Effects of load carriage on biomechanical variables associated with tibial stress fractures in running.

•Heavy load carriage (≥ 11.3 kg) increased loading rate and absolute free moment.•Heavy load carriage also increased rearfoot eversion and stride frequency.•Load carriage of 4.5 kg did not alter variables associated with stress fracture.•Increases in stride frequency may help counteract increased demand of load carriage.