Body & Fitness

Working out for the body and brain

Renowned neuroscientist Wendy Suzuki was at a profound low point, with no life outside work, when she discovered that a workout for the body and brain can have some surprising results.
Wendy Suzuki: “If you move your body, you will change your brain.”

It all started for Wendy Suzuki as she turned 40. A renowned neuro­scientist, she was running her own research lab at New York University where she had earned tenure as a professor. On the face of it she appeared to have achieved everything she had worked so long and hard for. And yet one day she woke up and decided she didn’t have a life. “I was at a profound low point,” she says.

The reality was Suzuki had no friends outside her job and no partner; all she ever talked about was work because she had nothing else going on. And she was 10 kilos overweight. “It seems I was really good at engaging with science and advancing my career, but really bad at living.”

So Suzuki became her own experiment and in the process got thinner, happier and smarter. What’s more, transforming her life and boosting her own brain power prompted a change of work focus that has opened up an area of scientific research she believes could have huge benefits for both our productivity and our joy.

For a start, she realised large parts of the motor areas of her brain were not being used because her lifestyle was so sedentary. And the areas involved in non-science creativity and such things as meditation and spirituality she describes as being like “barren deserts”. Suzuki details what she did about this, and the science behind it, in a new book, Healthy Brain, Happy Life: How to Activate Your Brain & Do Everything Better.

Her first step was to improve her physical fitness. She’d had a wake-up call on a rafting trip on the Cotahuasi River in central Peru. “That was the key moment that made me literally run to the gym,” she recalls. “Every­one else on that trip was stronger than me, and I realised something was really wrong. So the day I got back, I signed up to a gym, and I stuck to it because I didn’t want to be the weakest one on a trip ever again.”

Initially, she worked with a personal trainer and took a few group classes. And then she discovered “a workout with a message” that she credits with being the catalyst for eventually shifting her neuroscience research. Called intenSati, it involves doing movements taken from kickboxing, dance, yoga and martial arts while shouting positive affirmations along the lines of “I am strong now”, “I am inspired” and “I believe I will succeed”.

Suzuki says this sort of “intentional exercise” is a workout for both body and brain. Although popular in New York, it hasn’t taken off in New Zealand yet, perhaps unsurprisingly since as a nation we’re generally shy of anything we think might make us look silly.

“I totally felt silly the first time,” she admits. “I kind of mouthed the affirmations until I realised they increased the cardiovascular workout. And actually you get over the silliness factor pretty quickly. You’re doing it in a group, and replacing negative thoughts with positive ones so it’s like a mantra.”

“That’s when it really struck me that with the exercise I was able to focus my attention for much longer.”

Improving memory and mood

Predictably, Suzuki began to get fitter and shed the kilos, but it was a more unexpected change that interested her most: a beneficial effect on her memory and mood.

“It didn’t happen overnight, but about a year and a half later I was in a big cycle of writing grant applications and that’s when it really struck me that with the exercise I was able to focus my attention for much longer on the writing process. I was reading a lot of papers and bringing together various points and found I could remember details better.”

Curious to discover what might be going on, Suzuki looked back over the available research to find out what was known about aerobic exercise and the brain. “At that point my interest was in myself. I wanted to know if I could get even more improvement. What was the maximum?”

What Suzuki discovered was that most of the neuroscience studies looking at exercise had involved animals. A lot of what we understand comes from research looking at the brain changes in rats raised in enriched environments. These rats get to live in a kind of rodent Disney World with colourful toys and lots of space and other rats to engage with.

Early experiments of this kind in the 1960s debunked the idea that the brain was a fixed thing that couldn’t change. The Disney World rats had brains that were physically larger than those living in what researchers called impoverished environments. Their dendrites – the input structures of the brain – had expanded, allowing the cells to receive and process more information. Plus there were more synaptic connections, meaning better communication between the cells of the brain, more blood vessels and higher levels of particular neurotransmitters that have a role to play in memory and learning, as well as a protein called brain-derived neuro­trophic factor that supports the survival of cells during brain development and in adulthood.

This study proved what Suzuki refers to as the “everyday, beautiful plasticity of our brains”, how everything we do in our life shapes and changes the brain, developing an increasing amount of neural connections the more enriched our environment and experience is.

What caused the brain changes

Further research pinpointed exactly what it was about the rodent Disney World that was causing all these striking brain changes. What most contributed was exercise. Rats that ran on a wheel performed better in a wide range of memory tests. Exercise alone doubled the rate of the birth of new neurons, the workhorses of the brain, in the hippocampus, which is known to be crucial for long-term memory, learning, creativity and mood.

So good news all round for the rats, but when Suzuki looked into research with the human population, she realised it was mostly limited to school-age children and the elderly. Although the results were encouraging, showing physical exercise strongly correlating with brain health and significantly reducing the risk of developing dementia, very little work had been done looking at the effects of exercise on the brain function of healthy adults, possibly because they are viewed as being at the height of their brainpower with little room for improvement. But if that was the case, asked Suzuki, why had she noticed such an improvement in her grant-writing skills after embarking on a regime of regular exercise?

The bright idea

That’s when she had her bright idea. She decided to create a new neural science course that brought exercise into the classroom. Her students would examine the positive effects of exercise on the brain while experiencing it themselves.

Type A to the very last, Suzuki trained as an intenSati instructor so she could teach every aspect of her new course, which involved 20 students taking part in a weekly hour of exercise followed by three minutes of meditation and then a lecture. “I’m lucky that I’m in a department where I’m given a lot of freedom. This was an unusual class and it caused a lot of noise as the music was blaring. But I think the only serious concern the education committee had was whether the room was going to be smelly afterwards.”

Suzuki was excited because she would be giving her students the unique experience of being both the subjects and the experimenters, and they’d get to analyse their own data. “Frankly, I didn’t think we’d see much [difference] from a group of 20 healthy students exercising only once a week. But we did. I found my students improved their reaction times – they were faster at answering questions than the group that didn’t exercise. That told me I was onto something.”

Further work with patients who had suffered traumatic brain injury showed that exercising twice a week for eight weeks in a group improved four measures of their mood and well-being.

Suzuki is now involved in a larger study comparing adults aged 35 to 59, with one group randomly assigned to taking three classes of Spinning – a highly aerobic form of indoor cycling – a week and the other to playing brain-boosting computer games. Next year she has a study lined up in which she’ll work with 80 freshman students. “They’ll do a semester with no exercise and then one with exercise to see how it improves things like cognitive performance, mood and memory.”

The ultimate goal is to involve functional magnetic resonance imaging, which can detect changes in blood flow in the brain and is the most common tool used to measure brain activity. That way she’ll see more clearly what effect exercise is having on the different parts, and therefore specific functions, of the brain.

For instance, the frontal lobe is integral to working memory, planning and social behaviour; the amygdala is all about emotions; and the striatum is part of the reward system. Studies show that once we reach adulthood, there are only two areas where neurogenesis (the birth of new cells) can occur – the hippocampus and the olfactory bulb, responsible for our sense of smell.

We know that the hippocampus is important for making our memories stick, thanks to the study of an unfortunate young American known as HM who, in the 1950s, had such severe epilepsy he agreed to experimental surgery to remove the hippocampus on both sides of his brain. Although his intelligence remained high, he was left with an inability to remember anything that had happened to him after the surgery. So he could remember his childhood home but not how to get to the bathroom in the hospital.

For ageing and increasingly more obese Western populations, Suzuki’s research has huge significance. Can exercise keep the hippocampus firing better for longer? If so, how much physical activity must we do to get a few more good years from our brains later in life? And what type is best?

Suzuki doesn’t have the answers yet but she believes they are coming. “I hope that in 10 years maximum, maybe five, I will have a handle on it.”

In the meantime, she continues to exercise four or five times a week and teaches a regular free class at the university. “It’s important to vary your workouts to challenge your motor system. Keep a good amount of aerobic exercise but quieter activities like yoga and meditation too. And start stretching your brain in other ways.”

“Better than crosswords & Sudoku”

In Healthy Brain, Happy Life, Suzuki supplies a series of four-minute “hacks” to enrich and expand the brain – many of which involve music – shown to activate areas involved in reward, motivation, emotion and arousal. In particular she encourages new experiences. She is not, however, a huge fan of the brain-game industry.

“It doesn’t have as much science behind it as exercise does. People will get better at the games if they want to but it’s not clear how much it helps. Crosswords and Sudoku puzzles don’t have much evidence for them either. Doing one is better than sitting and watching TV, but is it going to grow your brain and cause significant plasticity? Exercise is better.”

One thing that has been proved is that exercise helps reverse the damage caused by one of the brain’s big enemies – long-term stress. Stress releases the hormone cortisol, as part of our fight or flight response. But prolonged high levels of cortisol are bad for the hippocampus, which is endowed with a large number of receptors for the hormone. It can even start to kill the hippocampal cells, shrinking the area, impairing both learning and long-term memory.

Rat stress tests have demonstrated exercise’s protective powers – putting in some time on that running wheel helped the rodents reduce anxiety and improve memory function, and it stimulated the growth of new cells.

“If you move your body, you will change your brain,” says Suzuki, who maintains that exercise has enhanced her mood, learning, memory and attention and improved her creativity. She has combined it with meditation, also shown by science to produce positive brain changes, saying she feels calmer and more able to cope with everything that comes at her. But most importantly, as her brain has improved, so has her life. She now has a social life, goes out on dates, is healthier and happier.

“When I started out, I had no idea what was going to happen. I was just trying to deal with some things that were wrong in my life. But my relationship with myself changed when I started to pay attention to the mind-body connection. I’m in a very different place now at 49 than I was at 40.

Healthy Brain, Happy Life: How to activate your brain & do everything better, by Wendy Suzuki (William Heinemann, $40).

Brain hacks, clockwise from top left: visual cortex (Portrait of the Artist as a Young Derelict by Jean-Michel Basquiat); invention; cognitive; creativity (Lorde); auditory cortex (Pharrell Williams).

Brain Hack

  • Creativity brain hack: Make up new lyrics to one verse of a favourite song.

  • Invention brain hack: Think of two ideas to make your workday more efficient. You might rearrange your desk or try rearranging the order in which you tackle tasks.

  • Cognitive brain hack: Go online and teach yourself a new dance move from the So You Think You Can Dance website, then practise it for four minutes.

  • Visual cortex brain hack: Find a new piece of art online and get lost in it visually for at least four minutes.

  • Auditory cortex brain hack: Listen to a popular song from a genre of music you never listen to or in another language. Try to understand why it might be so popular.

Photos by Getty Images

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