Excelling at sports takes a huge amount of determination, not to mention years of practice to master and co-ordinate the complex patterns of movements involved. Faced with stiff competition and the pressure to win, some professional athletes resort to doping to enhance their performance, but—as the recent furor over cyclist Lance Armstrong shows—this goes against the sporting ethos and is severely frowned upon.
Doping usually refers to the use of performance-enhancing drugs. After years of denial, Armstrong finally admitted using three drugs to help him win the Tour de France seven times: erythropoietin (EPO), a naturally-occurring hormone that stimulates the production of red blood cells; testosterone, another natural hormone that increases muscle mass, among other effects; and corticosteroids, man-made hormones that reduce inflammation.
Some neuroscientists now suggest that two methods of brain stimulation might enhance sporting performance, too. The non-invasive techniques are already widely used to modulate brain activity: transcranial magnetic stimulation (TMS), in which a doctor uses a figure-eight-shaped coil near the scalp to apply magnetic pulses to a specific region of the brain, and transcranial direct current stimulation (tDCS), in which small electrical currents are applied to the brain via electrodes placed on the scalp. [See: Transcranial Magnetic Stimulation: From Tool to Treatment]
TMS and tDCS are now used by both basic researchers and clinicians. Both techniques can either enhance or inhibit the activity of specific brain regions, depending on the intensity and frequency of stimulation; they have become a valuable tool for researchers investigating how different parts of the brain contribute to behaviors and thought processes. In the clinic, they are used to help doctors diagnose neurological disorders, and monitor and facilitate a person's rehabilitation following stroke.
“There are two ways that brain stimulation could possibly improve sporting performance,” says neuroscientist Nick Davis of Bangor University in Wales, author of a recent opinion piece on the subject. “One is during or just before the performance. If you’re nervous, a little brain stimulation could damp down your muscle responses, a bit like beta-blockers. Another is during training, when it could help you to focus.”
There is as yet no research that directly examines the effects of brain stimulation on sporting performance, but many studies of stroke patients and healthy participants suggest that it could potentially be used to improve endurance and enhance learning of the motor skills involved.
In 2007, for example, a team of Italian researchers reported that tDCS of the motor cortex can increase endurance time for voluntary arm movements by more than 15%. Japanese researchers reported that it can also increase muscle force in the toes, fingers, and knees. Other studies show that TMS can shorten reaction times to visual, auditory and touch stimuli, reduce tremor, and enhance the acquisition of complex motor skills.
Researchers, including cognitive neuroscientist Vincent Walsh of University College London, remain skeptical of their application to sport, however. “Brain stimulation might make you better at something in the lab,” Walsh says, “but that’s under conditions where you’re pressing buttons in a dark room. You’re not under any pressure to win, and you don’t have memories of how badly you played in the past five minutes.”
“The gains seen in the lab are statistically significant, but they’re not necessarily behaviorally meaningful, and there’s absolutely no evidence that any of it translates to the real world.”
Walsh also points out that the apparatus used to apply brain stimulation is still not portable enough to be used in this way. “It’ll be very difficult to apply it when people are actually doing stuff,” he says “and it’s pretty unlikely that the effects would have a lasting effect in the rough and tumble of sport.” Even so, technological advances will inevitably result, at some point in the not-too-distant future, in wireless and wearable devices that enable brain stimulation to be applied in such situations.
This raises concerns over safety. The popularity of ‘do-it-yourself brain-hacking’ has also increased dramatically in recent years—brain stimulation kits made from cheap, off-the-shelf components are now commercially available, and hobbyists are even building their own kits and zapping themselves in an effort to enhance their mental abilities. It’s therefore possible that they will do the same to attempt to enhance their sporting performance, and that over-zealous parents could try using such kits on their children.
Davis acknowledges that his article and others like it will bring this potential use of brain stimulation technology to a wider audience, but urges caution. “Brain stimulation shouldn’t be taken lightly,” he says. “As a medical procedure it’s fine, but it’s not safe to do ‘in the wild,’ and there might be long-term effects that we still don’t know about.”
While steroids and other performance-enhancing drugs can be detected with blood tests, it is not possible to determine whether someone used brain stimulation during their sports training. Consequently, it would be extremely difficult to regulate the use of brain stimulation in sports.
Even if brain stimulation does prove to be effective in enhancing sporting performance, it would almost certainly be viewed by sporting associations as being no different from the use performance-enhancing drugs: a new, high-tech way of cheating. “It’s an interesting potential use of this technology, but it smacks of desperation,” says Walsh. “We don’t want a generation of kids thinking they need a bit of brain stimulation. It loses the essence of sport.”