Physical activity has been central in the life of humans for most of our history, shaping our evolutionary physiology and needs. However, recent times have featured increasingly sedentary lifestyles and highly energetic diets, and the health consequences of these are becoming increasingly clear. Being physically active can improve brain health, help manage weight, reduce the risk of disease, strengthen bones and muscles, and improve one’s ability to complete everyday activities. Adults who spend less time sitting and do any amount of moderate to vigorous exercise have substantial health benefits. In particular, exercise has a number of clear neurological benefits for individuals of all ages and backgrounds.
Studies have demonstrated that every time one moves their body, a number of beneficial neurotransmitters, including dopamine, norepinephrine, serotonin and acetylcholine, are released in the brain 1. Regular exercise can help individuals sleep and feel better, while decreasing stress levels, including in the form of social anxiety, and helping with emotional regulation. Overall, an individual who regularly exercises experiences general neurological benefits in the form of increased focus, energy, and attention 2.
Some of these benefits act via increased neurogenesis, or the formation of new brain cells, including the production of the very potent brain derived neurotrophic factor (BDNF) 3,4. As a result, exercise specifically improves memory and thinking processes 5 while slowing cognitive decline. Indeed, one study revealed that cognitive decline is almost twice as common among adults who are inactive compared to those who are active 6.
Longitudinal studies in humans suggest that regular exercise can increase the size of the hippocampus and prefrontal cortex 7. Both of these are susceptible to neurodegenerative diseases such as dementia and Alzheimer’s, which means that exercise helps minimize the risk of their occurrence.
Exercise can also result in a number of long-term changes, even a longer life span. There are several mechanisms underlying the benefits of physical activity on long-term health, including neurological health. These tend to center on hormones, neurotrophins, and neurotransmitters, the release of which is modulated by exercise, as well as on the intra- and extracellular pathways that regulate the expression of genes 8. More importantly, it is clear that lifestyle and diet can induce epigenetic modifications which modify chromatin structure and therefore gene expression, thus causing even heritable metabolic benefits 8. Clearly, the broad benefits of exercise are not only immediate, but can have lasting, even inter-generational effects.
How should one exercise? For the greatest benefit, adults tend to need at least 150 minutes of moderate intensity physical activity weekly, or 75 minutes of vigorous-intensity activity weekly. For increased focus and concentration, the best are activities include brisk walking, running, swimming, cycling, playing tennis or jumping rope. The exercise can be spread out throughout the week, for example, in the form of 30 minutes a day, 5 days a week. In addition, everyone would benefit from muscle strengthening activities two or more days a week, while adults 65 and older are encouraged to do balance activities three days a week 9. The government has published clear physical activity guidelines which can inform a regular exercise regimen 10.
It can feel discouraging to not meet the recommended targets. However, remember that no matter your age or fitness level, any amount of exercise has a number of neurological but also broad health benefits with lasting impacts.
References
1. Working out boosts brain health. Available at: https://www.apa.org/topics/exercise-fitness/stress. (Accessed: 28th September 2023)
2. 10 Neurological Benefits of Exercise – PositivePsychology.com. Available at: https://positivepsychology.com/exercise-neurological-benefits/. (Accessed: 28th September 2023)
3. Konopka, L. M. How exercise influences the brain: a neuroscience perspective. Croat. Med. J. 56, 169 (2015). doi: 10.3325/cmj.2015.56.169
4. Is exercise actually good for the brain? | Science | AAAS. Available at: https://www.science.org/content/article/exercise-actually-good-brain. (Accessed: 28th September 2023)
5. Regular exercise changes the brain to improve memory, thinking skills – Harvard Health. Available at: https://www.health.harvard.edu/blog/regular-exercise-changes-brain-improve-memory-thinking-skills-201404097110. (Accessed: 28th September 2023)
6. Omura, J. D. et al. Cross-sectional association between physical activity level and subjective cognitive decline among US adults aged ≥45 years, 2015. Prev. Med. (Baltim). (2020). doi:10.1016/j.ypmed.2020.106279
7. Ding, Q., Vaynman, S., Akhavan, M., Ying, Z. & Gomez-Pinilla, F. Insulin-like growth factor I interfaces with brain-derived neurotrophic factor-mediated synaptic plasticity to modulate aspects of exercise-induced cognitive function. Neuroscience (2006). doi:10.1016/j.neuroscience.2006.02.084
8. Di Liegro, C. M., Schiera, G., Proia, P. & Di Liegro, I. Physical activity and brain health. Genes (2019). doi:10.3390/genes10090720
9. Physical Activity for a Healthy Weight | Healthy Weight, Nutrition, and Physical Activity | CDC. Available at: https://www.cdc.gov/healthyweight/physical_activity/index.html#howMuch. (Accessed: 28th September 2023)
10. Current Guidelines | health.gov. Available at: https://health.gov/our-work/nutrition-physical-activity/physical-activity-guidelines/current-guidelines. (Accessed: 28th September 2023)