Nobody seemed terribly surprised when two North Korean athletes tested positive for performance enhancing drugs at the Olympics last week. By now, stories of disgraced athletes sound familiar almost to the point of tedium. But if you had the patience to read beyond the headlines, you might have noticed something unusual about this particular scandal—namely, the nature of the banned drug the athletes were using. That drug was propranolol, and the athletes using it were pistol shooters. Propranolol is not exactly a cutting-edge performance enhancer. If you are familiar with propranolol, it is probably because you (or your parents) take it for high blood pressure. Its value as a performance enhancer comes from its ability to mask the effects of anxiety, such as the tremor that might cause one’s hand to shake when aiming a pistol. That propranolol can improve athletic performance is clear, and not just for pistol shooters. Whether it ought to be banned is a more complicated question.
Propranolol comes from a class of drugs known as beta blockers, which lower blood pressure by blocking particular sympathetic nervous system receptors. These receptors also happen to be the ones that get activated in times of fear or anxiety, which is why beta blockers are useful as performance enhancers. A beta blocker can keep a person’s hands from trembling, his heart from pounding, and his forehead from beading up with sweat. It can also keep his voice from quavering, which is why shy people sometimes sneak a beta blocker before giving a big speech or a public presentation. Beta blockers do not directly affect a person’s mental state; taking a beta blocker before firing a pistol is not like taking a Valium, or tossing back a shot of Jack Daniels, because beta blockers do not alleviate anxiety so much as block the outward signs of anxiety. A pistol shooter on beta blockers will still be nervous, but his nervousness will be less likely to make his hand tremble.
Beta blockers seem to be especially good performance enhancers when the performance in question involves an anxiety-producing public setting. This is because a large part of the anxiety of performing in public comes from the worry that one’s anxiety will become outwardly obvious. Most people who worry about public speaking, for example, aren't worried that they'll flub their lines, trip and fall as they approach the podium, or deliver an hour-long speech on television with their pants unzipped. They worry that their anxiety will become apparent to the audience. They're terrified that their hands will tremble, that their voices will become high-pitched and quivering, and that beads of sweat will appear on their foreheads and upper lip, like Richard Nixon trying to explain Watergate. This is why beta blockers are so useful; people who have taken a drug that blocks the outward effects of their anxiety become less anxious—not because the drug is affecting their brain, but because their worst fears are not being realized.
Beta blockers have been around since the 1960s, but it took a while before anyone noticed how useful they were for performance anxiety. Probably the first performers to start using them widely were musicians, especially classical musicians, whose hands can get clammy or tremble during a concert performance. In the mid-’70s, a team of British researchers tested the effects of a beta blocker on the performances of skilled violinists and other string musicians. They made sure that the musicians were playing under maximally stressful conditions by booking them in an impressive concert hall. They also invited the press to attend, and recorded all the sessions. The musicians were asked to perform four times each, twice on placebo and twice on beta blockers, and their performances were scored by professional judges. Not only did the musicians tremble less on the beta blocker, they also performed better. Usually the improvement was minimal, but for a handful of musicians it was dramatic.
From a competitive standpoint, this is what makes beta blockers so interesting : they seem to level the playing field for anxious and non-anxious performers, helping nervous performers much more than they help performers who are naturally relaxed. In the British study, for example, the musician who experienced the greatest benefit was the one with the worst nervous tremor. This player's score increased by a whopping 73%, whereas the musicians who were not nervous saw hardly any effect at all.