The Woman Who Runs on Borrowed Energy
Written by the Editorial Team.
What happens to a woman who has met every deadline, every need and every expectation on energy she did not have? The editorial team follows the research on vital exhaustion to show women 40+ what borrowed energy costs, and how recovery repays it.
She is the person others rely on. The launch ships, the team is supported, the household is organised, and the cost is paid somewhere out of sight: in sleep that no longer restores, in irritability that arrives faster than it used to, in a flatness that a weekend leaves untouched.
Researchers have a name for this pattern. They call it vital exhaustion, a state of persistent fatigue, irritability and demoralisation, and they have followed it into hospital records, stroke registers and blood tests. The findings give the phrase borrowed energy a physiological meaning.
Energy borrowed from tomorrow is repaid with interest, and the bill arrives in the body.
A pattern with a name
Vital exhaustion describes tiredness that lasts well beyond a hard week and colours how a person feels about everything else.
It combines fatigue, a short fuse and a sense of demoralisation, and it tends to build quietly in capable people who keep going.
Researchers measure it with questionnaires, which means it can be studied in large groups over many years. That is how the findings below became available.
What the heart research shows
Two large reviews pooled the evidence. One combined 11 prospective studies of more than 60,000 people and found that vital exhaustion was associated with a 36 percent increased risk of a first heart disease event.
Another pooled 13 prospective studies of more than 52,000 people and reported that vital exhaustion was associated with a 50 percent increased risk of coronary heart disease in healthy populations, and roughly double the risk of a repeat cardiac event in people who already had heart disease.
The two estimates differ because the reviews included different studies and methods, and they point in the same direction. These are associations from observational research, so they show a link without proving that exhaustion causes disease.
What the brain and blood research adds
In a cohort of more than 9,000 adults, women with the highest vital exhaustion scores had more than double the risk of ischaemic stroke, and the study found no such association in men.
A single cohort needs replication, and the result raises a question that deserves more research on women. A 2024 study in JACC: Advances followed more than 11,500 middle-aged adults without heart disease and found that higher vital exhaustion was independently associated with elevated levels of three cardiac and inflammatory biomarkers.
Severe exhaustion combined with elevated biomarkers predicted the highest risk of future cardiovascular events. Exhaustion, in other words, can leave a trace in the blood before any symptoms arrive.
The cell keeps its own accounts
Martin Picard at Columbia University, who leads the field of mitochondrial psychobiology, proposes with Murugan in a 2025 paper in Cell Metabolism that health depends on a balanced energy resistance in the body's electron flow, with both too much and too little resistance linked to ageing and disease.
It is a framework still being tested, and it offers a useful picture of the body as a system with an energy budget.
Human studies of chronic caregiving show what a long stretch of strain can look like at cell level. Mothers caring for a chronically ill child for the longest time showed shorter telomeres, lower telomerase activity and higher oxidative stress, equivalent to roughly a decade of additional cellular ageing in the most stressed women.
Borrowing has a laboratory cousin
Behavioural scientists have studied what happens when a person runs short of a resource.
In experiments published in Science in 2012, scarcity of time or money led people to focus intensely on the immediate problem and to borrow too much against their future budget.
The original authors later retested their own work, and the attention and overborrowing findings held up while the cognitive fatigue finding did not reliably replicate.
Those studies concern time and money, and they offer a human parallel for energy: when the present demands everything, the future budget gets drawn on.
The wider replication story offers a useful calibration. A 36-laboratory study of more than 3,500 participants found no reliable evidence that willpower runs out like a tank.
The exhaustion described here sits in sleep, hormones, the heart and blood markers, and it responds to recovery. The repayment plan therefore belongs to rest and regeneration, and willpower has little to add.
Why responsibility for everyone drains faster
Harriet Lerner and Murray Bowen described overfunctioning as a pattern of taking on disproportionate responsibility.
And Arlie Hochschild's The Managed Heart named emotional labour, the work of managing feelings to meet the expectations of a role.
Kate Manne has written about the expectation that women act as human givers. The research on emotional labour gives the cost a number.
A meta-analysis of 95 studies found that surface acting, the suppression of true feelings to meet a role, was substantially linked to poorer wellbeing.
And a two-year follow-up of healthcare workers found that more surface acting at the start predicted a higher risk of depressive symptoms later. Many women 40+ perform this labour daily, in rooms where they are also the steadiest person present.
Repaying the account
Recovery science is specific about what repays the account.
Sabine Sonnentag and Charlotte Fritz identified four recovery experiences: psychological detachment, relaxation, mastery and control over how you spend free time.
LA synthesis of 316 samples and more than 99,000 participants found that detachment reliably reduced exhaustion, while relaxation and mastery experiences lifted both exhaustion and performance outcomes.
A pooled analysis of 54 samples found that control over leisure time had the strongest link to vigour. Emily and Amelia Nagoski's Burnout adds that the body also needs a physical release, such as movement, breath or a good cry, to complete a stress cycle.
Small instalments, made regularly, repay more than one large holiday.
Rebuilding the reserve
Calm Power is the steady strength that grows from Core Self, and it draws on a reserve that recovery refills.
Persistent exhaustion deserves a medical conversation, and the research above gives that conversation a clear starting point: sleep, mood, heart health and the pattern of demands that built the exhaustion.
She can then lead from the steadiness that returns. Decisions come more clearly from a settled centre, relationships receive attention that is freely given, and ambition draws on capacity that regenerates.
Ready to understand your current recovery needs more precisely?
What's next
FAQ
What is vital exhaustion?
Vital exhaustion is a state of persistent fatigue, irritability and demoralisation that researchers measure with questionnaires. It lasts beyond ordinary tiredness and tends to build over months or years.
Practical step: notice whether your tiredness lifts after a proper break, and mention a pattern that does not lift to your GP.
Is vital exhaustion the same as burnout?
Both describe persistent depletion, and they come from different research traditions with different measures. The studies in this article used vital exhaustion measures.
Practical step: describe your symptoms in specific terms, such as sleep, mood and energy by time of day, to help a clinician place them.
Does exhaustion cause heart disease?
The studies show associations from observational research, and the estimates vary between reviews. Exhaustion may be both a warning sign and a contributor, and the direction of cause is still being studied.
Practical step: keep up with routine blood pressure and cholesterol checks, and mention persistent exhaustion at them.
Why do the findings on stroke focus on women?
One cohort of more than 9,000 adults found a strong association in women and none in men. The result needs replication, and it highlights how much research on women's exhaustion is still to be done.
Practical step: treat the finding as a reason to take your own exhaustion seriously, and share it with your GP.
When should I seek medical advice?
Seek advice when exhaustion lasts more than a few weeks or comes with low mood, breathlessness, palpitations or unexplained weight change. Chest pain, sudden weakness, facial drooping or difficulty speaking need urgent medical attention. This article offers education and does not replace medical advice.
Practical step: book an appointment this week and bring a short note of what has changed.
Curious to explore more?
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