Bryan Johnson shares a simple test you can do anywhere to figure out your biological age

Bryan Johnson instructs The Long Play attendees on a simple longevity test. Nina Menconi for Nikki Ritcher 2026-04-15T04:04:36.561Z Share Copy link Email Facebook WhatsApp X LinkedIn Bluesky Threads lighning bolt icon An icon in the shape of a lightning bolt.

Impact Link Save Saved Read in app This story is available exclusively to Business Insider subscribers. Become an Insider and start reading now. Have an account? Log in. Bryan Johnson shared a simple longevity test at a Business Insider event. The longevity entrepreneur says the one-leg balance test indicates biological age. A small Mayo Clinic study supports one-leg balance testing as a measure of frailty in older adults. AI-generated summary Summaries are generated by an AI model trained on Business Insider's articles. AI may make mistakes or provide inaccurate/incomplete information. We're unable to load that answer right now. Please try again. What inspired Bryan Johnson's longevity test? What are alternative measures of frailty? What are the limitations of balance tests? How does the one-leg test assess biological age? How reliable is the balance test for longevity? As a multi-sport athlete, I track my fitness through swim time trials, burnout lifts, and functional threshold power evaluations that push me to my mental and physical limit. Loading audio narration... Bryan Johnson, the 48-year-old entrepreneur obsessed with longevity, has a much simpler and less grueling test as a proxy for how your body is aging, which may or may not match your chronological age.Johnson led the exercise at Business Insider's The Long Play event in San Francisco on Tuesday. You can do it anywhere with a timer. The test: Start your timer, close your eyes, and stand on one leg. See how long you can avoid falling.According to Johnson, if you stand for zero to seven seconds, your body is 60-80 years old. Seven to 15 seconds is 40-60 years old, and 15 to 30 seconds is 20 to 40. "As you age, your brain atrophies, and your ability to maintain your balance goes away. That's why when you get older, if you fall down, it's no good," Johnson said.A small Mayo Clinic study of adults over 50 published in 2024 found that among several functional tests, one-leg balance time was most affected by age.

The Mayo Clinic researchers dubbed the one-legged test "a valid measure of frailty, independence, and fall status."Unlike Johnson's version on Tuesday night, the study didn't test people under 50, nor did it offer specifics about balance time matching biological age. The balance test isn't a new idea, and the Cleveland Clinic cautions that "it's not a complete balance evaluation on its own" and it's "far from a perfect indication of longevity."But by Johnson's standards, my biological age — especially on my dominant, more stable left leg — is right where I should be.