• Skip the Olympics (which has much stricter drug testing) in your prime for any dubious reason and you're on the list.
• Enjoy your best season in years in your late 30s, four or five years after your last "best season," and you're on the list.
• If you're a skinny dude who miraculously managed to add 20 pounds of muscle to your scarecrow frame, you're on the list.
• If you chopped down the recovery time of a debilitating injury to something that just didn't seem possible a year ago, you're on the list.
• If you were really good and really ripped at a really young age, and now your body is breaking down much sooner than it should be breaking down, you're on the list.
• If you're exhibiting a level of superhuman endurance that has little correlation to the endurance of any of your competitors, you're on the list.