How Breaking a Sweat Benefits Your Brain

Physical exercise has long been advocated for its myriad of benefits to the human body. From improved cardiovascular health to increased muscular strength, the advantages of regular physical activity are well-documented. However, the effects of exercise extend far beyond just physical well-being. Growing research suggests that exercising also has profound impacts on our brain, ranging from cognitive enhancement to mood stabilization. Here’s a deeper dive into the mechanisms and outcomes of exercise on our brain health.

Physical exercise (PE) holds a unique relationship with brain plasticity, influencing our cognitive processes and overall well-being. Evidence from both experimental and clinical studies supports the notion that PE triggers significant structural and functional transformations in the brain, culminating in extensive biological and psychological advantages(Mandolesi et al., 2018).

Before diving deeper, let’s demystify a common misconception. Many use the terms ‘physical exercise’ (PE) and ‘physical activity’ (PA) interchangeably, though they signify different concepts. As defined by the World Health Organization (2010), PA encompasses any bodily movement generated by skeletal muscles, translating to energy expenditure. 

This broad category includes everyday tasks and leisure actions, viewed as cornerstones of a healthy lifestyle. In contrast, PE is a subset of PA, characterized by its planned, structured, and repetitive nature. Its core objective is enhancing or preserving specific physical fitness components. Think of structured routines like aerobic or anaerobic training, marked by set frequencies, durations, and intensities(Mandolesi et al., 2018).

Neurogenesis: A Revival of Brain Growth

Historically, it was believed that the brain’s ability to produce new neurons (a process called neurogenesis) was restricted to early childhood. Recent scientific discoveries, however, have toppled this notion, demonstrating that the adult brain can indeed produce new neurons. Exercise, particularly aerobic activities like running and cycling, appears to play a significant role in promoting this process.

The University of Cambridge conducted a revealing study that showcased how running stimulates the production of new neural cells in the hippocampus, a pivotal region in the brain linked with memory and learning (Firth et al., 2018). This implies that activities prompting cardiovascular health can potentially enhance our ability to learn and remember.

The Miracle of Brain-Derived Neurotrophic Factor (BDNF)

At a molecular level, exercise facilitates the release of various proteins and growth factors that contribute to brain health. Among these, Brain-Derived Neurotrophic Factor (BDNF) stands out. BDNF aids in the survival of existing neurons and propels the growth of new neurons and synapses(Szuhany et al., 2015). Think of it as a “fertilizer” for the brain; it helps neurons flourish and interconnect.

The intricate dance between physical exercise and our brain health can be credited, in large part, to an array of neurotrophic factors, chief among them being BDNF, IGF-1, and VEGF.

BDNF functions as a nurturing factor for neurons, supporting their survival, growth, and, importantly, the adaptability of their connections, termed synaptic plasticity. BDNF’s essential role in the relationship between exercise and enhanced brain function can’t be overstated. It’s the linchpin driving the boost in hippocampal neurogenesis – the birth of new neurons – following exercise(Liu & Nusslock, 2018; Mandolesi et al., 2018). 

BDNF levels in the brain shoot up after both short-term and extended exercise periods(Mandolesi et al., 2018). Notably, these heightened levels linger for at least a fortnight post-exercise (Berchtold et al., 2010). This molecule, through its action on the TrkB receptor, strengthens synaptic connections and memory circuits(Liu & Nusslock, 2018; Mandolesi et al., 2018). When we exercise, our bodies see an upsurge in BDNF levels, leading to improved cognitive functions and heightened brain plasticity (Szuhany et al., 2015).

IGF-1 and VEGF also deserve recognition in this neural ensemble. IGF-1, implicated in memory and brain plasticity, especially as we age, is crucial for brain health. Its interplay with BDNF appears to be pivotal for the synaptic enhancements seen post-exercise. (Mandolesi et al., 2018). 

The locale of adult hippocampal neurogenesis, interestingly, is adjacent to the hippocampus’s microvasculature. Exercise boosts levels of both IGF-1 and VEGF, stimulating the growth of both new neurons and blood vessels in the brain. VEGF, in particular, focuses on the proliferation and survival of vascular endothelial cells (Mandolesi et al., 2018). 

In sum, as one embarks on a physical fitness journey, it’s not just muscles that get a workout. Exercise charges a biochemical cascade, led by BDNF, IGF-1, and VEGF, which carves pathways to a fortified brain and heightened cognitive capacities.In essence, consistent physical activity can make our brains more adaptable and resilient.

The Mood Enhancer: Battling Stress and Depression

The link between exercise and mood enhancement is well-established. Physical activities trigger the release of endorphins, neurotransmitters that act as natural painkillers and mood elevators. The resultant “runner’s high” isn’t just an anecdotal phenomenon; it’s a real, physiological response.

Moreover, exercise acts as a potent countermeasure to stress. By modulating the release of stress hormones like cortisol and adrenaline, physical activity can substantially dampen the adverse effects of chronic stress on the brain (Ratey & Loehr, 2011). For many, this becomes a crucial method for maintaining mental equilibrium in a hectic world.

Memory Boost and Learning Amplification

Our ability to remember and learn isn’t static; it can be enhanced. As mentioned earlier, exercise positively impacts the hippocampus, leading to its growth. A larger hippocampus is often correlated with improved memory functions. People who regularly engage in aerobic exercise, therefore, might find themselves recalling names, dates, and details more efficiently (Erickson et al., 2011).

Furthermore, the cognitive gains from exercise aren’t restricted to memory alone. Problem-solving, attention, and even verbal skills can see improvements with regular physical activity.

A Shield Against Cognitive Decline

Aging, unfortunately, often brings with it a decline in cognitive abilities. Diseases like Alzheimer’s and other forms of dementia can have devastating effects on individuals and their families. However, exercise offers a beacon of hope. By promoting vascular health and optimizing blood flow to the brain, physical activity becomes a frontline defense against cognitive degeneration (Barnes & Yaffe, 2011).

Regular exercise doesn’t just offer a temporary boost in cognition; it provides long-term protection against age-associated brain diseases. By instilling a routine of regular physical activity, we can potentially extend the health of our brain well into our twilight years.

Conclusion

Exercise is not merely a regimen for physical health; it’s a powerful prescription for robust cognitive health. From enhancing learning and memory to staving off cognitive diseases, the benefits of exercise on the brain are extensive and profound. As we understand more about the intricate relationship between physical activity and brain health, one message remains clear: a fit body indeed leads to a fit mind.

References:

Barnes, D. E., & Yaffe, K. (2011). The projected effect of risk factor reduction on Alzheimer’s disease prevalence. The Lancet Neurology, 10(9), 819–828. https://doi.org/10.1016/S1474-4422(11)70072-2

Erickson, K. I., Voss, M. W., Prakash, R. S., Basak, C., Szabo, A., Chaddock, L., Kim, J. S., Heo, S., Alves, H., White, S. M., Wojcicki, T. R., Mailey, E., Vieira, V. J., Martin, S. A., Pence, B. D., Woods, J. A., McAuley, E., & Kramer, A. F. (2011). Exercise training increases size of hippocampus and improves memory. Proceedings of the National Academy of Sciences, 108(7), 3017–3022. https://doi.org/10.1073/pnas.1015950108

Firth, J., Stubbs, B., Vancampfort, D., Schuch, F., Lagopoulos, J., Rosenbaum, S., & Ward, P. B. (2018). Effect of aerobic exercise on hippocampal volume in humans: A systematic review and meta-analysis. NeuroImage, 166, 230–238. https://doi.org/10.1016/j.neuroimage.2017.11.007

Liu, P. Z., & Nusslock, R. (2018). Exercise-Mediated Neurogenesis in the Hippocampus via BDNF. Frontiers in Neuroscience, 12. https://doi.org/10.3389/fnins.2018.00052

Mandolesi, L., Polverino, A., Montuori, S., Foti, F., Ferraioli, G., Sorrentino, P., & Sorrentino, G. (2018). Effects of Physical Exercise on Cognitive Functioning and Wellbeing: Biological and Psychological Benefits. Frontiers in Psychology, 9. https://doi.org/10.3389/fpsyg.2018.00509

Ratey, J. J., & Loehr, J. E. (2011). The positive impact of physical activity on cognition during adulthood: a review of underlying mechanisms, evidence and recommendations. Revneuro, 22(2), 171–185. https://doi.org/10.1515/rns.2011.017

Szuhany, K. L., Bugatti, M., & Otto, M. W. (2015). A meta-analytic review of the effects of exercise on brain-derived neurotrophic factor. Journal of Psychiatric Research, 60, 56–64. https://doi.org/10.1016/j.jpsychires.2014.10.003