The competitive nature of sport encourages some participants to attempt to enhance their performance through the use of medicines, or through other means such as increasing the volume of blood in their bodies through artificial means.
体育运动的竞争性质使得一些参与者试图通过使用药物或者其他方法（如运用人工手段提高身体内的血液量）试图提高自己的竞技表现。