Not All Stress is Bad: Here’s the Science Behind Good Stress

Stress has a reputation problem. Most people treat it as something to eliminate entirely, a sign that something has gone wrong. But decades of research in performance psychology tell a different story. The right kind of stress, applied at the right level, is one of the most powerful drivers of human growth available to us.

According to Dr. Sharon Horesh Bergquist (2025), a leading researcher on the science of “good stress,” the optimal kind of psychological stress is characterized by choice, control, and predictability. It brings stimulation and excitement, adding a degree of uncertainty that stretches and challenges us, but not to the point of overwhelm. Importantly, this type of stress also aligns with our sense of purpose and service to others, which can deepen our sense of fulfillment. “Good stress” is experienced in intermittent, low-moderate doses, it gently stretches us beyond our comfort zone, enough to promote growth, but never so much that it becomes unmanageable.

Understanding this distinction is particularly valuable for educators and youth-serving professionals. When you grasp how stress actually works, you can use that knowledge to foster resilience in the young people you support, and in yourself.

The stress spectrum: from rustout to burnout

Psychologist Hans Selye, who coined the term eustress in 1975, was the first to draw a clear line between stress that harms us and stress that helps us thrive. His insight was straightforward but profound: too little stress is just as problematic as too much.

Think of it as a spectrum with three zones:

• Understress (rustout): Too little stimulation leads to boredom, disengagement, and underperformance. Skills atrophy. Motivation fades.
• Eustress (optimal): The sweet spot. You feel energized and focused, performing at your best and growing in the process.
• Distress (burnout): Chronic overload leads to overwhelm, fatigue, and declining performance, with real consequences for long-term health.

The goal isn’t to avoid stress. It’s to find the optimal zone, what researchers call the eustress zone, where challenge activates growth rather than damage.

The biology of beneficial stress: hormesis

The mechanism behind eustress is called hormesis, a biological principle that has been preserved across millions of years of evolution. The core idea is simple: intermittent, low-dose stressors stimulate a beneficial biological response that makes us stronger and more resilient.

You already know this principle in action, even if you haven’t named it:

• Exercise is controlled physical stress. At the cellular level, it triggers repair mechanisms, builds mitochondrial density, and produces factors that strengthen the brain.
• Vaccines introduce a small “dose” of threat, training the immune system to mount a powerful future defense.
• Cognitive challenge, learning, problem-solving, navigating difficulty, creates productive neural stress that strengthens synaptic connections and builds cognitive reserve.

As researcher Elissa Epel (2020) explains, hormesis is “the set of evolutionary well-preserved mechanisms of biological plasticity to survive and thrive when exposed to harsh circumstances.” We are not designed to be protected from all stress. We are designed to be challenged by it, intermittently, and within our capacity to recover.

When stress turns toxic

Stress doesn’t become toxic simply because it’s intense. Research is clear on this point: stressors become harmful when they are chronic and paired with a perceived lack of resources.

An acute stressor, a hard workout, a difficult exam, a challenging conversation, is manageable and even beneficial when it resolves. A demanding job can actually be health-promoting if you feel capable and supported. It’s the combination of ongoing stress and the feeling that you don’t have enough to cope that tips the balance toward toxicity.

Over time, this combination leads to allostatic load, the cumulative wear and tear on the body from chronic stress activation. The same cortisol and adrenaline responses that sharpen focus in the short term begin to cause immune dysregulation, cardiovascular strain, and accelerated cellular aging when they never fully switch off.

The power of appraisal

Here is one of the most empowering findings in stress science: how we interpret a stressor shapes our biological response to it.

When we appraise a demanding situation as a challenge, difficult, but within our capacity, we enter a fundamentally different physiological state than when we appraise the same situation as a threat. Challenge appraisals produce greater cardiovascular efficiency, enhanced cognitive function, and hormetic activation. Threat appraisals, when chronic, produce allostatic load.

This is where coaching and education become powerful interventions. When you help a young person identify their existing resources, build new skills, and reframe a difficult situation as manageable, you are not just offering encouragement. You are directly influencing their biology.

Building stress resilience in youth

Resilience isn’t a fixed trait, it’s a dynamic capacity that expands with resources. Research identifies several areas where educators and coaches can make a meaningful difference:

• Skill development: Competence builds confidence. When young people know how to do something, it feels like a challenge; when they don’t, it feels like a threat.
• Social connection: Supportive relationships produce hormones that directly reduce stress and strengthen immune function.
• Physical foundations: Sleep, movement, and nutrition are the biological scaffolding for stress resilience.
• Perceived control: Helping youth identify what is genuinely within their power is a direct intervention on the appraisal process.

The science is clear: stress, used wisely, is a growth tool. Your role is to help young people find, and stay in, their optimal zone.