Fitness & Hormones: What Does Cortisol Do?

Nicknamed the “stress hormone”, cortisol often gets a bad rap. But cortisol plays such an important role in your overall health, influencing energy levels and regulating other essential bodily functions. We need it to survive! 

Understanding the functions of cortisol can help you recognise the positive and negative effects this hormone can have on your health and wellbeing, and empower you to make fitness and lifestyle choices to better support your body.

Find out: 

• What is cortisol?

• What does cortisol do?

• What happens to cortisol when you exercise?

• High cortisol symptoms

• Ways to lower cortisol levels

What is cortisol?

According to the Cleveland Clinic, cortisol is a hormone that is produced and released by your adrenal glands (located on top of your kidneys) to regulate your body’s response to stress.  Cortisol is an essential hormone and has a role to play in almost all of your bodily functions, organs and tissues. 

While your body releases cortisol at different times, it’s also monitoring your cortisol levels to maintain overall steady levels. It’s when your body remains in an ongoing state of stress and your cortisol levels remain high for a prolonged period of time that you can run into problems.

What does cortisol do? 

When people hear the word cortisol, they often associate this hormone with the body’s “fight-or-flight” response, which is triggered when a stressful event occurs and your body reacts by increasing your heart rate, blood pressure and muscle tension. After the period of stress or high alert has passed, that spike in cortisol should return to normal alongside your bodily functions.

While the stress response is definitely an important function of cortisol, there’s so much more to it than that! Cortisol also plays an important role in the regulation of blood sugar, blood pressure and metabolism, suppresses inflammation, and in maintaining your body’s circadian rhythm or sleep-wake cycle. 

During the course of an average day, your cortisol levels will fluctuate naturally, rising in the morning to help you wake up, lowering in the afternoon, and being at its lowest point in the evening as you wind down for sleep. It’s essential to have some cortisol in your bloodstream and daily fluctuations are healthy, but when your cortisol levels remain low or high for a prolonged period (such as when you’re experiencing weeks or months of ongoing stress), this can cause problems that affect your whole body. 

If you suspect your cortisol levels are consistently too high or too low, it’s best to see your health professional for further advice.

What happens to cortisol during exercise?

Exercise does cause your blood cortisol levels to rise, but it typically only causes a short-term spike. According to Harvard Health, exercise reduces the body’s overall levels of stress hormones like cortisol, while also releasing those feel-good endorphins.

Research from 2021 also explained that exercise can support healthy cortisol and stress levels, with evidence showing that the cortisol spike that occurs during intense exercise can reduce the stress response to any following psychosocial stressors. Working out can also help to regulate those daily cortisol fluctuations, helping you to sleep better. 

Where exercise and cortisol can become problematic is if you’re already under a significant, consistent amount of stress and are choosing to complete regular high-stress workouts, or if you’re participating in intense endurance training. 

Research suggests the repeated stress of intense endurance exercise is associated with elevated cortisol levels over time, and being in a routine that constantly alternates between high levels of stress in your daily life and workouts can exacerbate any cortisol issues.

High cortisol symptoms 

Concerned about your cortisol levels? It pays to know some of the symptoms of high cortisol, and reach out to your healthcare professional for advice if you’re worried or want a check-up. 

High cortisol can lead to reduced protein synthesis, which can inhibit muscle repair and cause weight gain, muscle weakness, high blood sugar or blood pressure, weak bones or excessive hair growth. 

When your cortisol levels remain high for a prolonged period of time, it can also halt or slow down bodily processes that the body doesn’t consider essential to survive an immediate threat - such as your metabolism and reproductive system. Not ideal! To make the most of your training and prioritise lifelong healthy habits, it’s important to take your stress and cortisol levels into consideration.

6 steps to lower your cortisol levels

Even if you think you can handle a high level of stress, it’s still important for your overall wellbeing to develop a healthy routine and take measures to manage stress and support healthy cortisol levels. These can include good nutrition, regular exercise (including restorative movement), sleep, breathwork and mindfulness. 

To support your health and help you get the most out of your fitness journey, here are some of the ways you can regulate your cortisol levels.

Regular exercise

Exercise can play an important role  in helping to manage stress and maintain healthy cortisol levels. Keep in mind, more isn’t always better, both in regards to duration and intensity. If you have been under prolonged stress in other areas of your life, restorative training styles can be the best exercise to reduce cortisol, such as yoga, Pilates, walking or low-impact training. It doesn’t need to be long — even 10 minutes can change how you feel. 

Try to set aside time to exercise several times each week, and choose forms of movement that will support and nourish your wellbeing. Your workouts don’t have to be lengthy or intense to be beneficial — so try to create habits you enjoy and fit in movement when you can.

Try doing your workouts in the morning

When it comes to cortisol, there are two reasons you might want to try morning workouts. Firstly, because exercise causes a short-term spike in cortisol, exercising in the morning can support your body’s natural cortisol fluctuations and energy patterns. 

The second reason is to avoid an evening cortisol spike that could potentially jeopardise quality sleep. For many people, evening workouts aren’t an issue as this spike is short-lived, but everyone’s bodies respond differently to exercise, and evening workouts can cause cortisol levels to rise when they should be at their lowest - not the best recipe for a good night’s sleep. The best time to work out is different for everyone, so don’t be afraid to experiment with your workout schedule and see how your body feels.

Sleep seven to nine hours a night

Getting 7-9 hours of quality sleep can work wonders for your stress and hormone levels. The tricky part is when you’re struggling to sleep well because you’re stressed. 

You can improve your sleep by creating a nighttime routine and taking steps to wind down before bed. This could include some gentle stretches, dimming the lights, practicing mindfulness or implementing a gratitude practice - all of which can help to reduce your stress and help you to relax before bed. 

Sleep is fundamental to good health, so if you’re consistently struggling to get a good night’s sleep, book in to see your GP for support.

Spend time in nature

Spending just 20 minutes connecting with nature can help lower stress hormone levels, says Harvard Health. The time of day or specific nature setting aren’t important, just get out there! Research has even shown that gardening is a great way to tick off this feel-good wellbeing box. 

Make time for rest and recovery

Adequate recovery between workouts is essential for keeping your cortisol levels within a healthy range over time. When you skip your rest days (please don’t!) or don’t allow enough time for recovery, you may find you hit a fitness plateau, struggle with fatigue or experience other symptoms of overtraining.

Meditation, mindfulness and breathwork

Meditation isn’t woo-woo - it’s strongly supported by science as being a beneficial practice for your health and can do wonders for your stress levels! A 2017 meta-analysis and systematic review found that meditating leads to reduced cortisol levels in a diverse range of populations. 

Another study from 2013 found meditation lowers cortisol levels in the blood, suggesting it can help to lower stress and may decrease the risk of stress-related diseases such as psychiatric disorders, ulcers and migraines.

If meditation isn’t your thing, research also backs the benefits of breathwork and diaphragmatic breathing for reducing cortisol levels, and there are plenty of easy ways to incorporate mindfulness into your day. Keeping a journal can help you to track how your new habits impact your overall wellbeing over time. 

Lower your cortisol naturally to improve your overall wellbeing

Your stress levels are an essential piece of the puzzle when it comes to your health, and implementing healthy habits will set you up for long-term success on your health and fitness journey. 

Always remember that exercise and fitness are just one part of a healthy lifestyle — nutrition, sleep and overall life balance are important for your wellbeing, too.