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Researchers from the University of Kent have successfully demonstrated that it is possible to improve endurance through brain stimulation.
Brain Stimulation and Endurance
Dr. Lex Mauger and colleagues at Kent’s School of Sport and Exercise Sciences (SSES) wanted to determine to what extent fitness, or endurance, depends on both the mind and the body.
They did this by conducting a test in a group of 12 active participants where they had to cycle until failure, until they couldn’t continue [1]. In this placebo-controlled study, the brains were stimulated by a mild electrical current applied to the scalp (transcranial direct current stimulation or tDCS). This increased activity in an area of the brain associated with muscle contractions, reducing the perception of effort and extending the time participants could cycle.
According to the team, this was because the exercise felt lighter after the stimulation. tDCS had previously been used to improve endurance performance in endurance sports, but how it works exactly was still unclear. These mechanisms have become clearer with this research, according to the researchers.
Excitement or Calmness
In tDCS, two or more electrodes are placed on the scalp, delivering a constant weak current to the brain. The effect of this on the brain depends on polarity. Just as with a battery, you have positive and negative poles and you have to connect the right side of a jumper cable. Similarly, in brain electrostimulation, it also matters which electrode is placed on which side. The side where the electrons enter (cathode) has a calming effect, while the side where the electrons exit, anode, causes an exciting effect.
In addition, the location on the head where they are placed is of great influence on the effect, including the depth of the stimulation. The motor cortex in the brain is responsible for movement. This can also be stimulated by placing the anode above the primary motor cortex (M1) and calmed down by the cathode.
Studies on the effect of electrostimulation on endurance have yielded various results. The university researchers believe this is due to differences in electrode placement. In one study, for example, no effect was found [2]. In that case, the anode was placed above the M1 while the cathode was placed above the right dorsolateral prefrontal cortex. According to the Kent researchers, it is possible that the effect of the anode on the primary motor cortex was reduced or even nullified by the cathode.
So it is not advisable to prepare for the Dam to Dam by taking your old abtronic from the attic and placing it on your head. Further research will need to be done on the optimal placement and direction of the electrodes to make this knowledge practically useful.
Moreover, one may wonder to what extent professional endurance athletes will benefit from this. According to the Kent researchers, the effect is mainly caused by cycling feeling relatively less strenuous after electrostimulation. So, it’s primarily a mental effect.
Indeed, according to this model, which is based on motivational intensity theory, task failure occurs because people voluntary stop exercising when their perception of effort coincides with the maximum effort they are willing to exert in order to succeed in the task (potential motivation).
The difference between physical exhaustion and mental exhaustion is often particularly significant in people who are not used to pushing themselves physically. For some, the idea of working up a sweat and continuing when tired may be difficult to imagine. Such as a former colleague of mine who actually found that concept quite ridiculous. I can imagine that she might be able to cycle longer when it seems to cost her less effort mentally.
For the study, recreationally active people were selected who did at least three hours of cardiovascular training per week. So, they may be used to not giving up at the first signs of fatigue. But they also don’t necessarily have to be accustomed to pushing themselves to the limit like competitive endurance athletes. I wonder how significant such an effect would be in such a group.
Reference
- L. Angius, A.R. Mauger, J. Hopker, A. Pascual-Leone, E. Santarnecchi, S.M. Marcora. Bilateral extracephalic transcranial direct current stimulation improves endurance performance in healthy individuals. Brain Stimulation, 2017; DOI: 10.1016/j.brs.2017.09.017
- Angius, L., Hopker, J.G., Marcora, S.M., and Mauger, A.R. The effect of transcranial direct current stimulation of the motor cortex on exercise-induced pain. Eur J Appl Physiol. 2015; 115: 2311–2319
