11 Mar Can high intensity exercise fight off dementia?

Dementia is the second leading cause of death of Australians, contributing to 5.4% of all deaths in males and 10.6% of all deaths in females each year. These numbers are constantly on the rise, and there’s no cure. But there are things you can do to reduce your risk of developing the disease, and exercise is one of them. We take a look at the link between high intensity exercise and dementia.

“I can’t remember where I put my keys”. It’s a common phrase among older individuals that’s brushed off as a normal part of ageing. But why can some people live to 100 and still remember where they put their keys while others are diagnosed with dementia? We still don’t know the exact answer to this question. What we do know is that certain risk factors increase the likelihood of a dementia diagnosis. The good news? Exercise can help with most of them!

What are the modifiable risk factors for Dementia?

There are certain modifiable risk factors that you can control. These include:

• Midlife obesity
• Physical inactivity
• Midlife high blood pressure
• Smoking
• Low educational attainment
• Depression
• Diabetes

How can exercise help?

Aerobic exercise, especially at a high intensity, has been shown to improve cardiovascular health by decreasing blood pressure, improving glucose control, and improving body composition. However, it also has benefits in the brain. It can improve executive function, which is how you process new information. It also preserves the size of the hippocampus, which is the part of the brain that stores new memories. Lastly, it can elevate blood biomarkers that promote new neuron cell growth.

Decreased cardiorespiratory fitness is also a crucial factor when it comes to dementia risk. Cardiorespiratory fitness as defined by the ability of the body to utilise maximal oxygen uptake, and is commonly referred to as your VO2max. It has been found to be a greater predictor of the progression of dementia than physical activity participation alone. Therefore, being able to improve your cardiorespiratory fitness by increasing the intensity that you exercise, is one way you can help protect your brain.

Does that mean I have to start running?

No! Performing exercise at a high intensity does not mean you need to join the local running squad or start doing hill sprints. High intensity exercise simply has to elevate your breathing rate by enough to make it difficult to hold a conversation. You can add in high intensity bursts of exercise by walking more hills or increasing the speed you walk during small sections of the walking that you are currently doing.

Performing high intensity exercise safely

High intensity exercise can be uncomfortable and cause issues if your body isn’t ready yet. Three tips to safely perform high intensity exercise are:

1. Slowly build up your intensity

If you are currently not exercising, start by going for a walk around the block. When this becomes easy, start walking between certain signs a little bit quicker. If you’re already walking regularly, try changing your walking track to include more hills and maintain your speed or keep the same track and increase your pace by walking more briskly or jogging.

2. Make sure you have a warm up and cool down

Your joints and heart will thank you for slowly building up your intensity during an exercise session. It gives the muscles time to warm up and support your joints when exercising and it also gives the heart time to increase blood flow to the working muscles. The same goes for the cool down. Give your heart and muscles time to recover slowly after exercise by gradually decreasing your intensity.

3. Ensure you see a medical professional if you have any adverse effects

Exercising at a high intensity is safe for the majority of people, but if you’re increasing your exercise intensity, listen to your body. Due to the higher demands placed on the muscles, joints and heart, you should stop exercising if you feel pain and seek appropriate medical advice.

What else can I do to help my brain?

High intensity resistance training – lifting weights that feel heavy for you and progressively get harder as you get stronger – is another way to help your brain. Not only does it promote independence when performing activities of daily living, it also helps reduce frailty which has recently been identified as another risk factor for dementia.

Engaging with other people is also important to keep the brain stimulated, so exercising in groups is a great way to get the benefits of exercise and maintain social interaction in one go!

Who should I see if I want more information about exercise?

If you want help to start exercising, or to lift your exercise intensity, it’s important to seek expert advice. Those living with, or at risk of developing a chronic condition, should speak to an Accredited Exercise Physiologist (AEP). They have the skills and knowledge to prescribe safe, graded and effective exercise interventions for people of all ages and levels of health. To find an AEP near you, click here.

Emily is an Accredited Exercise Physiologist and is currently undertaking a PhD researching strength and high intensity training for individuals with mild cognitive impairment.