Standing the Test of Time: What a One-Leg Balance Test Reveals About Aging

A recent study out of the Mayo Clinic caught my eye. Researchers there took the measure of 40 healthy adults over the age of 50 to get a more precise read on when our functional physical capabilities decline with age. They looked at the classic things that gerontologists look at, leg strength and walking/gait for instance. But when they compared the seniors to the middle agers, what jumped out was a precipitous decline  in balance, which they measured by timing their subjects’ ability to balance on one leg. The drop was most dramatic standing only on the non-dominant leg. (The subjects didn’t have to do anything acrobatic with the dominant leg – as long as it wasn’t touching the ground.) Balance, for the Mayo group, was the most sensitive barometer of overall aging, capturing changes that had, or would have, the most profound effect on people’s everyday life.

So, where does that leave us? Or, for that matter, me? I’ve got skin in the game. Eighteen months ago, I had surgery for spinal stenosis bad enough that I couldn’t walk for more than 10 yards. The procedure was very successful, I’ve returned to my resistance training regimen and my muscle strength is nearly what it was before the procedure. But I am aware that my balance is still wanting. I find that I’m a bit more tentative when moving down steps or pivoting while moving than I was before the surgery. Upon testing, I find that while my dominant one-leg standing time is better than average, my non-dominant leg time is considerably lower.

So, no question, balance is hugely important. A whole body of research tells us that a drop in the ability to stay comfortably upright, especially moving over uneven ground, is a kind of “canary in the coalmine,” alerting us to potentially life-changing physical problems down the road. The epidemiological evidence tells us that the worse you score on a balance test, the higher your risk of dying in the coming years, from any cause. Consider a single study out of Brazil that looked at 1,700 older adults. Fully 20% were unable to balance on one leg for at least 10 seconds. That group had double the risk of dying within ten years. 

The straightest line between poor balance and a shorter life is falling, poor balance being the number one reason for seniors taking falls, the most common cause of serious injury in later life. But poor balance is also part of a larger downward spiral that can, and will if we live long enough, bring us to frailty. Just to take one example: if you lose confidence in your ability to move through the world, you become more sedentary, putting you at greater risk for heart disease and just about any chronic “disease of aging” you can think of.

My longevity medical practice is built on “biomarkers of aging,” namely  the idea that if we can measure something precisely, we’ll have the information at our fingertips to shore up our vulnerabilities. So, is there a “Balance Age” to help us gauge our efforts to live our healthiest, and perhaps longest, life?

Sort of. That simple standing-on-one-leg test is a very good functional measure of balance. Experts in the field suggest some parameters here. According to a Duke study, people in their 30s and 40s could stand on one leg for almost a minute; people in their 50s, for about 45 seconds; in their 70s, for about 25 seconds. I regard those numbers as baseline minimums – I’m sure most of my patients would do considerably better. But it’s a starting point.

A major bonus here is that the functional test doubles as a training regimen -- the more you practice standing on one leg, the better you get at it, the better your balance. (Of course, there are other more demanding or interesting exercises that build balance. A recent New York Times article ticks off five, including the venerable one-leg body squat: https://www.nytimes.com/2025/02/22/well/move/balance-exercises-aging.html  ) I should add, that’s often not the case with functional tests. My pulmonary function test (from which I derive a “Pulmo Age”), measuring maximum exhalation in one second, delivers data that corresponds very well with lifespan –the better the lungs, on average, the longer the life. But there is no specific exercise that will improve lung function. Grip strength is another example, a good proxy for overall body strength. But if you exercise on a grip strength trainer device religiously, you may develop the grip strength of a 25-year-old but you won’t meaningfully have increased your overall strength or, likely, your lifespan.

The beauty of a simple balance diagnostic test is that it captures, in a single output, so much complicated physiology: how our vision, our inner ear balance (the “vestibular” system), our musculoskeletal system and the nerves distributed throughout our body come together to keep us upright and moving. Not only are there so many parts, but every part is potentially subject to damage from so many directions, garden-variety age-related wear and tear, but also arthritis, a handful of common medications, and often progressive cardiovascular and neurological issues.

That all adds up to a massive challenge if we’re trying to get “under the hood” and measure how the different parts of our balance mechanism are aging. In recent years, much of the intellectual energy in the longevity field has been aimed at measuring changes in the epigenome that give us a picture of aging at the deepest level, in some cases, organ system by organ system. Where to begin with balance? 

But we do have, potentially, a glimpse into the future, a pilot study looking at tai chi, a practice that addresses balance from multiple therapeutic angles, including breathing, mental focus and muscular strength. The study found that middle-aged and senior women who did tai chi had changes in their epigenome, that is, the chemical markers that regulate gene expression. These changes, specifically to methylation patterns, suggest that the practice could buffer changes in the epigenome that might translate to healthier gene expression, and healthier aging. We don’t know exactly what’s going on at the macro/organ level but a number of studies have measured improvement in strength, flexibility, cardiovascular fitness and immune response. That comports with other research that showed that a tai chi regimen reduces falls in seniors, in one study in The British Journal of Sports Medicine, by some 47%, as well as a literature of research suggesting exercise in general has a positive effect on epigenetic aging.

So, I am working on balance exercises daily and maintaining optimal hormone levels to allow for the maximal benefit from this training. And I hope that within the next 6 months I’ll post a video of me standing on one leg for a full minute!   

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Rezaei A, et al. Age-related changes in gait, balance, and strength parameters: A cross-sectional study. PLoS ONE 2024. 19(10): e0310764. October 23, 2024. https://doi.org/10.1371/journal.pone.0310764

Claudio Gil Araujo et al. Successful 10-second one-legged stance performance predicts survival in middle-aged and older individuals. Br J Sports Med.2022 Sep;56(17):975-980. doi: 10.1136/bjsports-2021-105360. Epub 2022 Jun 21

Hua Ren et al., Epigenetic Changes in Response to Tai Chi Practice: A Pilot Investigation of DNA Methylation Marks. Evid Based Complement Alternat Med. 2012 Jun 5;2012:841810. doi: 10.1155/2012/841810

Cathie Sherrington et al. Exercise for preventing falls in older people living in the community; an abridged Cochrane systematic review. Br J Sports Med. doi.org/10.1136/bjsports-2019-101512