Statistical Analysis This research is designed to determine the effects of prosthesis type on a variety of performance and injury-risk related outcome variables across a range of running speeds. A three factor (Group x Limb x Speed) mixed model ANOVA will be used to identify statistical changes of the following dependent variables: peak hip, knee, and ankle joint powers and mechanical work; average ground reaction forces; loading rates; and EMG amplitudes. Group (Individual Lower Extremity Amputation Running-Specific Prosthesis (ILEARSP) vs Individual Lower Extremity Amputation Traditional Prosthesis (ILEATrad) vs. Control) will be considered as a between-subjects independent variable, Limb (prosthetic/intact or left/right) as a within-subjects independent variable and Speed (2.5, 3.0, 3.5, 4.0, 5.0, and 6.0 m/s) as a within-subjects independent variable.