Overclocking the brain with exercise
Crushed that WOD and feeling like you could rediscover General Relativity? That could be due to elevated iAPF, which seems to rise only after a particularly tough workout.
While quietly enjoying the midday sun in Gibraltar, I crawled home after a disappointing workout. It’s been a while since I’ve experienced the hit of a great workout — the endorphines, the cortisol and adrenaline screaming through my veins, the feeling of confidence and peace comes with pushing yourself. Best of all — the mental clarity and sharpness. After a good CrossFit WOD I’d feel like I could solve Fermat’s Last theorem.
As I tried Googling my way out of degrading workout quality, I wanted to learn more about how exercise impacts the brain — and how we might be able to exploit it. I came across a paper by Boris Gutmann et al which suggests a correlation between strenuous physical activity and increased individual Alpha Peak Frequency.
That didn’t mean anything to me at first either, which is why we first need a primer on brainwaves.
Brainwaves.
As you read this, the most detectable neurons in your brain are firing at a rate of somewhere between 13 to 40 cycles per second. This is characterised by Beta brainwaves, and is where we spend most of our waking consciousness. Socialising, performing work-related activities, learning, and focusing on a task all manifest Beta brainwaves.
When you really try to focus in on a task, or are performing an activity that’s particularly demanding, you could find yourself exhibiting predominantly Gamma brainwaves, in the 40–100hz, or cycles per second, range. This is when the CPU fans would start revving up. What’s really interesting to note is that Gamma brainwaves can actually exceed the maximum oscillatory frequency of firing neurons — meaning that their exact generating phenomenon is still somewhat of a mystery.
At some point I’ll inevitably start losing you to daydreams or boredom, if I haven’t already, in which case you’ll slip into an Alpha state. This is characterised by the 8–13Hz frequency band. Alpha is where we tend to find ourselves when we’re relaxed, or in light meditation. It acts as the bridge between the conscious and subconscious mind.
Lastly, Theta and Delta waves are associated with lighter sleep and deeper sleep respectively. Infants will spend most of their time in a state of Delta.
Diagrams courtesy of Muse.
How are brainwaves linked to cognition?
After our little primer of brainwaves, you’d expect Beta and Gamma waves would be key to understanding how higher order cognition manifests in the brain. That doesn’t tell the full story, however. Alpha oscillations have been associated with particular features of information processing, attention selection, and even flow states, or ‘being in the zone’ (particularly at the Alpha-Beta border).
Various papers in the literature argue that a specific measure, known as individual Alpha Peak Frequency can be used to explain some of the factors contributing to general intelligence or ‘smarter brains’.
Individual Alpha Peak Frequency, or iAPF, corresponds to the discrete frequency in the Alpha range (8–13hz) containing the largest amplitude for an individual. This varies on a person-to-person basis, and has been used as a measure to distinguish intelligence between individuals.
Many studies have hypothesised that faster brains are smarter ones, attempting to make correlations between peak Alpha frequencies and measures of intelligence, such as the Weschler Adult Intelligence Scale IQ test. There is ample debate in the literature as to whether or not peak frequencies and intelligence are correlated; as some have found corrlations, while others have not.
It is evident, however, that higher peak frequency is associated with improved working memory characteristics (such as faster accessing of encoded information) and information processing. One study, by Lehtovirta et al. (1996) even found that the peak frequency for adults suffering from Alzheimer’s was significantly lower than that of controls.
So clearly, in sum, the higher this thing is, the better. What does this have to do with exercise then?
Boosting iAPF with exercise.
The following study by Boris Gutmann et al found that iAPF increased with exercise. This isn’t all too surprising, we don’t need experts to tell us that exercise is good for your brain. What is interesting is that the type of exercise had a significant effect on whether or not iAPF would immediately returned to baseline shortly thereafter. The authors found that after a bout of ehuastive exercise, where participants would perform one-legged cycling at near max-capacity, the iAPF continued to rise even 10 minutes after the exercise was completed. This was compared to less strenuous steady-state exercise, where participants cycled well within their capacity.
This is fasctinating. The diagram above shows how the peak frequency rises by almost half a Hertz immediately after completing both types of exercise — but the marked difference here is that with non-strenuous exercise, it quickly returned back to baseline, meanwhile, exhaustive exercise caused the peak frequency to continue rising 10 minutes after the exercise was completed.
The study fails to make any more measurements after the 10-minute mark, but I’d wager that the increased iAPF would last a lot longer, perhaps even a few hours, based off of personal experience seeing enhanced cognition lasting for the rest of the day after intense exercise.
This effect also extends to sensory sensitivity (how well you are able to discern subtle changes in visual patterns and sounds, and so on), as well as reaction times, which also benefit from exercise. Again, these benefits quickly return to baseline after exercising unless the exercise itself was particularly strenuous.
The impact of iAPF on cognition
According to a study correlating the effect of iAPF on general intelligence, higher frequency waves, such as Gamma, are involved in local information processing. Alpha, and other low frequency waves are better for orchestrating communication between more distant neural networks. Intuitively, this makes sense. Consolidating information from many different neural networks requires synchronisation across these networks — meaning that the global frequency would be bottlenecked by the slowest contributing link or neural network.
This is like the difference between the high-speed buses embedded on low-level microprocessors and the longer-range fibre optic cables which power the internet. To help facilitate the kind of global cross-brain-region communication, which generates creative, intelligent insights, we need slower waves in order to synchronise all the different brain regions together. This allows us to pull in various different kinds of information (sensory, declarative, procedural, memories), and process them coherently across brain regions. The level of connectivity between brain regions, or coherence, as it’s otherwise called, is a significant contributor to intelligence.
Next time you hit the gym, give yourself an extra push and your brain will feel like it’s turned on the rest of your day.
That was a summary on some interesting neuroscience studies I’ve been reading lately. My hope was to distill some of the literature and share something you might not have come across.
Note: I must confess — the title, while a valiant attempt at a metaphor, is inaccurate for a number of reasons.
The mental analogue to clock speeds would be the dominant brainwaves found in an EEG. Actual brain overclocking, in a mental sense, would more likely somehow involve increasing the dominant frequencies beyond the upper Gamma limit. I’m not sure how this could be achieved, but I’m guessing 1). Drugs or 2). Focusing really, really hard.
