FEW things in life are as embarrassing as falling flat on your face in public. Thankfully, once we have grown out of racing around in parks and playgrounds, it doesn’t happen all that often.
Don’t take your grace and poise for granted, though. According to a growing body of research, our ability to balance – one of humanity’s hardest-won evolutionary skills – is beginning to fade away. Around the world, falls that lead to serious injury or death are on the rise, even in the young. And most of the time, the people falling over are sober and doing nothing more complicated than standing or walking.
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Globally, falls are the after traffic accidents. Between 1990 and 2017, the Risk of losing your balance increases with age, so you might think this simply reflects the huge number of baby boomers entering their twilight years. But recent estimates suggest the incidence of falls is rising at a rate that .
So what is happening? The decline in our collective stability is prompting scientists to take a closer look at the complex brain-body interactions that underpin our ability to balance, and the ways that it is tied to both cognitive and emotional processing. This system is remarkably complicated, but it turns out that the problems undermining it are relatively simple to pin down. That means there are little things we all can do to improve our balance and reduce the risk of falling.
Anyone who has unintentionally hit the deck of late can take comfort in the fact that bipedalism is far from easy – particularly the way people do it, with our torsos balanced precariously over our legs. In fact, this is such a precarious way of getting from A to B that we are the .
The human body, when standing upright, is inherently unstable, says at Ohio State University’s Movement Lab. Our bodies are top-heavy, with a tiny base of support relative to our height. Worse, our centre of gravity sits way up at pelvis height and slightly forward of our ankles. Even without a heavy head and chest swaying around, standing up would be risky.
When in good health, we manage it by using a vast brain-body network which integrates information from our muscles, eyes and the vestibular system of the inner ear. It then engages muscles of the legs and core to make necessary adjustments to posture. While the core muscles often get the credit for keeping balance, it is the leg muscles that do most of the work. “If we turned off all our muscles in our legs when we were standing, we would fall,” says Srinivasan.
Integrating constantly changing information coming from the muscles, joints, senses and the environment is a massive computational challenge, and neuroscientists don’t fully understand how the brain accomplishes it. They have identified a few key players, however. Perhaps the most important is the cerebellum, the small, bulbous region at the bottom of the brain that contains more neurons than all other brain areas combined. Evolutionary studies have shown that it rapidly increased in size as our ancestors began walking on two feet (see “On your feet!”).
It is thought that our ability to rapidly react to different situations is thanks to the brain making predictions based on previous experience. Some neuroscientists have suggested that The area is linked with other brain regions including the motor cortex, which directs movement, in closed loops that shoot information back and forth. The cerebellum acts as a kind of super-fast processing outpost that supports all other operations, says cognitive neuroscientist at Texas A&M University. “You send stuff back there to process it more efficiently and it also brings information forward and helps you refine your behaviour.”
The link to mental health
Anxiety, depression, schizophrenia and other mental health disorders in a way that influences both standing posture and gait.
Ron Feldman at Tel Aviv University in Israel says there are many potential reasons why. People with depression tend to have a more stooped posture with significantly slower movements. This increases the risk that, if they stumble, any righting movements will happen too slowly. For people with schizophrenia, symptoms of mental distress are often accompanied by a swaying posture, which has been linked to problems with integrating visual information with other components of balance. For those with anxiety, fear of falling can, paradoxically, affect posture in such a way as to make a fall more likely.
Yet this new understanding hasn’t translated into new methods of diagnosis or treatment so far. “The physical elements are usually not addressed in mental disorders,” says Feldman. That may be a missed opportunity, he says, because the relationship between balance and mental health might go both ways; work to improve your balance could benefit your mental health too.
Having a wobble
We have long known that the cerebellum plays a part in movement control. More recently, research has shown it has a role in fine-tuning our thoughts and emotions too. This could explain why some mental health conditions also commonly feature poor balance (see “The link to mental health”). It could also explain studies in which people who are asked to do a cognitively demanding task don’t balance as well at the same time, and those trying to balance do worse in cognitive tasks. It turns out that it might be quite apt when people invoke the language of balance when describing feelings, such as feeling emotionally “stable” or “having a wobble”.
Walking seems effortless to most people, so Srinivasan was surprised by what he found when he looked a little closer. He and his colleague , also at Ohio State University, and used an infrared camera to track their movements while they walked on a treadmill. They found that, even on a stable surface, walking is basically a refined version of a drunken stagger or a stumble after an unexpected nudge. “Imagine you are walking along and you get pushed to the right. Naturally you would stick your right leg rightwards and apply a leftward force,” says Srinivasan.
It turns out that every step, even on the smoothest surface, is a process of re-righting ourselves as our upper bodies lurch from side to side. Usually, we don’t look as if we are staggering thanks to the way that the cerebellum, senses and muscles work together to make micro-corrections mid-stride. Srinivasan’s studies revealed that this is largely because the brain keeps tabs on the position of the pelvis and adjusts the leg position accordingly. Srinivasan says we step, not towards where we want to go, but “in the direction of where we are falling”.
“Walking is basically a refined version of a drunken stagger”
Because the body’s balance-control system is made up of so many interconnected parts, it can be challenged in many different ways. Uneven ground, a problem with the vestibular system, weaker muscles or greater speed can make it more difficult to keep upright and can turn a wobble into a fall. Pregnancy, illness and injuries – particularly to the legs – are among the things that can affect the inputs into the system enough to make a fall more likely. Inflammation, which is linked to obesity, stress, injury and infection, has also been shown to , potentially increasing the risk of falls.
When people’s balance is tested by asking them to stand on one leg with eyes open or closed, it reveals that the ability to maintain our equilibrium . By midlife, there is an increase in the likelihood of serious falls. That seems to be getting worse. One analysis has found that fatal falls for people in the US aged between 45 and 64 . This increase has researchers scrambling to figure out which aspects of this complex system are getting out of sync.
The first problem, says Dawn Skelton at Glasgow Caledonian University, UK, is that children aren’t moving enough. Our stability is built up by trial and error as we learn to walk, gradually refining a toddle into effortless striding and running. The more this system is challenged in childhood and early adulthood, the more reserve we have to draw on in later life. Too much sitting, cuts in school sport and shorter break times mean that young adults are hitting their 20s with a wobblier stance than they should, says Skelton. From there it is all downhill. These same factors mean the muscles we need for balance are weaker than they should be. According to one recent study, 10-year-old children in England in 2014 were .
Through midlife, sedentary lifestyles become even more common, leading to a drop in strength that can make falls more likely. The trend towards sitting for longer probably accounts for some of the rise in falls in younger adults too. According to , millennials – those who reached adulthood around the turn of the century – are significantly weaker than adults of the mid-1980s. A general lack of fitness hammers in the final nail: when we do less physical activity, the balance system is left unchallenged, getting less effective by the day.
On your feet!
Early humans, we always thought, first struggled onto two feet after a long period of gorilla-like knuckle-walking. But a newer hypothesis suggests that our move to bipedalism , at a time when our ancestors were still living in the trees.
According to this line of thought, about 15 million years ago, our tree-dwelling ancestors began to spend more time standing up, at first holding onto branches with their hands and gradually balancing independently. One study found that even lightly touching a moving branch with the fingertips . If this is true, then learning to balance is an integral part of what made humans what we are today.
All of this adds up to a perfect storm of falling younger. “I commonly see people in their mid-40s that have worse balance than 70 or 80-year-olds,” says Skelton. Research on falls used to focus on people aged 65 and up; studies now report on falls in 50-year-olds.
Walk the line
Age-related declines in brain function really start to show at about the age of 50, says Bernard, and the cerebellum is one of the first regions to go, particularly in women. We don’t know exactly how or why this happens, but we do know that oestrogen has a protective effect on the brain and declining levels of the hormone during the menopause might be part of the answer.
Fortunately, there are steps we can take to slow or even reverse this decline (see “How to restore your balance”). Balance training, which can be as simple as standing on one leg, sitting on a balance ball or practising walking heel-to-toe along a line on the floor, has been shown to bring improvements in , and in those with .
As if to underline the “use it or lose it” nature of balance, the more work you do on your balance, the greater the improvement. The dose required for older people is around double that for the under 40s. One study found that, to see a noticeable improvement in their balance, , whereas people under the age of 40 needed only 16 to 19 sessions of 15 minutes. What’s more, balance and strength training can help reduce the fear of falling, which encourages further exercise, setting up a virtuous circle of improvement.
As well as physically training the balance system, there is intriguing evidence that engaging in cognitive challenges might help. This may work by engaging parts of the brain responsible for motor function and other complex tasks that are linked to the cerebellum, and by reducing the cost of thinking while walking.
“Young adults are hitting their 20s with a wobblier stance than in the past”
The cerebellum operates on the same use-it-or-lose-it basis as the rest of the brain, so the most important thing is to give it something to do. In one study, people who did 100 days of cognitive training over a six-month period than those who didn’t. “Using your resources can be beneficial in terms of maintaining function,” says Bernard.
If physical and cognitive training are good in isolation, doing both at the same time is even better. Tai chi, which involves focused attention and a series of fluid physical movements, has been and reduce the fear of falling, the number one risk factor for falls.
The good news, says Skelton, is that there is no need to enrol in any specific balance-related programme. “If you want to stop the rot, you don’t have to go and do a structured exercise programme,” she says. “Just any activity that challenges you to stay upright.” Whatever your age and ability, the time to start is now.
How to restore your balance
Want to boost your balance? First, test it out. If you can’t stand on one leg with your eyes closed for at least 30 seconds, says Dawn Skelton at Glasgow Caledonian University, UK, you should start balance training as a priority.
Standing on one leg is a good measure of balance skills because it taxes the balance system as a whole. The eyes-closed version of the test is particularly revealing because it takes vision out of the equation, showing how your muscles and the vestibular system of your inner ear alone cope with the challenge of staying upright.
“If you stand up and close your eyes, you will feel that the wobble happens in your ankles and feet,” says Skelton. She suggests practising rocking forward and back between the heels and toes and also foot strengthening exercises, such as picking up a marble or pen between your toes. It is surprising how many people can’t manipulate their toes, she says. Going barefoot indoors and wearing minimal shoes can also help keep the feet fit and strong, she says.
Skelton doesn’t rate pilates or slow-moving kinds of yoga as ways to improve balance. They are great for core strength and can also build up leg muscles in a way that improves standing balance, she says. But because they mostly involve assuming still postures fairly slowly, they don’t tax the body’s ability to combine sensory information from the eyes with internal sensations coming from the vestibular system of the inner ear. “Eyes open, head moving: that’s what trains your vestibular system,” says Skelton.
Hit the trail
This means that gym bunnies who train inside on static bikes and treadmills aren’t doing their balance skills any favours. In contrast, road cycling and mountain biking involve balancing while looking around for cars or trees, looking straight ahead on a static bike doesn’t. Similarly, running outside involves dodging pedestrians and negotiating uneven ground. Running while staring at a screen at the gym, less so. The need to resist gravity also has to be a factor in any balance-training exercise, adds Skelton. That is why swimming isn’t especially good for balance, despite the fact that you need to turn your head.
If you want to start simple and be sure that what you are doing will benefit your balance and reduce your risk of falls, the UK’s National 91ɫƬ Service , crossing your feet as you do so, or standing on one leg with or without your eyes shut. Hold onto a wall for support until you are sure you won’t fall. For the more acrobatic, practising standing and moving on a wobbleboard, doing slalom walks on stable and uneven surfaces and balancing on beams or logs can take things to another level.
