Priya is a classic go-getter at the age of 68. Even in retirement, she keeps herself constantly occupied with housework, errands, dancing classes, volunteering and even an online course. Her children joke that she can’t “keep still”. Then there’s her good friend, Jason. At 70, he prefers a slower rhythm: long naps, reading, gardening and occasional coffee dates. He passes his days retreating from the world, enjoying a more measured pace – a well-earned reward after decades of work. Which of these friends is ageing
better, at a biological level? The answer may be surprising – neither. Life expectancy in Singapore has risen dramatically from about 65 years in the 1960s to over 83 years today, and continues to climb. Against this backdrop, much has been said about the need to keep ourselves occupied to guard against the natural physical and cognitive decline that comes with age. After all, doesn’t keeping busy keep you young? Not necessarily. Age is not just a number We often speak of age as a
single number. But there are two distinct concepts: Chronological age is the number of years lived, and biological age reflects how well our cells are functioning. While chronological ageing follows a strict formula – every passing year adds an increment – biological ageing is more dynamic. Two people of the same chronological age can show surprisingly different biological ageing trajectories. A recent study from the Yale School of Public Health, tracking more than 11,000 adults over 65 in the United States, found that nearly half
showed marked improvements in physical or cognitive function after a decade – challenging the common assumption that ageing inevitably means decline. So, what explains whether an individual will improve or decline, or maintain his level of function over time? Genetics plays a part. But so do our daily routines. Imagine a bucket that’s collecting water throughout your life. Each stressor, whether illness, a looming deadline or financial pressure, adds a trickle. The water level represents your “allostatic load”. It’s the cumulative wear and tear on
your body from stress, both physical and psychological. When it overfills, that’s known as allostatic overload. And if it’s not “emptied”, the body remains in a prolonged state of strain, without enough room for our cells to recover. Cells that can’t repair themselves accumulate damage, accelerating the ageing process. An empty bucket is just as harmful. This is allostatic underload. Without enough physical, cognitive or social stimulation, our cells weaken from underuse. Priya is engaged, connected and active – all of which support healthy ageing.
But without enough rest, she is at risk of overload. Jason’s prioritising of rest and recovery is also beneficial for healthy ageing. But without enough stimulation, his body will gradually become weaker, also accelerating ageing. Rhythm and meaningful challenge The key to healthy ageing lies in setting the right “rhythm”. It’s about building sustained habits over time – an extended period of faster-paced, challenging activity, followed by a period of slower, intentional rest. By design, buckets are meant to be filled, then emptied. Stay too
full for too long, and they strain under pressure. Remain empty for too long, and the sides can become brittle and crack. Our bodies are the same. When our cells experience a healthy amount of challenge followed by sufficient recovery time, they grow stronger. Meaningful challenge paired with intentional rest helps to build our physiological reserve. This refers to the body’s “stores” – a little extra in the tank – that help us bounce back more quickly from illness, injury and life’s inevitable bumps. This
surplus gives our cells the room to repair and replenish, rather than accumulate damage. Meaningful challenge could look different for everyone and does not require a relentless schedule. Some might find purpose and stimulation in work, volunteering, rock climbing or learning a new skill. Others may gain the same benefits from solving puzzles or gardening. Intentional rest, on the other hand, simply means carving out pockets of time free from constant demands and stimulation, whether you prefer leisurely walks, reading or spending time with family
and friends. Rest is not about doing nothing entirely, but about allowing the body and mind enough space to recover. So, how long should these periods of rest and meaningful challenge be? In the context of doing voluntary work, research from the Centre for Ageing Research and Education (CARE) at Duke-NUS Medical School highlights how volunteering can boost quality of life for older adults, particularly when it offers a sense of purpose and structure without becoming an obligation. A global review suggests that two or
three hours of volunteering a week seems to be the “sweet spot” for building physiological reserve, while more than 10 hours can negate the physiological benefits. While Priya and Jason have contrasting rhythms, both can benefit from making small changes to their routines to slow down biological ageing. For Priya, intentionally stepping back from some activities and building in more rest periods in her day would help lower her allostatic load. Meanwhile, Jason can add more meaningful stimulation, like joining a weekly interest group or
volunteering in his neighbourhood, to prevent his cells from weakening. Of course, changing routines may not be possible for everyone. Work, caregiving and financial responsibilities sometimes cannot be paused. Yet, the science is encouraging. A single month or year, or season in life, will not define your overall trajectory. It’s the sustained rhythm over time that counts, and even small shifts can have a surprisingly big impact. For example, one UK-based study found that an intentional break – in the form of a 10-minute walk
– in the middle of the day reduces the risk of premature death by about 15 per cent. The dose is small, but the cumulative effect over years adds up to meaningful biological benefits. Finally, ageing is shaped not only by what we do. Our mindset and how we think about growing older are also critical, as the Yale study shows. Older adults with more positive beliefs about ageing were more likely to show gains in cognition and mobility over time, even when factors such
as education, chronic disease and depression were considered. CARE’s own research supports this. When we tracked 3,495 Singaporeans aged 60 and older for up to six years, we found that personal mastery – having a strong sense of control over one’s life – emerged as a key factor in longevity. Ultimately, older Singaporeans with high personal mastery lived longer and spent more of their remaining years free from health difficulties, compared with those with low personal mastery. Older adults who see ageing as a time
for growth, contribution and enjoyment are more likely to remain socially, physically and cognitively active, balanced by intentional rest. But those who internalise negative stereotypes about ageing – believing that decline is inevitable – can risk withdrawing from life. Rethinking ageing in terms of ‘rhythm’ In Singapore, a nation built on hard work, productivity and the trademark “kiasu” drive, the ideas of keeping busy and “active ageing” are particularly resonant. But remaining active is only part of the picture. When did you last feel genuinely
rested or genuinely challenged? If you can’t remember, your rhythm needs a tweak. The calendar shows how many years have passed, but it’s your rhythm and mindset that shape the years to come.
healthy ageing, rhythm, biological age, allostatic load, allostatic overload, allostatic underload, physiological reserve, volunteering, personal mastery, Singapore