The Benefits of Exercise for Your Brain Health

Mar 17th 2023 | By Daniel Angerbauer, MD, MPH, IFMCP

It’s no secret that physical activity is critical for overall health and longevity. Cardio, high-intensity intervals, strength training and balance work are all necessary components of a good exercise plan. What is less commonly known, but equally important, are the effects of physical activity on the brain. A study published in Nature⁰ last year looked at gene expression and potential treatments for Alzheimer’s disease. Out of 250 different modalities, they concluded that the top 3 potential treatments were exercise, exercise, and exercise. Literally, three different data sets put exercise as the first, second and third best potential treatments for Alzheimer’s Disease. This only adds to decades of research demonstrating the importance of exercise for cognitive health. But what types of physical activity are best for the brain?  

Spoiler alert – there isn’t just one type of exercise that is best for brain health, but rather multiple modalities each with their own pros and cons.Just like physical health, it is important for individuals to incorporate aspects of each type of exercise into their routine to achieve optimal cognitive function. With that being said, we will discuss some of the nuances around four different exercise modalities and their research on cognitive function.   

1. Moderate Intensity Steady-State Cardio

Moderate intensity steady-state cardio, also called Zone 2 cardio, refers to exercise performed at a steady pace (constant heart rate) and at an intensity of about 4/10. Examples include brisk walking at an incline or cycling. Research shows that this type of cardio may be specifically helpful for improving memory. A randomized controlled trial published in the Journal of Alzheimer’s Disease showed that regular moderate-intensity exercise resulted in improved memory and an increased size of the hippocampus, a critical area of the brain for memory formation1. Another study showed that this intensity level may benefit memory more than low or high-intensity cardio². 

2. High-Intensity Interval Training

High-Intensity Interval Training (HIIT) involves short bursts of intense exercise followed by periods of rest or low-intensity exercise. HIIT appears to be especially good at boosting levels of BDNF (brain-derived neurotrophic factor), a protein that plays a key role in learning, memory, and neural plasticity³. HIIT may also be especially beneficial for combating age-related declines in brain function. As we age, some cells stop functioning properly but also resist apoptosis (cell death), which doesn’t allow new cells to take their place. These zombie-like cells are called senescent cells. A recent study showed that HIIT, but not steady-state cardio, was specifically beneficial for reducing these types of cells⁴. 

3. Strength Training

Strength training such as lifting weights or using resistance bands has multiple connections to brain health. A large body of research shows that this type of training is especially helpful for improving something called executive function but may not be as helpful for memory⁵. Executive function refers to the cognitive processes that enable individuals to plan, organize, and make decisions. Interestingly, people with lower levels of muscle mass, a condition called sarcopenia, have higher rates of Alzheimer’s disease⁶. Although it is not clear that this link is causal, some evidence suggests this to be the case. Muscle and brain both require large amounts of energy to function properly; the brain takes up to ~20% of our body’s energy requirement even though it accounts for only ~2% of its mass. Strength training helps improve energy production both in the muscles and in the brain by improving mitochondrial function. 

4. Mind-Body Exercise

Mind-body exercises such as tai chi and dance have unique benefits for the brain as they require cognition, balance, spatial awareness and social skills while performing physical movements. Learning a new form of dance may be especially helpful for those already diagnosed with mild cognitive impairment as multiple studies show that it can improve neural plasticity, memory, attention, and psychosocial parameters⁷. Tai Chi also appears to improve cognitive function in older adults with dementia⁸. The drawback to this type of exercise is that the physical activity may not be intense enough to elicit changes in physical fitness or emotional well-being.

To summarize, research clearly shows that exercise has numerous benefits for the brain. It also appears that each type of exercise has its own unique set of cognitive benefits and drawbacks. In the absence of a personalized exercise protocol, we recommend patients to incorporate each of these four modalities into their routine to optimize their brain health and reduce the risk of age-related cognitive decline.

Join Dr. Angerbauer for this informative video on the benefits of exercise for better brain health.

References

0. https://www.nature.com/articles/s41598-022-22179-z
1. https://www.pnas.org/doi/10.1073/pnas.1015950108
2. https://pubmed.ncbi.nlm.nih.gov/36332758/
3. https://www.frontiersin.org/articles/10.3389/fnins.2018.00839/full
4. https://pubmed.ncbi.nlm.nih.gov/36779839/
5. https://pubmed.ncbi.nlm.nih.gov/30627769/
6. https://pubmed.ncbi.nlm.nih.gov/36656981/
7. https://pubmed.ncbi.nlm.nih.gov/36332758/
8. https://pubmed.ncbi.nlm.nih.gov/35839111/