 Discussion continues about the relative advantage or disadvantage of using the blades.Researchers and analysts also point out that the research studies are done on level, stationary treadmills, and do not measure performance from starting blocks or on actual curved tracks.They also do not take into account differences in physiology between amputees and non-amputees, who have such factors as musculature, blade height and weight and differences in blood circulation patterns due to the history of their limb loss.