Rearfoot strikers have smaller resultant tibial accelerations at foot contact than non-rearfoot strikers

Purpose Overuse injuries are common in recreational runners. Recent reports have implicated the characteristics of the footstrike in the etiology of stress responses in the tibia. This has motivated efforts to modify the loading at footstrike by altering the orientation of the foot at first contact. The present study aimed to: 1) report typical magnitudes of resultant tibial acceleration (TA) in women distance runners; 2) contrast TA in rearfoot and non-rearfoot striking runners; and 3) examine TA during non-natural footstrike patterns in runners. Method We used a leg-mounted tri-axial acceleration monitoring unit to measure TA and angular velocities. Twenty injury-free women distance runners (age 27.8±3.7 years, height 168.1±6.2 cm, body mass 59.2±7.3 kg, weekly mileage >20) participated in the study. The sensor was positioned 5cm above the medial malleolus along the medial tibial border and tensioned to 22N with a Velcro strap. Multiple 60-second running trials at 3.13 m/s on a force-measuring treadmill (Kistler 9287 plate) were collected.