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How Old Is Your Body? Stand On One Leg and Find Out
According to new research, the time you can stand on one leg is the best marker of physical aging.

So I was lying in bed the other night, trying to read my phone, and started complaining to my wife about how my vision keeps getting worse, and then how stiff I feel when I wake up in the morning, and how a recent injury is taking too long to heal and she said — “well, yeah, you’re 44. That’s when things start to head downhill.”
And I was like “44? That seems very specific. I thought 50 was what people complain about”. And she said, “no — it’s a thing. 44 years old and 60 years old. There’s a drop off there.”
And you know what? She was right.
This study, published in Nature Aging in August of 2024 analyzed a ton of proteins and metabolites in people of various ages and found, when you put it all together, that there are some big changes in body chemistry over time — and those changes peak at age 44 and age 60. I should know better than to doubt my brilliant spouse.

But deep down, I believe the cliché that age is just a number. I don’t particularly care about being 44, or turning 50, or 60. I care about how my body and brain are aging. If I can be a happy, healthy, 80-year-old in full command of his faculties I would consider that a major win no matter what the calendar says.
So I’m always interested in ways to quantify how my body is aging, independent of how many birthdays I have passed. And, according to a new study, there is actually a really easy way to do this.
Just stand on one leg.
The surprising results comes from this study, appearing in PLOS One that analyzed 40 individuals, half under 65, half over 65, across a variety of domains of strength, balance, and gait. The conceit of the study? We all know that things like strength and balance worsen over time, but what worsens fastest? What might be the best metric to tell us how our bodies are aging?