Aim 1 of my dissertation was to determine the effects of running-specific prosthesis (RSP) mass on the running economy of long distance runners with a transtibial (below-knee) amputation. To accomplish this, runners with a transtibial amputation ran with 100 g or 300 g added to their RSP while I measured metabolic power. I found that metabolic power increased by 0.9% for every 100 g added to the RSP, suggesting that decreases in RSP mass would reduce metabolic power and likely improve long distance running performance.

Aim 2 of my dissertation was to identify the biomechanical limitations of sprinting on the flat curves of regulation 200 m and 400 m tracks. To accomplish this, athletes performed a series of maximum effort sprints on a straightaway and curves while I measured lower body kinematics, kinetics, and ground reaction forces. I found that the inside and outside leg have distinct biomechanical functions during curve sprinting and the orientation of the hips, knees, and ankles affect force production and maximum velocity. These findings highlight opportunities for athletes to improve their sprinting performance.

Aim 3 of my dissertation was to monitor a runner’s injury risk with wearable devices. To accomplish this, I first developed a statistical model that uses data from an accelerometer clipped on the back of an athlete’s running shorts to accurately predict biomechanical variables associated with the magnitude and duration of external forces applied to the body during level ground running. Next, I developed a neural network capable of predicting a runner’s ground reaction forces across a range of speeds and slopes in near-real time. This approach was up to 2x more accurate than current state-of-the-art methods. These findings represent a substantial step towards using wearable technology to accurately monitor a runner’s injury risk and provide biomechanical feedback during an outdoor run.

Overall, my dissertation identified physiological factors that limit long distance running performance and biomechanical factors that limit sprinting performance, and developed methods to accurately monitor a runner’s injury risk with wearable devices.