When we neglect our health to serve the company, we are not sacrificing for its success. We are spending down the exact resource that success runs on. This piece is about why health is not a private matter parked outside of work, but the physiological foundation our judgement, resilience and stamina are built on.
Earlier pieces in this series looked at how breath helps us stay calm, think clearly, and lead others well under pressure. All three depend on something more basic still: the underlying health of the body producing them. Deplete that, and everything built on top of it weakens too — usually before we notice.
Does our body set the ceiling on our leadership?
We tend to think of leadership as something that happens in the mind: judgement, vision, decisions, the ability to read a room. But the mind runs on a body, and the quality of what the mind produces is shaped, moment to moment, by the state that body is in.
Health is not a competing priority that steals time from leadership. It is the foundation leadership stands on. That foundation shows up in four ways that matter for every leader.
- Our decisions are only as good as the data we base them on. Every decision rests on our read of the situation, and the brain builds that read from signals coming up from the body. When the body is off balance — under-recovered, inflamed, depleted — perception gets skewed, and we end up deciding on corrupted data.
- Emotional steadiness depends on a resilient nervous system. Being the anchor for a team in a crisis is not a question of willpower. It depends on a nervous system that can regulate itself, and that capacity erodes when the body is depleted.
- Clear thinking sits on top of how rested and regulated we are. Under stress the body pulls resources away from the prefrontal cortex toward faster, reactive circuits. Poor sleep, skipped meals, too much caffeine and no real recovery all push in the same direction.
- Sustained performance is built on recovery, not just effort. Like elite athletes, we perform through rhythmic cycles of exertion and recovery on a strong physical base — not through constant exertion. Ignore the body, and we eventually run a deficit no amount of discipline can cover.
How does unmanaged stress erode health and leadership at once?
The conditions we operate in as leaders keep the stress response switched on by default: high stakes, incomplete information, constant decisions, little recovery.
The problem is not activation itself. A moderate dose is exactly what gives us access to high performance. The trouble comes in three distinct forms:
- In the short term, the problem is too much activation. When the stress response tips into the "too much" range, we lose access to the prefrontal cortex and drop into reactive fight, flight or freeze.
- In the long term, the problem is the lack of quality recovery. The body is built to spike and then return to baseline. What wears it down is spiking without ever fully coming back — the accumulated cost researchers call allostatic load, which over time is linked to worse health, including higher cardiovascular risk.
- Eventually, the ability to recover itself degrades. This is the most dangerous stage, because the body's own reset is what is failing. The early signs are worth knowing: not being able to wind down after a hard day, unrefreshing sleep, a racing mind at night, irritability, and relying on stimulants to start and something to switch off.
A few of the ways this plays out lead straight back to leadership.
Stress changes how we breathe, and worse breathing feeds the stress
Under pressure, breathing becomes faster, shallower and higher in the chest. Instead of calming the body back down, that kind of breathing keeps the alarm switched on.
Chronic overbreathing lowers carbon dioxide in the blood. Through the Bohr effect, this can reduce how much oxygen actually reaches the brain — even with high oxygen saturation in the blood, uptake into brain tissue drops. The result is a loop that is surprisingly common: stress drives the breathing pattern, and the breathing pattern drives more stress.
Stress affects our sleep, and poor sleep steals our regulation
A nervous system stuck in overdrive struggles to downshift into the rest the body needs to repair. Sleep is also the brain's most effective way to clear the metabolic waste that accumulates through the day, so lost sleep means that clean-up does not fully happen.
Because the prefrontal cortex is especially sensitive to lost sleep, the damage shows up exactly where leaders can least afford it: working memory, emotional control and decision quality. It becomes a trap — stress wrecks our sleep, and poor sleep wrecks the very regulation that would help us handle stress.
This is also the change people notice first when they start working with breath. The reports are specific and, increasingly, measured.
"Last year, I was not able to sleep at all. I slept between three and four hours, and that was not a good sleep. I was always tired during the exam. This time, I have every day almost seven hours of sleep — because I was able to get into this peace where I was able to sleep again." — Katlehyn Jotty, Lawyer-to-be
"The most interesting thing I realised was — I use an Oura ring, and I realised that my sleep score increased, and my HRV, my heart rate variability, increased too. That was quite interesting because my breathwork sessions were really short but continuously a couple of times during the day." — Nathalie Mielke, Founder; ex-Partner, EY
Stress drives chronic inflammation, and inflammation can cloud the mind
When the stress response stays on, the body drifts into a low-grade inflammatory state. Those inflammatory signals reach the brain and can produce fatigue, low mood, withdrawal, and the dullness many of us call brain fog. The fog is not a character flaw. It is often a physiological signal worth listening to.
Stress unsettles the gut, and the gut talks back to the mind
Chronic stress also disrupts the gut, and a growing body of research points to a two-way line between gut and brain that can influence mood, anxiety and clear thinking. The gut is the body's largest site of serotonin production, which is part of why an unsettled gut and an unsettled mind so often travel together.
What do people notice when they train recovery?
When breath becomes a regular practice rather than an occasional rescue, the change tends to show up first in the body's recovery markers — and several leaders now track it directly.
"I learned that breath can be a very effective and simple tool to reduce stress, both the baseline stress and in the moment. I am wearing a Whoop — it also measures stress levels. From the data I see that the stress levels are lower." — Tim Ermak, Founder & Senior AI Product Manager
The common thread across these accounts is not a feeling of vague wellness. It is deeper, less interrupted sleep, higher heart rate variability, and lower measured stress load — the physiological base that steady judgement and stamina are built on.
What happens to a team when a leader is depleted?
None of this stays contained in one body. It surfaces as what the team actually experiences: a leader who is more irritable than the moment warrants, who misreads the room, who reaches for the familiar answer instead of the better one, who has stopped being curious.
And it is measurable. In one large study of physician leaders, those rated independently on their effectiveness scored noticeably lower as their burnout rose — a leader's own burnout explained close to a tenth of how effective they were judged to be by the people they led (Shanafelt et al., JAMA Network Open, 2020).
Our health is not just a private matter. It becomes something our decisions, our relationships and our team all quietly run on.
So what do we actually do about it?
If our health sets the ceiling on our leadership, the real question is what to do — especially when stress is, to some degree, part of the job. That is the subject of the next piece, which looks at how breath gives us a direct, practical handle on protecting the health our leadership depends on.
Sources & further reading
Shanafelt, T. D., Makowski, M. S., Wang, H., et al. Association of burnout, professional fulfillment, and self-care practices of physician leaders with their independently rated leadership effectiveness. JAMA Network Open, 3(6), e207961 (2020). https://doi.org/10.1001/jamanetworkopen.2020.7961
Loehr, J. & Schwartz, T. The making of a corporate athlete. Harvard Business Review, January 2001. https://hbr.org/2001/01/the-making-of-a-corporate-athlete
Goldstein-Piekarski, A. N., et al. / Walker, M. P. The sleep-deprived human brain. Nature Reviews Neuroscience, 18, 404–418 (2017). https://doi.org/10.1038/nrn.2017.55
McEwen, B. S. Protective and damaging effects of stress mediators: central role of the brain (allostatic load). Dialogues in Clinical Neuroscience, 8(4), 367–381 (2006). https://doi.org/10.31887/DCNS.2006.8.4/bmcewen
Cryan, J. F., et al. Stress and the gut-brain axis. Neurobiology of Stress, 7, 124–136 (2017). https://doi.org/10.1016/j.ynstr.2017.03.001
Laborde, S., Allen, M. S., Borges, U., et al. Effects of voluntary slow breathing on heart rate and heart rate variability: A systematic review and a meta-analysis. Neuroscience & Biobehavioral Reviews, 138 (2022). https://doi.org/10.1016/j.neubiorev.2022.104711
Frequently Asked Questions
Why does physical health matter for leadership?
Because the mind runs on a body. Judgement, emotional steadiness, clear thinking and sustained performance are all shaped moment to moment by the state of the body producing them. When health is depleted — through poor sleep, chronic stress, or no recovery — the capacities leadership depends on degrade too.
How does chronic stress harm both health and leadership?
The problem is rarely activation itself but the lack of recovery. Repeated stress spikes without a full return to baseline accumulate as allostatic load, which over time is linked to worse health, including higher cardiovascular risk. Eventually the body’s ability to recover degrades, and judgement and steadiness go with it.
How does stress affect sleep and thinking?
A nervous system stuck in overdrive struggles to downshift into restorative sleep, and sleep is when the brain clears metabolic waste and resets emotional regulation. Because the prefrontal cortex is especially sensitive to lost sleep, the damage shows up in working memory, emotional control and decision quality.
Can a leader’s poor health affect the whole team?
Yes. A depleted leader tends to be more irritable, to misread the room, and to reach for familiar rather than better answers. In one large study, leaders’ independently rated effectiveness fell measurably as their burnout rose.
Can breathing actually change these health markers?
Slow, regular breathing supports deeper sleep, higher heart rate variability and lower measured stress load — changes several leaders now track directly on wearables. It is one of the most direct, practical levers we have on the physiological base that steady judgement and stamina rest on.