5 ways to improve your sleep (at no charge)

Your nervous system is like a DJ and sleep controls the playlist.

And right now, after 40, for many of us? The tracks are a little… intense.

Over the past few weeks, as part of our Eir Presents: The Sleep Upgrade, for Sleep Awareness Month, we’ve covered the foundations – how much sleep you need, why it matters, why women’s sleep is biologically different, and simple ways to improve it. 

This week, we’re going deeper.

Because it’s not just your hormones disrupting the bedroom.

It’s your nervous system.

The Low-Grade “Fight or Flight” We Don’t Talk About

After 40, many women live in subtle but persistent sympathetic activation – the “fight or flight” branch of the nervous system.

Emails. Family logistics. The invisible mental load. Caring for everyone else.
Even if you look calm on the outside, your nervous system may still be scrolling.

Chronic stress keeps the hypothalamic–pituitary–adrenal (HPA) axis switched on, increasing cortisol output [1]. And here’s where it gets cyclical:

Poor sleep increases next-day cortisol levels. Elevated cortisol makes it harder to fall asleep the following night. And that loop? It compounds. [2,3]

Women are also disproportionately affected by anxiety and insomnia, partly due to hormonal influences on stress circuitry and amygdala reactivity [4].

So if your system feels more sensitive than it used to – you’re not imagining it.

This is biology intersecting with responsibility.

The Good News: Sleep Is a Nervous System Regulator

Here’s what’s powerful. Sleep isn’t just passive rest. It’s active neurological recalibration.

During healthy sleep:

• Cortisol declines at night and rises naturally in the morning in a predictable rhythm [5]
• Heart rate variability (HRV), a marker of parasympathetic tone, improves [6]
• Emotional reactivity decreases
• The amygdala (your brain’s threat detector) becomes less reactive after adequate sleep [7]

In one landmark study, sleep deprivation increased amygdala reactivity by up to 60% meaning the brain becomes significantly more emotionally reactive when under-slept [7].

In other words?

Good sleep literally makes you calmer.

Not metaphorically.
Neurologically.

The Trick Isn’t Forcing Sleep. It’s Signalling Safety.

Here’s what we continue to learn as we get older, and wiser – you cannot bully your nervous system into rest. You can, however, cue safety. Always. 

Before bed, try:

• 4–6 breathing (inhale 4, exhale 6) – longer exhales stimulate vagal tone
• Legs up the wall for 5 minutes – gentle inversion supports parasympathetic activation
• A warm shower followed by a cool bedroom – passive body heating followed by cooling helps initiate sleep onset [8]
• A “brain dump” journal – expressive writing reduces cognitive arousal at bedtime [9]

And one of the most underrated tools?

Morning light.

Getting natural sunlight within 30 minutes of waking strengthens circadian rhythm alignment and improves melatonin timing that night [10].

It’s simple.
It’s free.
It’s powerful.

The Feedback Loop That Works in Your Favour

The calmer your system feels, the deeper your sleep becomes.
The deeper your sleep becomes, the calmer your system feels.

That’s not a vibe.

That’s neuroscience.

After 40, this isn’t about hustling harder or pushing through fatigue. What we’re doing here is recalibrating the system that runs everything.

And when your nervous system feels safe?

Your sleep stops fighting you.

We’re here to help you find calm, 

Love Lisa & Kate 

References

[1] McEwen BS. Physiology and neurobiology of stress and adaptation. Physiol Rev. 2007.
[2] Leproult R, Van Cauter E. Effect of sleep loss on HPA axis activity. J Clin Endocrinol Metab. 2010.
[3] Vgontzas AN, et al. Insomnia and activation of the HPA axis. J Clin Endocrinol Metab. 2001.
[4] Goldstein JM, et al. Sex differences in stress response circuitry. Biol Psychiatry. 2010.
[5] Buckley TM, Schatzberg AF. On the interactions of the HPA axis and sleep. Sleep Med Rev. 2005.
[6] Tobaldini E, et al. Sleep, autonomic regulation and heart rate variability. J Clin Sleep Med. 2013.
[7] Yoo SS, et al. The human emotional brain without sleep — amygdala reactivity study. Curr Biol. 2007.
[8] Haghayegh S, et al. Effects of passive body heating on sleep: systematic review. Sleep Med Rev. 2019.
[9] Scullin MK, et al. The effects of bedtime writing on sleep onset latency. J Exp Psychol Gen. 2018.
[10] Wright KP, et al. Circadian timing and light exposure. Curr Biol. 2013.