Exercise is transformative. Along with nutrition, exercise is one of the most potent tools available. It can near instantaneously transform mood.
It changes your physiology, neurochemistry and neurobiology, the expression of your genes, your mood, your state, your thinking.
Table of contents
How exercise transforms mood
Exercise changes your physiology and results in a stress response. This is a positive stress response – it causes the body to adapt, respond and get healthier and stronger.
When the body undergoes stress or experiences pain, part of this response is to alter its production of certain proteins, chemical messengers (hormones) and brain chemicals (neurotransmitters).
Key proteins and neurotransmitters associated with mood
Brain derived neurotrophic factor (BDNF): a protein associated with mood changes, neuroplasticity, memory, stress resistance. Reduced levels are associated with depression (1), neurodegenerative diseases, aging and chronic stress (2).
Serotonin: a neurotransmitter associated with mood, of which altered levels are associated with depression and anxiety (2,3).
Dopamine: a neurotransmitter associated with pleasure and the reward system (4).
Endorphins: a neurotransmitter associated with the inhibition of pain and sense of wellbeing and euphoria (5).
Endocannabinoids: neurotransmitters associated with pleasure perception, mood, and emotion (6,7,8,9).
Kynurenine: an amino acid that can either be metabolised to a neuroprotective product or a neurotoxic product. The neurotoxic product, quinolinic acid is associated with depressive behaviour (10).
Neurochemistry is very complex and levels of neurotransmitters all influence one another…..
What does the research say about exercise and mood?
Increased levels of BDNF: analysis of over 29 studies shows that exercise increases levels of BDNF (11). Levels of BDNF are indicated to increase from both exercise intensity and regular exercise (11).
Increasing levels of BDNF may be particularly relevant to anyone who suffers from low mood, depression or anxiety (1). Because BDNF is associated with neuroplasticity (12), increasing levels may be especially helpful for individuals who have a tendency to become obsessive (13) and/or get stuck in a cycle of repetitive thoughts.
Boosting BDNF levels may also be particularly helpful for those suffering from stress, aging, or declining in cognitive function (2).
Altered levels of neurotransmitters: a number of studies indicate that exercise influences a change in the synthesis and metabolism of noradrenaline, serotonin and dopamine (14).
Dopamine levels are seen to increase following exercise (5). Other neurotransmitters indicated to increase from vigorous exercise are glutamate and GABA, indicated to be depleted in individuals with depression (15).
Increased levels of endorphins: exercise significantly increases levels of the endorphin known as an opoid (5). Endorphins also increase levels of dopamine (3).
Increased levels of endocannabinoids: exercise significantly elevates endocannabinoid levels, associated with improved mood states, reduced pain sensitivity, reduced anxiety and increased motivation to exercise (6,7,8,9).
Less production of neurotoxic products: endurance exercise is associated with shifting the metabolism of the amino acid kynurenine so that less of the neurotoxic product is formed (16).
Mood changes associated with exercising
The high: euphoria, wellbeing, pleasure, enormous satisfaction. The body’s response to stress is to release endorphins and endocannabinoids, as a natural pain relieving strategy. Ever noticed that some of those most challenging workouts leave you with the biggest high? This is your body responding and adapting to the challenge of the workout.
Within reason, longer durations and higher intensities have a greater effect on this high – but more about that later.
Presence: when you’re exercising it forces you to be present. Whether you’re focusing on mastering the movement, following the sequence or rising to the challenge – it requires your undivided attention. With presence comes space, escapism, immense joy, liberation from the mind.
Strength: I’m not talking about physically stronger but mental and emotional strength or call it resilience. You feel better equipped to meet whatever comes at you that day.
What problem? Ever noticed that pre workout you have loads of “problems” and post workout you don’t remember what the problems are? Problems are constructs of the thinking mind. Taking a break from the thinking, creating space from presence and reducing mind momentum, whilst increasing your flexible thinking with increased BDNF levels – voila, no problems.
The release: whether it’s stress, anxiety, work, personal – exercise is an opportunity to get it all out and let it go. Maybe it’s temporary, maybe it’s for good. But it’s an opportunity to begin becoming open to letting it out and letting it go.
Clarity: indecision or confusion about what is the best option…… Research shows that making more complex decisions is better undertaken without attention, with unconscious thinking (17).
Calm: that sense of peace and calm post workout. Like you can truly relax. From utilising your amazing body.
Accomplishment: the sense of completing something. Maybe it felt hard. Maybe you mastered something. Maybe you connected with your body. Maybe you simply moved. You feel good. I don’t think that’s about fitness, I think it’s about showing up, for you.
Energised: feeling tired pre exercise and energised post exercise? Likely a combination of the physical processes that take place during exercise, changes to levels of hormones and neurotransmitters along with being able to shake off problems, feelings and whatever else has happened that day/week – leaves you feeling lighter, less fatigued and more energetic.
How does the type of exercise impact mood?
The good news is that all exercise helps to improve mood. Two large scale reviews of multiple clinical trials – 30 trials in each review – show that both aerobic and resistance exercise have a large and significant effect on depressive symptoms (18,19). The exercise included in the reviews were either aerobic, resistance or mixed – yoga/tai-chi/similar relaxation movement was not included. Aerobic exercise was shown to have greater effects on depressive symptoms than resistance exercise.
A large scale trial focusing solely on resistance exercise still showed resistance exercise to significantly reduce depressive symptoms (20). Its effects were shown to be greater when individuals trained at a higher intensity and/or had a trainer (20,21).
Experiencing a certain high and more dramatic mood changes (so greater alterations in levels of proteins and neurotransmitters synthesised) is associated with higher intensities of exercise which may be harder to achieve with resistance exercise alone – you’d need to intersperse it with intervals of cardio and make the training more explosive.
A very large scale study of over 1.2 million people showed team sports to have the strongest associated improvements in mental health, followed by cycling, running and then gym exercises (not utilise machines such as treadmills) (22).
From my experience, working out as part of a group definitely leads to a heightened sense of euphoria and wellbeing – perhaps having a shared goal, purpose or simply the collective energy of being together. Research shows that working out in a group significantly improves stress levels and quality of life, whereas individuals working out alone don’t see the same benefits (23).
How does the intensity of exercise impact mood?
As stated, higher intensities of exercise are associated with greater changes in levels of proteins and neurotransmitters made. For example, a comparison of high intensity interval training (HIIT) versus less demanding physical activity showed that the HIIT group experienced a significantly greater increase in endorphin release (5) – this is that high feeling.
However, the moderate group still experienced sensations of pleasure and euphoria (5). It is individual and some people may have stronger associations with the negative feelings of doing a properly tough workout, whereas others will have a stronger association with the overall positive high.
Some changes in brain chemistry may only take place at certain exercise intensities, causing a shift in what is metabolised and therefore what is synthesised. One study showed that exercise intensity over >85% VO2 max, (HIIT) resulted in increased neurotransmitter production of glutamate and GABA (15). A large scale review of studies also shows that anaerobic exercise is associated with greater mood improvements (24).
Levels of BDNF are significantly greater at higher intensities than lower intensities of exercise (25,26). One potential mechanism hypothesised is that reactive oxygen species induce BDNF synthesis, more of which would occur at higher exercise intensities (27). Experimental evidence also indicates that BDNF may be induced through lactate production, which again would only occur at exercise intensities above 80% max HR (28).
In addition to stronger increases of BDNF at higher intensity exercise levels, there are greater increases in the neurotransmitters dopamine and adrenaline from 3 mins of anaerobic sprinting versus 40 mins of low impact running (29). Another study concluded that vigorous intensity (> 80 max heart rate) and long duration (40 mins) exercise offer the greatest probability of a significant increase in BDNF (30).
However, although moderate to high intensity is associated with greater mood improvements, this doesn’t mean that this is the optimal choice for exercise on a daily basis. There are other considerations and the body and mind require different stimuli, different intensities of exercise and recovery – even if the mind tells you otherwise! All of these factors will influence mood in the longer term too.
The good news is, even 10 minutes of moderate intensity exercise is enough to start changing your mood (24)!
How much exercise?
A large scale cross sectional study on over 1.2 million individuals, assessing the associations between exercise and mental health showed that exercising for 30-60 minutes, 3-5 times a week was “best” for improving mental health (22).
Exercising greater than 90 mins per workout was associated with small reductions in mental health (22). However, due to the nature of the study, it is likely that some exercise may have been unaccounted for and there will have been differences in reported exercise. But the results overall seem pretty reasonable to me – what do you think?
How transformative exercise is for you and which type is best will ultimately depend on you…..
Research shows that variation in certain genes are associated with differing responses in mood changes from exercise. One study showed that individuals with a more elevated reward system, and greater symptoms of depression, benefited more from aerobic exercise (31).
Another study analysed certain genetic markers that may predispose individuals to depression showed that those with the BDNF gene variant saw the greatest decreases in depressive symptoms from exercise, followed by those with the serotonin transporter gene variant (32).
Your mood to begin with
Some research indicates that the lower your mood, the more you may benefit from exercise, which does theoretically make sense – if exercise helps with your mood. One study showed that there was a significantly larger reduction in depressive symptoms from individuals scoring higher with depression (20).
Also, individuals with lower BDNF levels (associated with depressive symptoms) seem to benefit from greater increases in BDNF levels during exercise and a greater increase in intrinsic desire to further exercise, than individuals who had relatively higher BDNF levels pre exercise (33).
Please note I make no generalisations about depression and exercise – there is evidently variation in the mechanisms underlying depression and its cause for different individuals, which will naturally result in different treatments being beneficial for some and not others.
Changing your mood regularly and sustainably is more likely to occur and be effective when it comes from a place of joy. And consistent exercise is indicated to have a progressive effect on transforming mood (11).
Going with what you enjoy, including some variety and keeping an open mind is always helpful!
Whilst this article has largely focused on a state of euphoria, pleasure, improved wellbeing, reduced anxiety etc, the transformation you experience from exercise will vary depending on where you are that day, what you’re going through and what you need.
Ultimately your experience and perspective will change day to day – and not attaching to any one particular training session can help you to be all that more present.
My top tips for optimising exercise for your mood:
Am I wrong in saying that any short-term discomfort is completely and utterly outweighed by the ridiculous benefits from exercise?
How does exercise transform YOUR mood? What do you think I have left out? Thank you for reading and i’d be so grateful to hear your thoughts below in the comments!