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The Science Behind Motivation: Intrinsic Motivation

Disclaimer: I am NOT a qualified professional. I am writing this from a position of someone, who used to study Biology and PE, with a curious mind. For more information, you can find MSBLife’s Disclosure and Privacy Policy here.


Motivation is something that everyone seems to be looking for. Whether that be motivation to work out or just to get out of bed. But, what is motivation and how does it work? I thought it would be interesting to do some research into the science behind motivation and answer 3 questions. What is it? What effects it? How does it impact physical activity?


Starting off with arguably the most important (or so we will find out!) variant – intrinsic motivation.

What is Intrinsic Motivation?

The definition of intrinsic is, ‘belonging to a thing by its very nature‘. (1) When you relate this to motivation it defines along the lines of, ‘the primary propensity of organisms to engage in activities that interest them.’ (2) (I had to google propensity too don’t worry)

So, we have a definition of intrinsic motivation but what actually is it? Intrinsic motivation is a motivation that comes from inside of you. It means you are motivated by how you feel whilst doing something. E.g. If you love the feeling of getting out of bed and opening your curtains every morning then you will be intrinsically motivated to get out of bed.

Me standing with curtains opening them in the dark showing my intrinsic motivation to wake up in the morning

(This is the opposite to extrinsic motivation – being motivated by external factors. But that’s a topic for another post!)

What effects Intrinisc Motivation?

Whilst I was doing research for this post, I came across many studies talking about the impact of various factors on intrinsic motivation.

The ‘Self-Determination Theory’ (SDT) is ‘a broad framework for the study of human motivation and personality‘. (3) Within SDT is a sub theory called ‘Cognitive evaluation theory’. (CET) This has the ‘aim of specifying factors that explain variability in intrinsic motivation.’ (4)

Me stood in front of a white background with question marks round my head symbolising all the factors that can impact intrinsic motivation

CET has four motions that impact the level of a person’s intrinsic motivation. These include choice and control over the process and the feeling of competence and optimal challenge. Studies suggest that when a person doing an activity feels controlled by an external factor then their level of intrinsic motivation decreases. Studies on children taking part in a challenge that enhances their competence suggest the same. (5)

Overall, this is suggesting that external factors can have a large impact on the effectiveness of intrinsic motivation. This also then provies a potential reasoning to why people have such varying levels of it.

How does Intrinsic Motivation impact physical activity?

From the research, you may have guessed that intrinsic motivation plays a significant role in getting people to take part in physical activity. In fact, there is a debate on whether it may be more significant than extrinsic motivation.

By looking at people in physical activity classes, Richard Fredrick researched the relationship between intrinsic motivation and exercise adherence. The studies concluded that ‘group differences in adherence were mediated by enjoyment motives. Body-focused motives were unrelated to adherence‘. The second study also added ‘adherence was associated with motives focused on enjoyment, competence and social interaction but not with motives focused on fitness or appearance.’ (6)

Me in a yoga pose laughing cause of my sense of enjoyment fuelling my intrinsic motivation
I don’t think this is how Yoga is supposed to be… Haha!

Although, a study by Andrea Ednie and Michael Stibor on undergraduates aged 17 to 42 on a health and fitness course suggests otherwise. ‘Enjoyment was rated lower than the other health, appearance and self-determined motives and only higher than… competition and social recognition.’ (7) However, it is important to take into account that the undergraduates were taking part in the course for extra credit. That itself is an external factor influencing their intrinsic motivation.

These varying conclusions suggest that maybe we haven’t got the influence of intrinsic motivation down to a ‘T’ yet. Some of the studies do have evidence for popular theories. This includes the theory that taking part in an activity because of enjoyment, as opposed to wanting to change your appearance, means you are more likely to adhere to it.

So, what can we learn from this?

It’s time to take what we have learnt on intrinisc motivation and relate it to our everyday lives.

You are more likely to continue participating in physical activity if you enjoy it. Therefore, if you are trying to start exercising then it is important that you pick an activity you actually want to do! If you love swimming, then why would you want to force yourself to go on a run?

The studies into CEF may also bring you a sense of security on those ‘off-days’ where you can’t find the motivation for the gym. A wide variety of external factors influence intrinsic motivation. Therefore, it is important that you develop your self-awareness on what influences it for you.

Me in Gymshark clothing in a pose with my foot in the air and arms up smiling to show my enjoyment fuelling my intrinsic motivation

Although, even if you do work out what may be decreasing your intrinsic motivation it doesn’t mean you will suddenly want to take part. Whilst exercising naturally releases endorphins, it still doesn’t mean that everyone will naturally want to exercise. Some people may need those external factors – or extrinsic motivation.

Therefore, next in this blog series ‘The Science Behind Motivation’, we will be looking into extrinisc motivation and answering the key 3 questions.


Hopefully, you enjoyed reading and learning a bit more about motivation! I would be grateful if you can leave your feedback and thoughts in the comments. I haven’t written a post like this before and I found it interesting so I am excited to get writing the next!

Until next time my friends!

-Millie 🙂


You can find all the references I used in this blog post HERE!

Pinterest graphic saying want to become more self motivated?

10 Comments

    • msblife28

      Thank you Megan! I found it super interesting to research and write about. I guess you fall into the category I mentioned at the end about needing external factors so watch out for my next one on extrinsic motivation hahaha!

    • Julie

      Hi Millie! I enjoyed reading this post – it made me think about motivation in a new light. And perhaps better ways to trick my body into being motivated. 🙂 I love the way you write too! You made what could’ve been dry and boring easy to read and understand.

      I’d definitely love to read more posts like this!

  • Chloe Osborn

    This was super interesting! I literally know nothing about the science behind motivation so this was really informative and I can’t wait for the next part! Thinking about it though it does make sense that if something makes us feel good we associate the action of getting up and doing it with positive thoughts rather than negative. I like how you put this into sections and italicised the quotes, it made it nice and structured!

  • Madi Dearson

    I LOVED reading this! this relates to where I am right now so much, it explains a lot. I have never been able to keep up with a work out routine before in my life. The real change happened when my body told me I need to do that. I just instinctively feel like I must do that now to feel good. Which is the only reason I can keep up with it (it is still not my preferred activity:)) but I also started to enjoy it which does make it way easier. I have realized long ago that listening to our instincts in all areas of life is usually the right choice:) GREAT post, Millie, really looking forward to the next.

  • Sophie Harriet

    This was really interesting to read! It makes a lot of sense that we are more likely to stick with activities we enjoy. But at the same time, if we don’t enjoy something but we know it is good for us, extrinsic motivation can play its part! I look forward to reading your next post on this subject 🙂

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