We measured block time (TBlock, time from first reaction to block clearance) and CoM velocity at block clearance (Vf, determined by integration of mass-normalized horizontal force curves with initial velocity equalling zero). Body mass (m) included the mass of the prosthetic parts in ASs. As the initial velocity (Vi) is zero in the set position of the sprint start, the formula for the calculation of average horizontal block power (P¯) can be simplified by omitting the Vi2 term: P¯=mVf22TBlock(2)