If athletes are allowed to compete only with whatever they were born with there will be no Michael Phelps, Tiger Woods, Joe Montana, and your favorite sport star. The ethical question is not whether an athlete can enhance his or her ability artificially, it is whether the enhancement is available and adopted by the public, or their fellow competitors.
Tiger Woods had refractory surgeries, state-of-the-arts equipment, world’s finest training staff, and various machinery that tune his every muscles. Michael Phelp wore this magical suit to make him faster than fish. Joe Montana had back surgeries that actually made him stronger. Were they enhanced artificially? Sure they were, only within the admissible bounds.
Amy Mullins, pictured above, wants to compete with her carbon-fiber legs, so did Oscar Pistorius, below on the right, and several others. If those prosthetic legs gave them unfair advantage, what happens if they grew new legs through miraculous use of stem cells?
Technically, if we can grow limbs back, there was no alternation, only rejuvenation. But if such technology exists, there will be no more career-ending injuries, athletes will than take much higher risk pushing themselves. Would that be fair?