Why is Exercise so Important for Brain Health? Exploring the link between movement and memory

Do you sometimes walk into a room and completely forget why you're there? Or, find yourself looking in the fridge with no idea of why you opened the fridge door? How about, enthusiastically making a point about something super interesting, then realising you have no idea of where you were going with what you were saying?

Yep, me too. I remember a time when I’d regularly be rifling through my make-up bag and realise, I had no idea what on earth I was looking for. This happened quite a lot! And yes, it made me worry - “if my brain is like this now, how bad will it be in another 20 years?! Where is this heading?”

Now, as a nutritional therapist specialising in brain health, I’ve got a better idea of what these memory lapses really mean (it’s not dementia!) and how to manage my nutrition and lifestyle to minimise them.

One of the big guns in my arsenal for keeping my brain sharp is undoubtably consistent exercise.

I used to think voluntary exercise was not for me. I only really did it for vanity, and even then, I didn’t put much effort into it. The idea that moving my body could actually protect my brain from cognitive decline just wasn't on my radar yet.

But now I know, and the research shows, that regular movement is one of the most powerful tools we have for protecting our cognitive health. Consistent movement is something we need to learn to enjoy, even if you’re still getting over the trauma of always getting picked last for the school sports teams (I remeber that all too well!).

In this post, we’ll explore why exercise is so important for brain health, memory, and long-term cognitive function. I'll explain why it's worth prioritising even if you were hopeless at sport at school.

Why Is Exercise Important For Brain Health?

When most people think about the benefits of exercise, they usually associate it with cardiovascular health or body composition (1). Brain benefits tend to get overlooked. But to function well, your brain needs oxygen-rich blood, a stable energy supply, and the ability to grow new connections. Exercise directly supports all three (2).

Now let’s think of your brain as a very fancy computer…

Exercise grows brain cells

Exercise triggers production of neurotropic factors like BDNF (Brain-Derived Neurotrophic Factor) (2), which acts like a hardware upgrade for your system. As well as maintaining what you have, it's also adding new neurons (processing units), strengthening the connections between them, and protecting existing neurons from damage.

When a computer has more RAM and better processors, it can handle increasingly complex tasks more efficiently. Similarly, when a brain has more BDNF, this translates to better memory, improved learning capacity, and reduced risk of cognitive decline (3). Exercise may be one of the most reliable ways to trigger these "hardware upgrades" naturally.

Exercise makes your brain a protective environment

Chronic inflammation is one of the primary drivers of cognitive decline. It damages brain cells, disrupts communication between neurons, and speeds the aging process in the brain (2). In computer terms, it’s like it’s running too hot with malware constantly attacking the system, damaging components, disrupting communication between programs, and causing more wear and tear on the whole system.

Exercise acts like installing a top-grade cooling system and comprehensive antivirus protection. By reducing inflammatory markers throughout your body, including in your brain (2), exercise may help to create a protective environment where your neurons can work at their best.

Exercise improves nutrient delivery

Every time you move your body, your heart pumps more blood around your system, increasing blood flow, and therefore nutrient delivery, to your brain (4). A bit like if your computer's power supply was upgraded so that all components could get consistent, reliable power.

Regular exercise improves the health and flexibility of your blood vessels (like replacing old, frayed cables with new, high-quality ones), increasing the efficiency of this delivery system over time. It may also support the growth of new blood vessels (more power connections) and strengthen the blood-brain barrier (like a surge protector gatekeeping what should cross the barrier). (4)

Better blood vessel health is reflected in better brain health, especially in areas responsible for memory and executive function. And you don't need to be training for marathons to experience benefits. Even moderate activity like a brisk walk, or gardening, may improve this delivery system.

Exercise gives your brain a stable energy supply

Your brain uses around 20% of your body's glucose even though it only accounts for approximately 2% of body weight (5). But with age, the brain can become less efficient at using this fuel, especially if insulin resistance develops. It’s like a computer that can't access its power source properly, causing crashes, freezes, and frustratingly slow performance.

Exercise may improve insulin sensitivity throughout your whole body, including in your brain (6). Like when power management settings are optimised in your computer, exercise may improve how effectively your brain cells can use available glucose, maintaining the energy supply needed for clear thinking, good memory, and quick cognitive processing.

Everything works better when your brain has reliable access to energy - focus, memory, decision-making, and mood regulation are all reliant on a stable energy supply.

Exercise improves your cognitive ability

Physical activity increases the production of neurotransmitters (like dopamine, serotonin, and GABA) and growth hormones (2). Like software updates and operating system optimisations that improve how all your computer programs run.

These chemicals regulate your mood, thinking ability, and your brain's capacity to form new connections and adapt to challenges. It's the difference between running an outdated operating system that's slow and glitchy versus having the latest version that runs smoothly, can deal with multiple tasks efficiently, and adapt quickly to new challenges.

What Type of Exercise Is Best For Brain Health?

Really, anything! The important thing is not to overthink or procrastinate, and to just get moving.

While specific mechanisms for cognitive benefit favour certain types of exercise, consistency is the most important thing. For example:

• Resistance training (e.g. weightlifting, Reformer Pilates, circuits, Ashtanga or Hatha yoga) - promotes BDNF production, improves insulin resistance, supports executive function (7).

• Aerobic training (e.g. running, cycling, swimming, rowing) - increases blood flow, reducing inflammation and oxidative stress in the brain, and improves glucose utilisation (7).

• Mixed aerobic/anaerobic (e.g. tennis, padel, squash) – improves focus, executive function and processing speed (8).

• Motor-skill based activities (dancing, tai chi, yoga) – improves connectivity between brain regions, moderately increases neurotropic factors like BDNF, and engages memory, attention and cognitive flexibility (9).

But the best exercise for your brain is the one you will do regularly. A daily 3000 step walk is more impactful than an ambitious gym plan you give up on after two weeks.

Variety is also helpful to experience different types of movement and benefit from different brain supportive mechanisms.

How Much Exercise Do You Need For Brain Health?

The research suggests that it really doesn’t take much movement for your brain to experience benefits.  A recently published paper has shown that as little as 3000 steps each day can delay cognitive decline by an average of 3 years. This goes up to 7 years for adults walking 5000 – 7500 steps a day. (10)

Other studies show that the sweet spot for the most robust cognitive improvements appears to be 45-60 minutes of moderate intensity activity at least 3 times each week (11) . That includes activities like brisk walking, gardening, gentle cycling, Pilates or yoga (with continuous movement). The kind of activity where your heart rate’s up, but you can still talk.

If you are doing more intense activity or resistance training, you need even less time over the week to experience benefits. More activity and intensity generally provides greater benefits (11), but the research is clear that any movement is better than nothing.

How Long Does It Take For Exercise To Improve Brain Health?

Significant cognitive improvement takes more time, but there are changes you may notice straight away.

Within the first hour of a moderate-intensity workout your brain is already responding. Measurable improvements can be found in processing speed and executive function within 20-60 minutes of finishing, but they start to wear off after an hour (12). This means your brain is working faster, is more organised and focused straight after just one workout.

After 12 weeks the difference becomes more noticeable in your daily life as significant improvements in executive function, memory, and attention (13). Brain fog starts to improve and the memory lapses that made you worried about early-onset dementia become less frequent.

Six Months and Beyond of consistent exercise, particularly in older adults, makes the changes more significant and sustained. Now your brain may have grown new blood vessels, increased BDNF production, reduced chronic inflammation, and strengthened neural connections (14).

As you know, the benefits of exercise extend beyond brain function. With consistent movement over time, you may feel fitter, stronger and be protecting your cardiovascular health. But to focus on brain health, your brain may feel clear and sharp so those brain blanks that you were getting so worried about may become less frequent.

There is no guarantee against cognitive decline. But research suggests that regular movement is one of the most powerful protective tools we have can control by affecting so many mechanisms involved in brain health.

The sooner you begin, the sooner you experience those early improvements in mental clarity, and the more protection for your brain you’ll accumulate over your lifetime. And the research consistently shows, it's never too late to start seeing improvements.

Take The "What Was I Saying?" Brain Health Quiz

Now you know why movement is so important for brain health, are you curious about how the rest of your daily habits stack up?

Take this quick brain health habits quiz to help you reflect on other opportunities for protecting your cognitive function. You'll get personalised insights based on your answers, and simple next steps tailored to your situation.

Click here to take the "What Was I Saying?..." Brain Health Quiz

Frequently Asked Questions

Q: I have mobility limitations. Can I still get brain benefits from exercise?

 A: Absolutely. Any increase in movement from your current baseline provides benefits. Chair exercises, gentle stretching, water-based activities, or even seated arm movements can improve circulation and trigger beneficial responses. Work with a physiotherapist to find safe, appropriate options for your situation.

Q: Is exercise alone enough to prevent dementia? 

A: Exercise is one of the most powerful protective factors, but there are many different factors that influence brain health. Sleep quality, nutrition, social engagement, cognitive stimulation, and managing cardiovascular risk are just some of those. Exercise reduces risk but there is no guarantee as to how your cognitive function will age.

Q: What if I've been sedentary for years - is the damage already done? 

A: Studies consistently show that previously sedentary older adults who begin regular exercise see measurable improvements in cognitive function. Your brain retains its ability to respond positively to movement throughout life.

Q: Do I need to exercise intensely to see brain benefits? 

A: No. While higher intensity exercise may provide additional benefits in shorter time, moderate-intensity activity like brisk walking produces significant cognitive improvements. Consistency matters more than intensity.

This information is for general educational purposes and is not a substitute for medical advice. Individual results vary depending on many factors including age, baseline activity, and overall health status. You should always speak with a healthcare professional if you are concerned about any symptoms you are experiencing.

Do You Want To Keep Reading?

This blog post might interest you:

The Reason Your Brain Feels Foggy (Despite Your Healthy Lifestyle)

References

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2. Chen, C., & Nakagawa, S. Physical activity for cognitive health promotion: An overview of the underlying neurobiological mechanisms. Ageing Research Reviews. 2023; 86. https://doi.org/10.1016/j.arr.2023.101868.

3. Müller, P., Duderstadt, Y., Lessmann, V., & Müller, N. Lactate and BDNF: Key Mediators of Exercise Induced Neuroplasticity?. Journal of Clinical Medicine. 2020; 9. https://doi.org/10.3390/jcm9041136.

4. Kaufman, M., Dyrek, P., Fredericson, M., Oppezzo, M., Roche, M., Frehlich, L., & Noordsy, D. The Role of Physical Exercise in Cognitive Preservation: A Systematic Review. American Journal of Lifestyle Medicine. 2023; 18. https://doi.org/10.1177/15598276231201555.

5. Mergenthaler P, Lindauer U, Dienel GA, Meisel A. Sugar for the brain: the role of glucose in physiological and pathological brain function. Trends Neurosci. 2013;36(10):587-597. doi:10.1016/j.tins.2013.07.001

6. Kullmann, S., Goj, T., Veit, R., Fritsche, L., Wagner, L., Schneeweiss, P., Hoene, M., Hoffmann, C., Machann, J., Niess, A., Preissl, H., Birkenfeld, A., Peter, A., Häring, H., Fritsche, A., Moller, A., Weigert, C., & Heni, M. Exercise restores brain insulin sensitivity in sedentary adults who are overweight and obese. JCI Insight. 2022; 7. https://doi.org/10.1172/jci.insight.161498.

7. Dhahbi, W., Briki, W., Heissel, A., Schega, L., Dergaa, I., Guelmami, N., Omri, A., & Chaabène, H. Physical Activity to Counter Age-Related Cognitive Decline: Benefits of Aerobic, Resistance, and Combined Training—A Narrative Review. Sports Medicine - Open. 2025; 11. https://doi.org/10.1186/s40798-025-00857-2.

8. Ingold, M., Tulliani, N., Chan, C., & Liu, K. Cognitive function of older adults engaging in physical activity. BMC Geriatrics. 2020; 20. https://doi.org/10.1186/s12877-020-01620-w.

9. Zou, L., Loprinzi, P., Yeung, A., Zeng, N., & Huang, T. The Beneficial Effects of Mind-Body Exercises for People With Mild Cognitive Impairment: a Systematic Review With Meta-analysis.. Archives of physical medicine and rehabilitation. 2019 https://doi.org/10.1016/j.apmr.2019.03.009.

10. Yau, WY.W., Kirn, D.R., Rabin, J.S. et al. Physical activity as a modifiable risk factor in preclinical Alzheimer’s disease. Nat Med (2025). https://doi.org/10.1038/s41591-025-03955-6

11. Northey, J., Cherbuin, N., Pumpa, K., Smee, D., & Rattray, B. Exercise interventions for cognitive function in adults older than 50: a systematic review with meta-analysis. British Journal of Sports Medicine. 2017; 52. https://doi.org/10.1136/bjsports-2016-096587.

12. Kekäläinen, T., Luchetti, M., Terracciano, A., Gamaldo, A., Mogle, J., Lovett, H., Brown, J., Rantalainen, T., Sliwinski, M., & Sutin, A. Physical activity and cognitive function: moment-to-moment and day-to-day associations. The International Journal of Behavioral Nutrition and Physical Activity. 2023; 20. https://doi.org/10.1186/s12966-023-01536-9.

13. Santos, P., Cavalcante, B., Vieira, A., Guimarães, M., Da Silva, A., Armstrong, A., Carvalho, R., Carvalho, F., & Souza, M. Improving cognitive and physical function through 12-weeks of resistance training in older adults: Randomized controlled trial. Journal of Sports Sciences. 2020; 38. https://doi.org/10.1080/02640414.2020.1763740.

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