Choppin suggested that the lower ground force was probably due to the relative lack of muscle in an amputee 's leg .
肖邦认为，较低的蹬地力量可能是因为截肢者的腿部肌肉相对缺乏所致。
Simon choppin , a sports engineer at sheffield hallam university , said the pistorius controversy rested on whether his prosthetics increased the efficiency of his limbs , allowing him to achieve higher speeds for less effort .
