I personally think that if you are asking exceptionally much of your body, like showing your bike the french country side for two weeks, doing 200 km every day, or trying to ice speed skate faster than it is legal to drive your car through town, or regularly visit cities across the globe to try to be the first to cross some fictional line 42 km after crossing another fictional line, or keep squatting until you can lift a Volkswagen beetle, your body will need exceptionally much. Is it cheating? Is it unfair? Maybe, but I don't believe there is not a professional bicyclist that does not take performance enhancing substances. Do I care? Nope! Do I care if ultra long distance hikers use performance enhancing substances? Nope!