Free biological age test at home: what a fitness test can tell you
Two people of the same age do not age at the same pace: that is the idea behind biological age. There are several ways to estimate it, some of them expensive. Here is what each one measures, and what a simple physical test can tell you at home.
What biological age means
Biological age tries to say whether your body is aging faster or slower than your age on paper. There is no single official measure: researchers have built several, and they do not always give the same result for the same person.
Blood and DNA tests
Epigenetic clocks read chemical marks on your DNA, from a blood or saliva sample. The first was published by Steve Horvath in 2013. Kits are sold online, often for more than two hundred dollars, and the analysis is done in a lab.
Ages calculated from a blood test combine several routine results, such as glucose, albumin or creatinine. The best known, published by Morgan Levine and colleagues in 2018, combines nine of them. So you need a lab, and often a prescription.
What a physical test can estimate
Strength, balance and mobility also decline with age, at different speeds for different people. Three simple tests measure them at home, with no equipment, and compare your result with published values for your age and sex:
- getting up off the floor without hands, for mobility;
- standing on one leg, for balance;
- the 30-second chair stand, for leg strength.
Each guide has a free calculator that shows where you stand among people your age. This is better called a physical age: what your body can do, compared with others.
What a physical test does not tell you
It is not a biological age measured in a lab. A physical test reads neither your blood nor your DNA, and it does not diagnose anything. Studies link these tests to long-term health, but these are associations. Your result also varies with tiredness, the floor or how you do the test.
Its value lies elsewhere: it is quick, you can repeat it every month, and what it measures can be trained. So you can follow your progress, which a lab test rarely allows given its price.
Body age in BodyYears
BodyYears combines the three tests and your habits into one number: your body age. Your iPhone camera counts, times and scores the tests for you, and images are never recorded or sent. The calculators in these guides are free; the app itself is a subscription. The method explains the whole calculation, and its limits.
Sources
- Horvath S. DNA methylation age of human tissues and cell types. Genome Biology, 2013.
- Levine ME et al. An epigenetic biomarker of aging for lifespan and healthspan. Aging, 2018.
- Araújo CGS, Castro CLB, Franca JFC, Araújo DSMS. Sitting-rising test: sex- and age-reference scores derived from 6141 adults. European Journal of Preventive Cardiology, 2020.
- Springer BA et al. Normative values for the unipedal stance test with eyes open and closed. Journal of Geriatric Physical Therapy, 2007.
- Jones CJ, Rikli RE, Beam WC. A 30-s chair-stand test as a measure of lower body strength in community-residing older adults. Research Quarterly for Exercise and Sport, 1999.