Today's performance-enhancing drugs take years to severely damage an athlete's health. Back in 1904, they didn't have time for such things. A couple of strychnine injections during the marathon at the 1904 Olympics helped Thomas Hicks nearly kill himself by the end of the race. It also helped him win a gold medal.
Today, you're most likely to find strychnine in rat poison — although some people don't use it because it's too cruel. You can also find it in ghoulish detective stories. Strychnine leads to convulsions, especially of the back, legs, and face. The muscles in the face pull taught, forcing the victims to smile as they die — generally of suffocation, since strychnine shuts off the ability to breathe. Strychnine does not cross the blood-brain barrier, which means that the victim is conscious until their death. It is an awful, awful way to go.
Which makes it odd that people injected it, or ingested it, well into the 20th century. Then again, you can't argue with results: one scientist in 1917 did notice that rats injected with strychnine navigated mazes faster, but by that time people had already been using it as a pick-me-up for three-quarters of a century. People took it as they would a stronger version of coffee. This makes sense, because strychnine and coffee share some odd habits. Both bind to the glycine receptor, although coffee binds to the adenosine receptor as well. Strychnine doesn't entirely block the receptor and paralyze the nerve — in fact, quite the opposite. Neurotransmitters — the chemicals that bind to the neuron and get it to fire — occur at different levels. Strychnine allows the neuron to fire, and pass signals along, even when neurotransmitter levels are low. It's sort of a hair-trigger for the body.
We see the effects of this in people who are suffering from strychnine poisoning. Convulsions can be set off by noise, light, touch, or other stimuli. To keep people from suffering too much, they are kept in quiet environments. People who have consumed strychnine as a performance-enhancer feel the urge to move around at a lower level of stimulus. Researchers who have self-administered strychnine have written about how restless they feel, and how much they suddenly need to get up and walk around after their doses. (In one case the researcher realized he had overdosed and desperately tried to save himself with other drugs while suffering from strychnine poisoning.) Dosing with strychnine means that a minimum amount of stimulus can keep the body going. That's very useful for long days and endurance races. The problem, once the drug is administered, is getting the body to stop again.
Image: Armin Kübelbeck