Your Nervous System is Working Overtime — And it’s Draining Your Energy Bank
Have you ever felt completely drained after a stressful day—without having done anything physically strenuous?
That’s your nervous system talking.
When our brain and body sense a threat — whether it’s a real danger, an emotionally charged conversation, a sudden loud noise, or just a long to-do list — our nervous system goes from calm, cool, and collected to “activation mode.” This could look like anxiety, panic, overwhelm, dissociation, disconnection, or even our basic survival responses of fight, flight, freeze, or fawn. This activation isn’t free; it costs us by quickly depleting our energy banks.
Why Activation Costs So Much Energy
Think of your nervous system like a computer. For normal every-day work, it hums along smoothly, using just enough energy to keep things running, usually having some battery life left at the end of the day. But when a big demand hits, like high-def gaming or opening 137 tabs at once, the battery drains quickly — promoting a run for the charging cable.
When your nervous system is suddenly, or chronically, activated, a few things happen:
Your brain ramps up activity in areas that process danger, make quick decisions, and scan for threats. (Looking for tigers!)
Your body releases stress hormones (like adrenaline and cortisol) that increase heart rate, breathing, and muscle tension — readying you for action. (Ready to run if there is a tiger.)
Digestion, immune function, and long-term repair get deprioritized so more resources can go to immediate survival. (Who cares about long term goals when there’s immediate danger!?)
All of that shifting and readying takes a lot of fuel — glucose for your brain, oxygen for your muscles, and micronutrients for the chemical messengers in your body. Your nervous system is only about 2% of your body weight, but it can use up to 20% of your total energy supply, and that percentage can spike even more when you’re stressed.
Why You Feel “Spent” After Stress
When you’ve been in an activated state for minutes, hours, or days, your body is running in high gear. That means:
You burn through energy reserves quickly.
Your sleep quality may be disrupted (which makes recovery harder).
Even small stressors feel heavier, because your nervous system hasn’t had time to reset into a low-power mode.
This is why you might feel like you’ve “hit a wall” after emotional conversations (like therapy sessions!), work deadlines, parenting challenges, or social anxiety - even if you didn’t move much physically.
Supporting Your Nervous System (and Your Energy)
You can’t completely avoid nervous system activation — it’s a survival tool, and we need it — it keeps us safe! But you can help your nervous system shift back into a calmer, more energy-efficient state more quickly with some mind and body awareness.
Some ways to do this:
Breathe slow and deep - exhale longer than you inhale to signal safety.
Ground your senses - notice 5 things you can see, 4 you can touch, 3 you can hear, 2 you can smell, 1 you can taste (strong tastes work very well – like something very sour).
Move gently - a short walk or stretching can help release built-up stress hormones.
Rest and nourish - give your body protein, complex carbs, and hydration to replenish energy stores. Rest as much as you need to – rest is GOOD.
Close “background apps” - Write down your to-do list, journal, or use a note-keeping system to reduce the amount your nervous system has to hold inside all for the time.
Support short and long-term emotional wellness and nervous system regulation by attending therapy, support groups, and regulation activities that help close the “pop-ups” and remove the “viruses” from your system while providing stabilization and support.
The Takeaway
Your nervous system is an incredible, hardworking part of you. Like any high-performance system, it can overheat if it’s running on max power for too long or suddenly has a large demand placed on it. Understanding that your exhaustion after stress isn’t “all in your head” can help you give yourself permission to rest and recover.
Your energy levels aren’t just supporting the running and working — they support the quiet, constant work your nervous system is doing behind the scenes to process, heal, grow, learn, and adapt. And that work deserves plenty of care and recharging.