We all fall. But while a tumble for a toddler is a learning experience, and a stumble for an adult is usually just embarrassing, for older people falls can be serious, even fatal.

In 2010, 13 million Americans reported being injured in a fall, often while walking on the pavement or up the stairs at home.

For those over 65, the figures are worse. One in three in this age group falls every year, resulting in about 250,000 hip fractures and more than 25,000 deaths, usually from traumatic brain injuries. The healthcare cost of treating these falls is estimated to be US$34 billion (S$46 billion) a year.

But if falling is such a common hazard, especially for older people, does that mean falls are inevitable? Is there nothing we can do about it - like improving our sense of balance?

Part of the challenge is that balancing is trickier than you think. Most of us are lucky enough that we rarely need to think consciously about it.

But try standing on one leg for 30 seconds - the way you might have to if a police officer suspected that you were drinkdriving.

Then close your eyes, and see how much harder it gets. That is part of a sideline balance test if you are a football or hockey player, and a trainer or doctor wants to assess whether you have suffered a concussion.

I discovered my own wobbliness a few years ago, while working on a magazine article about high-altitude hiking. Researchers had shown that the number of balance errors you make while holding a few simple 20-second poses - standing on one foot with your eyes closed, for example - can signal the onset of altitude illness.

I tried the tests and found that in the rarefied air of my Toronto office - elevation: 75m - I was as unsteady as a Himalayan hiker with mountain sickness.

As someone who exercises most days, I found this unsettling. What was missing from my regimen?

We have come to view fitness as a collection of discrete traits - muscular strength, aerobic endurance, flexibility and so on - that can be isolated, measured and tinkered with independently. The pitfall of that approach is: What is strength or endurance worth without the balance and stability to use them in the real world?

Simply staying upright is, in some ways, a full-body exercise. You have fluid-filled "organs of balance" in your inner ear that monitor the position and rotation of your head; and there are sensors known as proprioceptors in muscles and tendons throughout your body that detect subtle stretches and deformations. Your feet alone contain 11 small stretch-sensing muscles.

No matter how many calf raises you do in the gym, your balance will not be stable unless your brain is attuned to the signals from these sensors. Even wearing socks interferes with this subtle feedback and worsens your balance.

Walking is trickier still, since each step is essentially a controlled fall. Last year, researchers from Ohio State University showed that they could predict with accuracy where a walker's foot would land by looking only at the trajectory of the upper body during the previous stride. What seems like a simple act is actually a complex and near-instantaneous calculation that enables you to place your foot in exactly the right spot, to prevent you from falling on your face.

The current approach to this challenge is to add an additional box to check off: balance training. United States health guidelines already suggest balance training for older adults at risk of falls, and European countries like Austria, Ireland and Denmark recommend it for all older adults.

A step in the right direction, you might say, but it still presents balance as an isolated practice. The evidence is that a more integrated approach has greater benefits.

For an older adult who wants to continue living independently, the ability to rise from a chair and walk across the room, which requires the coordination of muscle strength, balance and aerobic activity, is more important than any individual element of fitness. And it is not just a physical challenge.

One key warning that you are at higher risk of falling is if you tend to stop walking when you talk - a sign that the cognitive demands of staying on your feet are overloading your brain.

An emerging body of research suggests that exercising in a way that taxes your coordination, agility and balance - a suite of abilities known as gross motor skills - rewires your brain in ways that are fundamentally different from straightforward aerobic activity or strength training. By improving these physical attributes, you also enhance cognitive performance.

One such study, published in 2011 by neuroscientists from Jacobs University Bremen in Germany, involved a year-long trial of 44 older adults that compared the effects of walking three times a week with what they called coordination training: a series of exercises using stability boards, balls, skipping ropes and other equipment, and including elements like "reaction to moving objects/persons".

Superficially, the two regimens were equally good. Compared with a control group that did stretching and relaxation exercises, both groups boosted their performance to a similar degree on cognitive tests, including measures of perceptual speed and executive control.

But what is interesting is that the cognitive gains occur in different ways, depending on the mode of exercise.

While aerobic exercise and strength training trigger brain chemicals that enhance neuron growth and survival, balance and coordination call on higher-level cognitive processes that seem to increase the number of synapses connecting the neurons.

That, in turn, suggests another reason simple balance exercises alone will not achieve what we want. It is novelty and unpredictability, rather than repetition, that are essential to keep your brain engaged.

A recent study by researchers in Denmark, Finland and Germany compared a group of 15 endurance-trained athletes, like runners and cross-country skiers, with a group of skill-trained dancers, gymnasts and figure skaters. The researchers captured data to assess their subjects' "motor cortex plasticity", a measure of the brain's ability to change its wiring in response to new stimuli.

Both types of athletes have highly trained calf muscles but endurance athletes use them repetitiously, in a way that the brain consigns to autopilot. Sure enough, plasticity in the area of the brain that controls calf muscles was no different between endurance athletes and non-athletes.

In contrast, the dancers, gymnasts and skaters, for whom autopilot is not an option, showed dramatically higher plasticity - their neurons were primed to keep learning new motor tasks.

A striking feature of the balance and coordination exercises used in these cognitive studies is that they sound a lot like games. Whether you are dancing or playing tennis, the unpredictability of your partner's actions means that no two workouts are the same. Perhaps the enjoyment we get from a good game isn't just a nice bonus. It is an indicator that we are fully engaged, mind and body, in the activity. You could call that achieving good balance.

NEW YORK TIMES