Nov 2020

Exercise is medicine and why we all have mental health


 | Episode 

By Doctor Izzy Smith

Yes, you heard right, you, me and everyone else has “mental health”. Similar to physical health, it sits on a spectrum and is dependent on a complex relationship of genetic, environmental and social factors, and it is totally normal for it to occasionally be a bit better or worse at different times in our lives.

There is still stigma behind the term “mental health”, and it is often thought of in black and white terms as such as being “good or bad”, “sick or well”, “mad or normal” etc. This is a shame as it’s so far from the truth and stops us thinking of mental health in the same way as physical health i.e. something that we all have, which we should be striving to improve, whilst also purposefully taking steps to protect it.

A useful way I like to visualise and teach mental health to people is to think of it is as a continuum which starts at green and represents being very healthy and then slides along to orange where we’re a bit unwell but not terrible, and then to red which is when we’re very unwell. Orange could be high periods of stress or noticing that we’re a bit anxious or down, whereas red is when things are getting bad and our sleep, work, relationships, and day-to-day lives are being profoundly impacted.

By being self-aware and noticing we’re in the orange, it enables us to take proactive steps to get us back to the green, rather than sliding down into the red. This is not dissimilar to when we’re getting a cold or flu and we decide we need a few days at home to rest to get better quickly, rather than carrying on until it becomes something nasty like sinusitis or pneumonia. These little blips can also be a reminder that we probably need to be taking a bit better care of ourselves to decrease the likelihood of getting into that situation again.

By thinking of mental health in this way, it demonstrates that you don’t need to have been diagnosed with a specific mental illness to be struggling with your mental health (similar to how your physical health can fluctuate even without having a specific illness) and that you can purposefully work on and improve your mental health through simple measures.

When thinking about what we can do to improve our mental health, it’s important to consider the diverse and complex factors that can impact it. These can range from the number of hours of sleep we had last night, stress at work, to our genetics or the experiences we had as children several decades ago.
Because these factors are so varied, there’ll never be one “cure” for mental health problems like depression or anxiety and I’d be very wary of someone promoting a product or service claiming to do this! Instead, each person should have their own recipe for looking after their mental health, dependent on their own experiences and what works for them e.g. this could be regular exercise, reaching out to a friend, meditation, journaling, therapy, medications, or any combination of these. This is definitely not an exhaustive list and there are so many things we can do to support our mental health, but one which has some of the most evidence is physical activity and that’s what I’ll be talking about today.

If we could put the benefits of physical activity into a pill, it would be like a wonder drug with minimal side effects that drug companies would patent and make billions of dollars of profit from. Fortunately for us its free, and even just 15 minutes a day can be beneficial.

There are lots of different reasons why exercise is good for our mental health (routine and structure, working towards a goal, social connectedness), but purely at a neurochemical level, it’s easy to understand why getting huffy and puffy makes us so happy. Dopamine, serotonin, noradrenaline are neurotransmitters involved in regulating our mood and their release are all increased during exercise. Exercise has also been shown to increase a protein called BDNF (brain derived neurotrophic factor) that helps increase neuron cell growth in our brain, especially in an area of the brain called the hippocampus which can often reduce in size in people diagnosed with chronic depression.
The effects of exercise for our mood is well researched. A 2018 study published in the journal Lancet Psychiatry looked at over one million people in the US and revealed that people who regularly exercised had 43% less low mood days and around 20% less mental health symptoms. Team sports, cycling, and other aerobic activity were particularly effective, especially if conducted for 45 minutes or more, greater than three times a week.

Randomised controlled trials have frequently shown exercise to generally be as effective as antidepressants in mild to moderate depression, but with less side effects. This won’t be the case for absolutely everyone with depression and some people will still need anti-depressants (there is no shame in needing medications for our health!), but exercise can have synergistic effects for people on antidepressants too.

So, we know exercise is good for mental health, but how much do we need to do? And what type?

The evidence suggests that the most effective type of exercise to improve mental health is aerobic exercise that is of moderate to vigorous intensity (think jogging, aerobics, swimming etc) of 30-45 minutes duration, performed on most days of the week. This could seem like a lot and even daunting to people new to exercise, but the good news is that even small amounts of exercise are very beneficial. A Brazilian study which looked at around 1000 people self-isolating during the COVID-19 pandemic, found that people who did just 15 minutes of vigorous physical activity a day, were 40% less likely to develop depressive symptom and 30% less likely to present with anxious symptoms! On the other hand, individuals spending more than 10 hours per day sedentary i.e. sitting/lying down, were 39% more likely to develop depressive symptoms.

These statistics are pretty powerful and demonstrate that when it comes to our mental health, exercise really is medicine.

Aiming to do something vigorous enough that you get out of breath is best, but even just a walk in the fresh air will be of benefit. Getting into the habit of regular exercise can be tough and it’s important to think of it as self-care which will improve your mental health rather than a chore. For people who are time poor, my personal favourite is finding a big set of outdoor steps and going up and down them for 15 minutes. Other tips include scheduling your exercise with a friend, buying new work-out clothes to help with motivation and most importantly, finding an activity that you enjoy!

Finally, although exercise is a wonder drug for our brain, it’s important to recognise that it’s only one part of looking after our wellbeing, and doesn’t take away from the need for reflection and discussion about what’s on our minds, rest and relaxation and seeking professional help when required.

If you or someone you care about is going through a rough time, seeing your GP is a great place to start or Lifeline can be contacted 24/7 on 13 11 14. Puke up https://puka-up.myshopify.com/, Beyond Blue, https://www.beyondblue.org.au/ , Black Dog Institute https://www.blackdoginstitute.org.au/ and Movember https://au.movember.com/ also have excellent resources to help you support yourself or a loved one get through a tough time.

Love Dr Izzy xoxo