SINGAPORE: For decades, hustle culture has been sold as the ultimate path to success, promising that those who work longer, push harder, and sacrifice more will always come out on top, but some experts are starting to suggest that this whole ‘hustle culture’ thing might not work so well once you hit your 40s.

Philip Blackett, founder of LifeAfter40.com, explains that while people are still ‘capable, ambitious, and driven’ at this stage, their energy fades faster under constant pressure, their focus slips more easily, and they burn out quicker than before.

Many of us might assume this is simply ‘losing one’s edge,’ but Blackett clarifies that it is actually the result of a combination of natural physical and psychological changes that tend to take effect around the age of 40.

So, what changes when you turn 40?

Brain

Research shows that in our 40s, the brain undergoes noticeable changes. According to Raja Hospital’s website, brain volume decreases, particularly in areas responsible for learning and memory. Levels of brain chemicals known as neurotransmitters also decline, which can affect mood and memory. 

In addition, communication between brain cells may slow, and blood flow to the brain can be reduced, both of which can affect focus and mental clarity. Together, these changes help explain why clear thinking and information processing can require more effort than they did in our 20s or 30s.

Muscle mass and mitochondria

Ever wondered why we had so much energy when we were in our 20s? Medical experts explain that this is because we had higher muscle mass and more numerous and more efficient structures that convert food into usable energy: mitochondria.

Unfortunately, once we turn 40, our muscle mass, which helps us regulate blood sugar and reduces the effort required for every task, starts to decline. Our mitochondria, although they still produce energy, also lose their efficiency.

This explains why people at this stage feel more tired and why the same level of hustle they had in their younger years is harder to sustain.

Sleep

Getting older also affects our sleep. It becomes more fragmented, with less time spent in deep, restorative rest. As a result, the body recovers more slowly, leaving us feeling tired and less refreshed in the morning. 

More mental load

Life usually gets busier in your 40s. Work responsibilities pile up, family demands grow, and many people take on leadership roles that require constant decision-making and multitasking.

All this extra mental work puts stress on the part of the brain that handles planning, decision-making, and self-control: the prefrontal cortex. 

Combine that with slower brain function, lower energy, and less restorative sleep, and it’s easy to see why you can’t push yourself the same way you did in your younger years.

Mistakes people sometimes make

When people at this age find out that hustling stops delivering the results it used to, some of them tend to push harder. 

They work longer hours, prioritise outputs over recovery, say yes to more commitments, and ignore all the warning signs their bodies give off.

However, this is a huge mistake. According to Blackett, continuing to work hard at the expense of our health can “create a dangerous feedback loop.”

Fatigue can affect people’s mood and reduce their patience, which in turn can affect how they make decisions.

Instead of responding, they react impulsively and rush their decisions, which can inevitably lead to conflict and more stress.

“The cycle isn’t obvious at first. Performance may stay high on paper, but internally, leadership begins to feel heavier,” he says.

“Confidence erodes. Creativity narrows. The work becomes less enjoyable, even as the business grows. Hustle culture doesn’t fail loudly after 40. It fails quietly by extracting more from you than it gives back.”

Shifting mindsets

Blackett says that instead of grinding nonstop, people should focus more on sustainability. That means working in a way that lasts, protecting their energy, and making sure their work can continue over the long term without burning them out.

For entrepreneurs, in particular, he recommends that they take these steps: 

Flush out the idea that exhaustion equates to commitment. According to Blackett, “being tired is not evidence of dedication.” Most of the time, it just means your body doesn’t agree with your current way of working. 

Plan your day around your energy. Do your important tasks when your brain is sharp. Think about when you are most alert and focused, and schedule tasks and breaks accordingly.

Prioritise rest. Remember, sleep, downtime, and breaks are all important. They help your brain work better and prevent burnout so you can stay productive over time.

Take time to think. Leadership and big decisions are easier when you give yourself space to pause, reflect, and make careful choices. Rushing through everything only makes it harder to be effective.

Focus on long-term performance. Instead of asking if you can do something once, ask if you can do it for years. Sustainable work is about creating habits and routines that keep you going strong over the long run.

Read also: ‘The prices are ridiculous’: Man in his 40s says he and wife can no longer afford to replace old family car despite earning ‘HDB ceiling’ salary