Scientists use epigenetic clocks to determine age via changes in DNA. These clocks mainly look at substances in the blood to make an estimate of how fast someone is ageing biologically. Among other things, this involves looking at methylation, a chemical modification of the DNA that changes with age.
New research shows that these epigenetic clocks do not react strongly to a person's physical condition. This is striking, because better fitness is usually associated with a longer life expectancy. It means that the clock primarily measures other processes in the body that are less directly influenced by exercise or sports.
This insight can help in refining techniques to track ageing and better understand which factors most influence health and lifespan. Although physical fitness remains essential for a healthy life, it turns out that its effect cannot be easily captured in these epigenetic models.
For those wanting to invest in healthy ageing, it is important to know that being fit remains valuable, even though some clocks do not measure this directly. Exercise contributes to wellbeing and longevity in many ways, even independently of genetic changes.
Source: Reason
