Physical activity is good for you in lots of ways, so why do so many people not get enough?

The evidence is overwhelming: exercise is good for you. Not just physically, but also mentally. Exercise reduces depression and anxiety. It boosts your memory. It protects against disease.

I’ve just read a new book, Move! by Caroline Williams, that tells about some of the latest research on the benefits of physical activity. More on that in a moment. First, a few observations.

Working in universities for many decades, I’ve met numerous smart people, including some who think highly of their own intellects. After all, one of the few talents that academics have more than others is using their minds to extend knowledge. Yet if academics are proud of their mental capacities, and seek advancement in their careers depending on the outputs from their intellectual prowess, why do so few take heed of the evidence that physical activity protects the mind and boosts mental performance?

            There are several possible explanations. One is a persistent belief that the mind is pretty much independent of the body. Another is that using your body is lower in status than mental work. This is why, if you’re going to exercise vigorously, do it in a gym where you have to pay, not out in public. Driving a car is more dignified than walking to work.

A third explanation is that our lifestyles are designed to discourage exercise. More on that later.

Move!

Caroline Williams is a science writer. She interviewed scientists researching how the body affects the mind, and weaves what she has learned into an engaging account, adding comments drawing on her own experiences. If you need convincing that movement is good for you, Move! is a good place to start.

            The book is more than a motivator. Williams tells how different sorts of movement affect different aspects of mental performance, including creativity. She starts by telling about human evolution and how movement and mental functioning are intertwined.

“… our biological baseline is to be on our feet, moving and thinking at the same time. If we don’t do it, our brains make the sensible decision to save energy by cutting brain capacity. In better news, when we get on our feet and move, it primes the brain to be alert and to learn.” (p. 32)

This reminds me of research I read about years ago saying that the brains of people over age 50 start to shrink — except for those who exercise regularly. Use your body or lose your mind.

Williams reports on research about physical activity and rumination, which is repeatedly and unproductively thinking about things in the past. The more you ruminate, the less happy you’ll be. Here’s a surprising finding. When you are moving, walking or jogging, you are literally putting things behind you, and this sense of forward movement reduces rumination and hence is good for your mental health. This made me wonder whether walking outdoors is superior to walking on a treadmill, because with a treadmill you remain in the same place. Maybe you still feel you’re moving forward, especially if you watch a screen showing scenery going by.

            As well as moving, it’s also valuable to build your strength. Having stronger muscles leads to a longer life and makes you feel better too. You don’t need a physique like Arnold Schwartzenegger’s: you can be stronger without any increase in muscle size. There are mental benefits too. Williams states:

“There is also a link between bodily strength and a healthy brain. A ten-year study of twins showed that greater strength in middle age is linked not only to more grey matter but also to a better functioning memory and a quicker brain a decade later, while grip strength (an overall indicator of muscle power) is associated with a healthier hippocampus.” (p. 57)

Many people think muscle-builders are less intelligent than weedy types who spend their days reading. This needs to change. Having strong muscles and flexing them regularly is a good way to enhance brain power and creativity.

To get moving is good. To do it in rhythm is even better, certainly for mental functioning. Dancing is one option. Another is an exercise class, accompanied by energising music.

            Moving together with others dissolves the sense of self, so you feel part of the group. Williams notes that you need to be careful about this. The Nazi salute and mass rallies helped to bond the German population with Hitler.

“Sit up straight!” Did your parents ever tell you this? Slouching may feel more comfortable, but there’s solid scientific evidence about the physical and mental benefits of good posture. Sitting or standing straight is linked to having positive thoughts. More generally, using core muscles is good for controlling stress. Options include running, Pilates and yoga. Strangely, using core muscles is calming.

            Stretching is good for you too. If you’ve been sitting for a while, it’s beneficial to get up and stretch. Williams delves into the advantages and disadvantages of stretching beyond what the mind says is too far, and the challenges for those who have hyper-mobile joints.

Then there is breathing, normally an automatic activity but one that can be the focus of attention. Williams tells of research on breathing six times per minute, a process that stimulates the vagus nerve and calms the body.

Barriers to physical activity

Given decades of research showing the physical and mental benefits of physical activity, you might think that everyone would be going out of their way to keep active. Alas, only a minority do, and those who are older and need it the most are the least likely to move enough for optimal mental and physical health. Why?

The main problem is that humans have constructed environments for themselves that make it too easy to be lethargic, at all ages. Think of “labour-saving” devices. Think of cars, ride-on mowers, video games, Facebook. Think of parents protecting their children by driving them to school.

In the book The Energy Glut, Ian Roberts says cycling to work is dangerous but it’s even more dangerous not to cycle to work. In other words, the health risks from not getting exercise are greater than those from commuting by bicycle.

            In Australia and many other countries, cities are constructed in ways that discourage everyday walking and cycling. There are vast car parks around shopping centres and just a few places for bicycles. Imagine an alternative urban design, closer to that in Amsterdam, that makes it easy and attractive to walk and cycle, and makes it slow and inconvenient for drivers.

Unfortunately, most of us live in what is called an obesogenic environment, one that discourages activity and encourages overeating. Although it’s possible to go to the gym or participate in sports, the trouble is that this requires initiative. A society that prioritises movement would design the physical environment and incentives so that being active would be the easy option and sitting for hours on end was considered foolish.

We can dream about an alternative society, but until things change it is mostly up to individuals to do what they can in their personal situations. So read Move! and be inspired. And while you’re reading it, remember to occasionally get up and stretch.

Caroline Williams

PS Some earlier accounts that I’ve found useful.

John Ratey with Eric Hagerman, Spark: The Revolutionary New Science of Exercise and the Brain (New York: Little, Brown, 2008)

Ralph S. Paffenbarger, Jr. and Eric Olsen, LifeFit: An Effective Exercise Program for Optimal Health and a Longer Life (Champaign, IL: Human Kinetics, 1996)

Roy J. Shephard, Aging, Physical Activity, and Health (Champaign, IL: Human Kinetics, 1997)

Thanks to Tonya Agostini, Julia LeMonde, Monica O’Dwyer, Tim Johnson-Newell and Jody Watts for helpful comments.

Brian Martin
bmartin@uow.edu.au