As psychiatrists, psychologists and neuroscientists edge closer to a full understanding of how depression and anxiety prey on the human mind, excercise is increasingly being viewed as an invaluable weapon in the war against these damaging illnesses.

So, is it as simple as signing a bipolar-disorder sufferer up for a 12-month gym membership and waving them off, job done? Well, not quite – not yet, anyway.

With World Mental Health 2015 fast approaching (this coming Saturday, 10 October), we spoke with Professor Remco Polman, Head of Psychology at Bournemouth University, to discover the extent of what we know in 2015 about exercise being of benefit to the mentally fragile.

Hi Professor Polman. So, how much research has been done into the link between exercise and combatting depression? 

“There’s been a lot of research. Several systematic reviews have all shown that people who were depressed and engaged in physical activity found that their symptoms were lessened.

“But there are still a lot of questions to be answered, such as: How long should you exercise for? What types of exercise should you do? What level of intensity?”

And is research currently being done to get answers to these questions?

“Yes, there are constantly new research papers coming out and control trials being performed to further investigate the benefits of exercise.”

So are many doctors now advising potentially depressed patients to take up exercise, or is still a fairly unusual ‘prescription’?

Most doctors still won’t refer depressed patients into taking up some kind of exercise

“There are a couple of issues: firstly, most doctors still won’t refer depressed patients into taking up some kind of exercise; secondly, one of the symptoms experienced by depressed people is that they don’t really want to engage in anything, so it can be to hard to get them to do physical activity. And we haven’t really found a solution for that yet.

“Another issue is that some of the medications used by people with mental disorders can further decrease the will to perform physical activity, and some medications can induce weight gain as well. So it can become something of a vicious circle.”

So exercise isn’t currently being viewed as an alternative to medication, more an add-on to it?  

“At the moment, yes. Medical professionals here in the UK aren’t yet able to refer patients to fitness professionals. But in New Zealand, for example, patients can be referred to fitness experts who are specially trained to assist them in starting up an exercise programme.

“We often think that people will just somehow ‘know’ how to exercise – but really, most people have no idea.”

Are there any specific mental disorders that exercise is particularly effective against? 

“It’s definitely effective against depression and anxiety, and there have been some studies done with bipolar disorder patients which have generally shown exercise to be beneficial.

Exercise produces endorphins within the brain, which make people feel ‘better’

“The underlying thing with all these disorders is that exercise produces endorphins within the brain, which make people feel ‘better’. There would appear to links between endorphin deficiencies in the brain and depression, anxiety and other mental disorders, although it’s hard to conclusively test that.”

So there’s not one particular kind of exercise that’s proved itself to be the most effective in battling depression? 

“Well, I’d advise moderate exercise, by which I mean you’d still be able to talk to a person next to you. If you’re running or walking or cycling, generally 30 minutes should be sufficient. However, some recent research has shown than patients may feel benefits after just 10 minutes.

“But then, if you exercise for 10 minutes, you may only feel the effects for an hour afterwards; exercising for 30 minutes, however, you may feel the benefits for two or three hours.”

“My personal recommendation would be: do 30 to 40 minutes exercise, at moderate intensity –and make sure it’s an activity you actually enjoy. That’s very important.

Build your exercise up so that you’re not put off straight away

“I’d also advise people to get some kind of professional to guide them at first. You can’t really go from no exercise straight into performing 40 minutes of exercise – that’s going to hurt. You ideally need to build your exercise up in a systematic way, so that you’re not just in pain for a week afterwards from doing too much, and you’re then put off straight away.”