Newsletter #152: Boosting Your Brainpower Through Exercise 🧠✨
Happy weekend friends, and welcome to the newest edition of the humanOS newsletter!
This week, we looked at how and why exercise seems to enhance cognitive performance in multiple domains, but especially in executive function and in learning and memory. We examined some studies showing how exercise and physical fitness is linked to better school grades in children, and got some insight into the underlying molecular mechanisms that link physical activity to better cognition.
Finally, we also learned why taking notes old school style - with a pen and paper - might be the best way to go when you are trying to learn something new.
To learn more, scroll on down 👇🏼
This Week’s Research Highlights
✍🏻 Writing on physical paper may offer advantages for learning and memory.
Researchers recruited a total of 48 participants and performed a series of tests to determine memory skills, personal preferences for analog vs digital methods, and other demographic characteristics. The subjects were equally sorted into three groups based on these characteristics to ensure that they did not confound the results. Then, the volunteers read a fictional conversation between characters discussing their plans for the future, including 14 different class times, assignment due dates, and personal appointments. Depending on the group to which they were assigned, the volunteers recorded this fictional schedule using either 1) a paper datebook and pen, 2) a calendar app on a digital tablet with a stylus, 3) a calendar app on a smartphone with a touchscreen keyboard. After one hour, including a break and an interference task, volunteers were asked a range of multiple choice questions about the schedule while inside a magnetic resonance imaging scanner to measure changes in blood flow around the brain.
The subjects who used analog methods were more accurate than their digital counterparts on simple test questions. Volunteers who used the analog methods were also more efficient, taking 25% less time to fill in the calendar compared to the tablet and smartphone users. But the brain imaging data was the most interesting finding. Subjects who used paper showed more brain activity in the hippocampus, as well as areas associated with language and imaginary visualization. The researchers attribute this to the richer spatial details yielded by paper and pen. The hippocampus is involved not just in memory encoding and retrieval, but also in spatial memory. Corresponding author Kuniyoshi Sakai explains: “Digital tools have uniform scrolling up and down and standardized arrangement of text and picture size, like on a webpage. But if you remember a physical textbook printed on paper, you can close your eyes and visualize the photo one-third of the way down on the left-side page, as well as the notes you added in the bottom margin.”
🏋️ Intense exercise may boost memory and mood in part through lactate production.
It has been known for some time that physical exercise enhances neuroplasticity, and one mediator of this effect is the neurotrophin brain derived neurotrophic factor (BDNF), a molecule associated with neurogenesis, synaptogenesis, and learning. Circulating BDNF levels increase following physical exercise, however the underlying molecular mechanisms that link exercise to BDNF-dependent pathways have not yet been fully elucidated. Some recent research is starting to point to lactate as a potential mediating factor. Lactate has historically been thought of as merely a waste product of anaerobic metabolism (you’ve experienced it as the characteristic “burn” felt in your muscles when training hard), but lactate appears to actually be an important signaling molecule. It can cross the blood-brain barrier, and lactate uptake in the brain increases by more than two-fold during exercise. Studies that use blood lactate to monitor exercise intensity have shown that higher lactate concentrations are correlated to increased levels of BDNF, and voluntary exercise promotes hippocampal BDNF expression and improves learning in a lactate dependent manner in rodents. But how do we know that lactate itself is playing a role, rather than just being a marker of physical exercise? When researchers administered intravenous infusions of sodium-lactate to resting human participants, BDNF levels rose significantly. This would also perhaps explain why high intensity interval training seems to be more effective for elevating BDNF levels, compared to continuous exercise.
🧠 Children who are physically fit have larger brains, and better cognitive performance.
Researchers examined data from participants in the ActiveBrains Project (n = 100 children, mean age 10.0 ± 1.1 years). Physical fitness was measured through a field-based fitness test battery as well as a maximal treadmill test in the laboratory. Brain volume was evaluated through magnetic resonance imaging, and intelligence and cognitive performance were assessed through standardized tests. Statistical analyses revealed that various fitness components were predictors of global brain volume as well as gray and white matter, which in turn was linked to better cognitive performance as well as academic achievement. These study results line up with previous similar findings observed in adults. Lead author Cristina Cadenas-Sánchez says: "Our research shows the importance of being in good physical shape at an early age for better brain development in such a critical stage as childhood."
📚 Children with higher cardiorespiratory fitness have better grades in school due to the effect of physical fitness on executive function.
Researchers in Geneva visited eight schools in Switzerland and conducted cognitive and physical tests on students aged 8-12 (n = 193). These children performed the shuttle run test to assess cardiorespiratory fitness, then underwent a battery of cognitive tests designed to assess the children’s abilities in the three main executive functions: inhibition, cognitive flexibility, and working memory.
The researchers were also granted access to the students’ grades in math, French 1, and French 2. After combining the obtained data, the researchers determined that cardiorespiratory fitness was linked to better executive function, and this impact on executive function in turn is related to better academic performance. Increased cognitive flexibility specifically - the ability to move between tasks or responses based on task demands - appeared to mediate the relationship between better physical fitness and better academic performance.
Question of the Week
🤔 It has been said before that if you want to slow down time, you should drop down and get into the plank position. What is the current world record for the longest continuous plank?
💡 Answer
Podcasts We Loved This Week
- Chris Packard: LDL cholesterol, apoB, and atherosclerosis. Via Sigma Nutrition Radio.
- Sidarta Ribeiro: What can sleeping octopuses tell us about memory? Via Science Friday.
Products We Are Enjoying
Creatine monohydrate
If you're exercising hard (and generating some BDNF 🧠), there is perhaps no better and more cost-effective supplement to aid your cause than creatine. It is best known for its impressive effects on acute exercise performance, however it may also improve your brainpower. For some more info on the benefits of this underappreciated supplement, check out this article. I bet you’ll want to give it a shot after reading.
humanOS Catalog Feature of the Week
How-to Guide - Ergogenic Aids (Athletic Enhancers)
An ergogenic aid is simply a supplement that enhances physical performance. Dietary intake of these substances can, in theory, affect training adaptations in a couple of different ways. They can achieve this by simply increasing the exercise stimulus from a single training bout - basically just enabling an athlete to train longer or harder, or reducing perceived exertion. But they may also be able to affect gains in endurance by altering cellular responses to exercise-induced stress.
Importantly, these changes in cell signaling may not be universally beneficial from the standpoint of adaptation. For example, it is theoretically possible that a supplement could simultaneously make it easier for an athlete to exercise hard, but also have effects on cellular signaling that actually have a long-term negative impact on the adaptive response to training.
In this guide, we review some of the most rigorously researched supplements (including LactiGo), discuss how best to use them, and talk about why some supplements that sound like a good idea may actually not be helpful at all. If you are looking for a quick reference sheet of the latest evidence-based guidance on supplements to maximize your performance and adaptations, check it out! 👀