing strategy than uninjured controls, possibly to protect the ankle.
Bigouette J, Simon J, Liu K, Docherty CL. Altered vertical ground reaction forces in participants with chronic ankle instability while running. J Athl Train 2016 Nov 4. [Epub ahead of print]