The Science of Stress: How to Manage Stress and Build Psychological Resilience | Huberman in Conversation with Epel

Stanford neuroscientist Andrew Huberman sits down with stress science expert Dr. Elissa Epel to systematically unpack one of the most widely misunderstood concepts in modern life: stress. Stress isn't inherently destructive. What matters isn't the stressor you encounter, but how you respond to it. This article distills the most actionable scientific insights from their conversation.

Stress Is Not One Thing: Good Stress vs. Bad Stress

As a stress scientist, Epel begins by emphasizing that "stress" must be broken down. It comes in good and bad forms, and in acute and chronic varieties. Technically speaking, stress is "that feeling of being overwhelmed when demands seem to exceed our resources."

But life itself is a continuous process of meeting challenges. We can never eliminate stressors — if anything, they're increasing. What truly determines our health is the stress response, not the stressor itself.

"When something happens, we mount a stress response, and then we recover. That's beautiful — there's no harm. We need it. It's the survival response that kept humans alive." Epel notes that the modern problem is that "we keep the stress alive in our minds, sustaining it through our thoughts."

She reminds us that thoughts are the most common form of stress. Many people spend their days in a "red-mind" threat mode without even realizing it. A key clue lives in the body: we may not notice we're tense, but our hands are clenched.

Three Strategies for Dealing with Overthinking

For the kind of "rumination" — repeatedly chewing on stressors and being unable to let go — Epel organizes coping strategies into three categories:

Top-Down: Beliefs and Mindset

The first is awareness and self-talk — releasing stress and viewing it more positively by changing beliefs and mindset. This requires first understanding how our own minds operate, otherwise we passively "believe our thoughts are real and that constant rumination and problem-solving are helpful."

Bottom-Up: The Body Changes the Mind

The second doesn't use the mind to change the body, but rather uses the body to change the mind. Through movement and exercise, we "metabolize and burn off" stress to find relief. This shifts activity in the amygdala, pulling us into a more somatosensory-cortex-based state of experience. It's also the strategy Huberman himself uses most.

Changing the Scene: Safety Signals

The third is simply "changing your environment" — leaving the office or the stress triggers of the city and placing yourself somewhere that brings calm. Even a corner of your home, arranged with what Epel calls "safety signals": a comforting pet, photos, scents, music.

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Rumination in psychology refers specifically to the repetitive, passive mental replay of negative events or emotions — not active, solution-oriented thinking. The key difference from simply "thinking something through" is that rumination produces no new insights or action plans; it just loops the same painful mental content through consciousness. Extensive research identifies rumination as one of the strongest maintenance factors for depression, and it's closely linked to anxiety disorders and PTSD. Neurologically, rumination is associated with overactivation of the default mode network — the circuit that runs automatically when the brain has "no task" — which is why people most often fall into rumination during idle moments or before sleep. Understanding this mechanism helps explain why "bottom-up" physical strategies like exercise can interrupt it: physical activity forcibly activates the motor and sensory cortices, competitively suppressing the default mode network's overactivity.

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Threat Response vs. Challenge Response: Two Physiological Pathways

One of the most illuminating parts of the conversation is Epel's distinction between two psychological stress responses.

Two people facing the exact same stressor can respond entirely differently. Someone who feels their survival or social standing is threatened will experience a "threat response": elevated cortisol, high vasoconstriction, and blood pressure that rises as vessels constrict. Someone who sees the same stressor as "I can do this — this is an opportunity" experiences a "challenge response": blood pressure also rises, but in a healthier way — higher cardiac output, better brain oxygenation, and improved problem-solving ability.

Lab data shows that people exhibiting a challenge response have lower inflammation after the stressor ends, and their telomeres tend to be longer — meaning slower biological aging. Threat responders recover more slowly; that gut-churning, heart-pounding, overamplified reaction is biologically distinct.

The good news is that the challenge response can be trained. Research by Wendy Mendez and others on "reappraisal" shows that when people are trained to view stress positively — "this stress response is empowering, my body is doing what it's supposed to do" — they perform better under pressure, feel more positive emotion, and recover faster.

Epel uses the analogy of "be the lion, not the gazelle": both are in a high-blood-pressure, high-stress state, but the gazelle is in a full threat response because it might die, while the lion is in a challenge response because it's excitedly chasing prey. "We can remind ourselves: be the lion."

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Telomeres are protective DNA sequences at the ends of chromosomes, functioning like the plastic caps on shoelaces — preventing chromosomes from fraying during replication. Each time a cell divides, telomeres shorten slightly; when they reach a critical length, the cell stops dividing or undergoes apoptosis. Telomere length is therefore considered a marker of cellular biological age, closely tied to overall lifespan and the risk of various chronic diseases. Epel herself gained wide recognition through her collaborative research with Elizabeth Blackburn on how chronic stress accelerates telomere shortening — Blackburn went on to win the 2009 Nobel Prize in Physiology or Medicine for her work on telomerase. The differential impact of the two stress response pathways on telomeres demonstrates that psychological coping style can leave measurable biological imprints at the cellular level.

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Moderate Stress Makes You Stronger: Building Stress Resilience

Huberman draws a parallel to exercise: during intense workouts, blood pressure, heart rate, and cortisol all spike, yet the long-term adaptation is lower blood pressure and improved cardiovascular function.

Epel confirms that brief, repeated physiological stress — like high-intensity interval training — not only improves aerobic capacity but also builds "stress fitness": rumination, depression, and anxiety all decrease, essentially recalibrating the nervous system.

The same applies to psychological stressors: "When we habituate to moderate stressors, we become more robust and stress resilience builds" — meaning we're less likely to feel threatened by them. The critical condition is that the stress must be manageable, and we must not continue ruminating on it for the next 24 to 48 hours.

Facing Unchangeable Chronic Stress: Drop the Rope

For people under prolonged uncontrollable chronic stress — like caregivers — Epel's research has yielded a surprising finding.

She studies how chronic stress accelerates cellular aging, yet found enormous variation between individuals: "Among caregivers, some looked biologically just as young as our control group — or even younger." This shows that coping strategies are critical.

In one study of mothers caring for children with autism, the caregiving mothers showed significantly reduced mitochondrial activity — they couldn't generate as much energy, which directly explains the exhaustion that chronic stress produces. But the caregivers whose mitochondrial enzyme function remained intact reported more positive emotions — especially in the evenings.

Epel underscores the importance of "nighttime positive emotion": at the end of a difficult day, can you access any sense of satisfaction, ease, confidence, or joy? Research shows that people with lower negative emotion or higher positive emotion have significantly lower risk of depression, heart disease, and early death a decade later. The study also found that daily emotional state was highly correlated with same-day mitochondrial levels — suggesting that "our mitochondria are sensitive to thoughts and feelings, very likely on a day-by-day basis."

For stressors that cannot be changed, Epel proposes "radical acceptance." She uses a vivid metaphor:

"Imagine you're pulling on a rope tied to a brick wall. You pull and pull, every day, but the wall won't move. The only result is that your hands get torn up. So — why not just drop the rope?"

"Drop the rope" — that's what she tells herself when she's trying to solve an unsolvable problem. The wall is still there; it will never move. But your hands are free, and your resources can be redirected toward the things you actually can control.

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Mitochondria are organelles within cells responsible for converting nutrients into energy (ATP), often called the "powerhouse of the cell." Chronic stress damages mitochondrial function through sustained cortisol secretion, oxidative stress, and other mechanisms — reducing cellular energy production in a way that directly corresponds to physical fatigue and cognitive sluggishness. Recent research has also revealed that mitochondria aren't just passive energy factories: they participate in regulating neurotransmitter synthesis, immune signaling, and even apoptosis, meaning their functional state has a bidirectional relationship with emotional regulation. Epel's finding that mitochondrial enzyme activity correlates with daily emotional states suggests that our psychological experiences may influence cellular energy metabolism in near real-time — not merely through long-term accumulation.

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Embracing Uncertainty and the Power of Narrative

Epel points out that humans have an intense desire to control the future, because predictability allows us to relax and stop staying on guard. But "tolerance for uncertainty" is a rare and valuable resilience factor — people who can tolerate uncertainty experience less anxiety and depression, and recover more quickly from stressful events.

She even offers a physical practice: rather than maintaining that vigilant, forward-leaning posture of trying to predict the next moment, lean back, take a few slow breaths, and enter an "acceptance mode" — approaching what's about to happen with curiosity. This is the opposite of the typical daytime "forward-charging mode."

Huberman extracts a framework from this: stress management requires both the active mode of "leaning in, charging through challenges" and the receptive mode of "leaning back, flowing with what comes." Epel uses surfing as a metaphor: "We're in the ocean — there are small waves and big waves, and the next one will always hit us. The key is to ride them skillfully." She summarizes: "Exert force when you can; let go when you hit a brick wall."

On the value of writing, Epel is unequivocal: constructing a coherent narrative is essential for understanding our experiences, finding meaning, and working through difficulty. "In stress research, what matters isn't what happened — it's how we interpret it and how we respond." A narrative organized around "purpose" is precisely what distinguishes humans from the monkeys and mice in laboratory experiments — we can project into the future and ask what our lives mean.