Rest days, the most unvalued part of training

By Dr Shiree Perano – Adelaide Women’s Health Coach

I get it, rest days are hard. I miss my exercise endorphins, I get grumpy with my husband and I snap at the kids. I’m just a big angry grey cloud. So why not just push through and train every day? There is a very simple reason, we need a rest day because this is when we actually get stronger, fitter and faster, and that’s what we all want right? 

How does that work you ask?

To understand how it works you need to understand the sympathetic and parasympathetic nervous systems.  The sympathetic nervous system is our response to danger, the fight or flight state, and it’s designed to keep us safe. The parasympathetic nervous nervous system is our rest, digest, repair and rebuild state. You cannot have both states active at the same time, you’re either in a sympathetic state or a parasympathetic state. 

As cavemen and cavewomen we predominantly lived in a parasympathetic state, relaxing by the fire and wandering around picking berries. The sympathetic state was only activated occasionally in times of danger, such as a tiger approaching or a scarcity of food

How does this work in today’s world?

Today most of us constantly live in a sympathetic state, which is activated by non-life threatening events such as running late, red traffic lights, sick kids, and work emails. Exercise also induces a sympathetic state, our body doesn’t know we are running for fun it just knows we are running so it thinks we must be in danger. 

When we are in a sympathetic state our body releases hormones, adrenalin, noradrenalin and cortisol, which activate physiological changes to support our survival. Our heart rate and blood pressure increase, pupils dilate, and blood is diverted from non essential organs, like the gut, to our muscles so we can run fast. Muscle repair and rebuilding is not a priority in this state and so it is down regulated. To make matters worse, to provide a continuous supply of glucose to fuel your escape from the tiger cortisol will break down muscle.

Therefore when we exercise we are actually breaking down our muscles. It’s not until we rest, and are in a parasympathetic state, that our body can rebuild, repair, and make the training adaptations.

So how do I optimize being in the parasympathetic state to get stronger, fitter and faster you ask?

Rest days are a priority, however reducing stress in general and activating the parasympathetic state is critical too. 

Ways to activate the parasympathetic nervous system?

  • Prioritise sleep before midnight as this is when our cortisol naturally drops and therefore our parasympathetic nervous system is naturally activated.
  • Take deep breaths into our belly as much as possible throughout the day. Deep breathing communicates to our body that it is safe, whereas shallow fast breathing communicates danger. 
  • Incorporate restorative practises into your day that help relax and calm you. For example reading, meditation, yoga, mindful walks, listening to music.


Written by Dr Shiree. A health coach, doctor, mum and triathlete who specialises in helping exhausted women increase their energy and balance their hormones so they can get back to the sports they love.  https://www.facebook.com/profile.php?id=100070906437267