Toss on your sweats and bring out your jump rope for brain health: physical exercise can improve memory, learning, and mood states. Let’s look into it further, and start with why it can be difficult to get moving, how to get over that initial reluctance, and go over how advantageous exercise is to brain functioning in children to older adults.

Scientific studies are demonstrating that physical exercise over a longer period changes the structures of our brain, yet adhering to a physically active lifestyle in the first place is a major hurdle for most. We’ve all been there. We’re feeling content and not one shred of our being is saying “let’s put our phone down, get off this comfy chair, change into workout clothes, and then move our bodies a lot, maybe even lift weights!”. It might be just the opposite; a fleeting idea to exercise pops into our head while reading an article touting the benefits of exercise for health, and we immediately think “nah, I’m good right now, maybe tomorrow... or sometime next year”. Good news- this feeling does not mean you are ill-disciplined, or not cut out to make a physically active lifestyle a reality. This feeling of ill-motivation is normal and wired into the brain.

According to neuroscientist Dr. Jennifer Heisz, the author of ‘Move the Body, Heal the Mind’, there are two neurological reasons for our initial resistance to exercise:

1. Our brains evolved to help us survive by hunting and gathering and to avoid danger. Being that this was a tall order to fill, energy conservation was paramount, it wasn’t meaningful to grossly expend it on activities not inherent to survival.

2. Our brains relish being in homeostasis. It may be difficult to convince our brains that we need to temporarily stress out our bodies by physically exerting ourselves for 20-60 minutes,  inevitably shaking up our comfy happy place. The good news is once we get moving, the brain releases neurotransmitters that make us feel good and rejuvenated, and benefit our brain functioning to boot. Exercise is worth the initial shock to the system because it feels rewarding after a few minutes.

In her book, Dr. Heisz explains that moving for a view minutes allows the brain to create the chemical dopamine which activates our reward and motivation system. She then explains that dopamine coupled with the release of endocannabinoids such as the neurotransmitter anandamide, aka ‘the bliss molecule’, contribute to the euphoric sensation or ‘runners high’. This rewarding feeling plays a role in keeping you motivated to continue working out and feel impelled to return.

If you’ve ever wondered why this euphoric feeling occurs during your HIIT session or run, research is shining light into potential mechanisms. It turns out it is not based on the release of chemical endorphins (a class of endogenous opioid neuropeptides that block pain). Rather, it is our bodies' endocannabinoid system. But what exactly is this?

Endocannabinoids are cannabinoid molecules made within [endo] your body that regulate and power a range of processes. Recently it was identified as a mechanism which induced the elated feeling during and post-exercise. Siebers et al. (2021) conducted a study in which physically active participants ran on a treadmill at moderate intensity for 45 minutes and in another session walked 45 minutes on a treadmill, while participants were randomly administered an opioid blocker or placebo. The euphoric feeling and reduction in anxiety were reported post-run in both groups, as well as elevated levels of endocannabinoids. However, a reduction in anxiety and greater feelings of euphoria were not found after the walking session.

Apart from generating a pleasurable and rewarding experience, physical exercise prompts numerous health benefits which are widely known such as heart and respiratory health, muscle function, reducing blood sugar levels, helping maintain a healthy body weight etc. Exercise also contributes to well-being through positive effects on brain neuroplasticity, and can help support memory, creativity, mood states and more. Here are five key benefits that exercise has on brain health:

5 key benefits of exercise and brain health (not an exhaustive list):

1. Exercise produces new brain cells in the hippocampus region.
   In this informative Tedx talk by neuroscientist Dr. Wendy Suzuki, she explains not only does exercise create new brain cells and improve concentration and memory, it additionally helps improve the volume of the hippocampus region and helps improve long-term memory. Dr. Wendy Suzuki describes physical exercise as “giving your hippocampus a boost” and encouragingly illustrates: “we all have the capacity to grow a bigger, fatter, fluffier hippocampus...I like to give people this image of every single time you move your body, it’s like giving your brain this wonderful bubble bath of neurochemicals” (Huberman, 2022).
   Let’s all applaud this playful re-framing of physical exercise: a bubble bath of neurochemicals for my brain to grow and build a fluffier hippocampus? Yes, please! Say no more! I’d love to see fitness class names include not only the muscle focus of the class, but also the cognitive benefits to make it more mainstream knowledge. How about-”Bum, tums, and fluffy hippocampi”, or “AAMC: arms, abs, memory, and cognition”.

2. Exercise may help persons with anxiety, depression, and post-traumatic stress disorder (PTSD). 
   Aerobic exercise releases mood-boosting neurotransmitters such as serotonin, dopamine, noradrenaline, and endorphins,and it can to lift the mood states of persons living with anxiety, depression, and PTSD. Researchers found that teenagers hospitalized for anxiety and depression showed positive effects in depression scores after a 6-week structured, group physical exercise program in addition to their treatment plans (Phillippot et al., 2022).
   Exercising can help you feel more resilient, as Wolf et al., (2021) found that during Covid-19 restrictions, persons reporting physical activity experienced less depression and anxiety than those not reporting physical activity behaviours. Ley et al., (2018) found group physical activity induced a motivational-restorative effect for participants with PTSD. The group physical exercise sessions offered a positive distraction effect of being in the present moment and an exposure effect which affected how the participants’ minds responded to physical sensations and exertion during exercise. 

3. Exercise offers protection from neurocognitive decline. 
   Dr. Wendy Suzuki explains that the hippocampus and prefrontal cortex grow with physical exercise (especially exercise that drives up your heart rate), thus giving your brain more volume which offers protection from neurocognitive diseases and age-related cognitive decline. In fact, high-intensity exercise has been shown to improve memory performance in older persons compared to moderate continuous exercise and stretching (Kovacevic, et al., 2020).
   Physical exercise releases neurotrophins which are excellent for protecting our brain processes “due to their ability to promote neuronal survival, development, and maintenance, as well as neurogenesis and synaptic plasticity” (Bonanni et al., p.13, 2022). The release of neurotrophins through regular physical activity can help protect our brain from age-related neurological decline, further cementing exercise as medicine.

4. Duration counts: a 20-minute workout increases brain-derived neurotrophic factor (BDNF).
   BDNF is a protein that contributes to the growth of neurons, neural transmission, plasticity, learning, memory, and the protection of neurons. BDNF has also been touted as ‘miracle-gro’ for the brain. BDNF is produced in the brain a few ways, including the release of lactate via physical exercise (El Hayek et al., 2019). In regards to the exercise-induced muscle burning sensation, your muscles are producing lactate which is then released into the bloodstream, some of which cross the blood-brain barrier and help to increase levels of BDNF in the hippocampus, thus increasing positive factors supporting neuroplasticity. That lactate burn is a good thing! Let’s not banish the burn but welcome it as one of the mechanisms to support brain health.
   Li Qing et al., (2022) conduced a study in 12 male university students, and found that a single 20-minute high-intensity interval training (HIIT) session (30 seconds on/30 seconds rest) elevated BDNF levels more than a single 30-minute HIIT session. This is great news for those short on time! HIIT has been shown to increase levels of BDNF at a slightly higher level compared to continuous exercise (Saucedo et al., 2015). Aerobic exercise is key to increasing circulating BDNF levels in the brain. Choose an aerobic activity you find enjoyable and try to keep your heart rate elevated for at least 20 minutes, and build up to 5 to 7 days a week.

5. From jumping rope to running sprints-exercise boosts learning.
   I’ve covered this before, and I will gladly write it again and again: exercise supports concentration, creativity, and learning! Here is some great news for parents, caregivers, and teachers out there; jump rope breaks have been shown to increase learning potential in children. Jumping rope is inexpensive, accessible, and can give kids a learning boost.
   A study from Burdack & Schöllhorn (2022) found that math learning improved after school children attended a 15-minute math lecture followed by a 1-minute jump rope with a 30-second break for three minutes. This may be attributed to aerobic exercise increasing BDNF levels which “leads to activation of signaling pathways that result in exercise-dependent enhanced learning and memory formation” (Sleiman et al., 2016). Another study with university students showed that three, five-minute body-weight exercise breaks during a 50-minute video lecture improved learning and concentration more than those without breaks, and for those with gaming breaks (Fenesi, et al., 2018). Winter et al., (2007) found that exercise breaks with high-intensity running sprints increased neurotransmitters and BDNF levels, and vocabulary learning was 20% faster compared to moderate aerobic exercise or sedentary learning breaks.

Try it yourself: Personal study for supported learning through exercise:

Try conducting a personal study to see potential differences in learning with exercise breaks.

• Incorporate short exercise breaks of 3-5 minutes for every 15 minutes of studying/watching lecture videos.

• Write a few questions for yourself based on the material, and answer them after the lecture.  

• Do this for a week or even a day for a faster comparison, and the following week/day omit the exercise breaks and continue to write and answer content questions based on the lectures.

• See for yourself if exercise breaks help you retain information longer and access the information quicker.

• For the exercise breaks; aim to get your heart rate up as opposed to breaks with light stretching.

• Exercise ideas: jumping jacks, high knees, butt kicks, jog on the spot, light hops on the spot, sprint on the spot, squat jumps, squat pops, fast feet, and jumping rope. If you have the space to safely do so: lateral shuffles, lunge jumps, mountain climbers, and burpees.

Exercise is medicine - it causes functional and structural changes not only in your muscles and joints, but in your brain with a cascade of neurochemicals whichn support brain health.  

With Green Blue Active, I advocate for people to move more when they can (especially outdoors), and to believe in themselves as capable of making healthy changes.

Let’s shift the idea of physical exercise as being frivolous to being an essential part of your self-care regime.

I hope this article influences you to move a bit more and consider exercise as a tool for brain health and learning.

References

Bonanni, R., Cariati, I., Tarantino, U., D'Arcangelo, G., & Tancredi, V. (2022). Physical Exercise and Health: A Focus on Its Protective Role in Neurodegenerative Diseases. Journal of functional morphology and kinesiology, 7(2), 38. doi.org/10.3390/jfmk7020038

Burdack, J., & Schöllhorn, W. I. (2022). Cognitive Enhancement through Differential Rope Skipping after Math Lesson. International journal of environmental research and public health, 20(1), 205. doi.org/10.3390/ijerph20010205

El Hayek L., Khalifeh M., Zibara V., Abi Assaad R., Emmanuel N., Karnib N., El-Ghandour R., Nasrallah P., Bilen M., Ibrahim P., et al. Lactate Mediates the Effects of Exercise on Learning and Memory through SIRT1-Dependent Activation of Hippocampal Brain-Derived Neurotrophic Factor (BDNF) J. Neurosci. 2019;39:2369–2382. doi: 10.1523/JNEUROSCI.1661-18.2019.

Fenesi, B., Lucibello, K., Kim, J. A., & Heisz, J. J. (2018). Sweat so you don’t forget: Exercise breaks during a University Lecture increase on-task attention and learning. Journal of Applied Research in Memory and Cognition, 7(2), 261–269

Huberman, A. (Host). (2022, May 22). Dr. Wendy Suzuki: Boost Attention and Memory with Science-Based Tools (No.73) [Video Podcast Episode]. In Huberman Lab Podcasts. www.youtube.com/watch

Kovacevic, A., Fenesi, B., Paolucci, E., & Heisz, J. J. (2020). The effects of aerobic exercise intensity on memory in older adults. Applied physiology, nutrition, and metabolism = Physiologie appliquee, nutrition et metabolisme, 45(6), 591–600. doi.org/10.1139/apnm-2019-0495

Ley, C., Rato Barrio, M., & Koch, A. (2018). “In the Sport I Am Here”: Therapeutic Processes and Health Effects of Sport and Exercise on PTSD. Qualitative Health Research, 28(3), 491–507. https://doi.org/10.1177/1049732317744533

Li Q, Zhang L, Zhang Z, Wang Y, Zuo C and Bo S (2022) A Shorter-Bout of HIIT Is More Effective to Promote Serum BDNF and VEGF-A Levels and Improve Cognitive Function in Healthy Young Men. Front. Physiol. 13:898603. doi: 10.3389/fphys.2022.898603

Philippot, A., Dubois, V., Lambrechts, K., Grogna, D., Robert, A., Jonckheer, U., Chakib, W., Beine, A., Bleyenheuft, Y., & De Volder, A. G. (2022). Impact of physical exercise on depression and anxiety in adolescent inpatients: A randomized controlled trial. Journal of affective disorders, 301, 145–153. https://doi.org/10.1016/j.jad.2022.01.011

Saucedo Marquez, C. M., Vanaudenaerde, B., Troosters, T., & Wenderoth, N. (2015). High-intensity interval training evokes larger serum BDNF levels compared with intense continuous exercise. Journal of applied physiology (Bethesda, Md. : 1985), 119(12), 1363–1373. doi.org/10.1152/japplphysiol.00126.2015

Siebers, M., Biedermann, S. V., Bindila, L., Lutz, B., and Fuss, J. (2021). Exercise-induced euphoria and anxiolysis do not depend on endogenous opioids in humans. Psychoneuroendocrinology. 126:105173. doi: 10.1016/j.psyneuen.2021.105173

Sleiman, S. F., Henry, J., Al-Haddad, R., El Hayek, L., Abou Haidar, E., Stringer, T., Ulja, D., Karuppagounder, S. S., Holson, E. B., Ratan, R. R., Ninan, I., & Chao, M. V. (2016). Exercise promotes the expression of brain derived neurotrophic factor (BDNF) through the action of the ketone body β-hydroxybutyrate. Elife, 5, e15092. doi.org/10.7554/eLife.15092

Winter, B., Breitenstein, C., Mooren, F. C., Voelker, K., Fobker, M., Lechtermann, A., Krueger, K., Fromme, A., Korsukewitz, C., Floel, A., & Knecht, S. (2007). High impact running improves learning. Neurobiology of learning and memory, 87(4), 597–609. doi.org/10.1016/j.nlm.2006.11.003

Wolf, S., Seiffer, B., Zeibig, J.-M., Welkerling, J., Brokmeier, L., Atrott, B., Ehring, T., & Schuch, F. B. (2021). Is physical activity associated with less depression and anxiety during the COVID-19 pandemic? A rapid systematic review. Sports Medicine, 51(8), 1771–1783. doi.org/10.1007/s40279-021-01468-z

Zhao, K., Hu, Z., Wang, T., Tian, L., Wang, M., Liu, R., Zuo, C., & Jihua, W. (2022). Acute effects of two different work-to-rest ratio of high-intensity interval training on brain-derived neurotrophic factor in untrained young men. Frontiers in physiology, 13, 988773. doi.org/10.3389/fphys.2022.988773