Running at submaximal speeds, the role of the intact and prosthetic limbs for trans-tibial amputees

•The prosthetic limb brakes less rather than propels more at higher speeds.•The prosthetic limb vertical drive is reduced at higher speeds compared to control.•The intact limb brakes more at lower speeds.•No increased vertical loading on the intact limb compared to controls.•Braking and propelling peak force, step length and frequency associate with speed. Dynamic Elastic Response prostheses are designed to absorb and return strain energy in running. Past research has focused on running prostheses with a single toe spring designed for high speeds. To determine how runners with amputation modulate the ground reaction force of each limb to run at different speeds using a general-purpose dynamic prosthesis which has a heel spring. Overground running data were collected in 16 recreational runners (8 transtibial amputee using their own BladeXT prosthesis and 8 controls) using Vicon Nexus V.2.5 with Kistler force plates. Participants ran at self-selected running pace, 70% and 130% of that pace. Vertical, braking and propulsion peak ground reaction forces and impulses and vertical loading and decay rates were analysed between limbs at each speed (ANOVA) and their association with speed assessed (simple linear regression). The vertical, braking forces and impulses and propulsive force were significantly less (p