Is this the year you're going to run a marathon, cut out processed sugars and finally apply for that promotion you've been after?

If only you had enough willpower or self-control to see that plan through, right?

Wrong, according to clinical psychologist and adjunct professor at Georgetown University, Jelena Kecmanovic.

"A big misconception [about willpower] is this idea that if I would just be harder on myself, if I could beat myself up more, if I whip myself into shape … everything will be fine," Dr Kecmanovic said.

"And yet almost all the data shows the opposite."

Self-compassion more important than discipline

Rather, the research reveals that when you fall off the wagon — which you inevitably will, Dr Kecmanovic pointed out — showing yourself compassion is more helpful than beating yourself up about it.

What is willpower? Willpower is your capacity to engage in behaviours which are consistent with your intentions. It comprises three aspects: 1. Your ability to inhibit your response, or being able to say no to temptation 2. Being able to change your mind when circumstances change, for example, when you forget your really healthy lunch at home 3. Being able to think about the future consequences of your actions

Thinking in black-and-white terms about success or failure is generally not good for us, said health psychologist Barbara Mullan of Curtin University, and can actually lead to bad health behaviours.

For example, instead of having one unintended glass of wine you might end up binge drinking and finishing off the whole bottle.

"Whereas if you bring in a little bit more self-compassion, then you're more likely to say 'Yes, I had a bad day, I had a glass of wine that I wasn't planning on doing, but now I can stop'," Professor Mullan said.

You have to understand that changing your behaviour is actually quite hard, said Bernice Plant, a research fellow at BehaviourWorks Australia at Monash University, and setbacks can be part of the process.

"When you examine what you haven't [achieved], don't think of it in a negative way, but think about 'OK, what have I learned from that?'," Dr Plant said.

By far the biggest misconception is that people who are good at self-control are somehow robotic superhumans, Dr Kecmanovic said.

"This big misconception that self-control is something so internal, so intrinsic, that some people are just God-given better at it than others is also seen to be completely true," she said.

But while tests show people do have different amounts of willpower, she said new analysis suggests willpower isn't completely finite, nor does your store of it necessarily remain at a consistent level throughout your life.

Things you can learn from people who appear to have good stores of willpower

If you don't buy nacho chips at the supermarket, you won't be able to snack on them late at night. ( Pexels CC: Raizza Videna )

Break bad habits by first identifying the cues that trigger a behaviour you want to change, then reduce those cues, Professor Mullan said.

Rearrange your environment so you're less tempted by things you're trying to avoid, or the bad behaviours are harder to do or no longer possible, Dr Kecmanovic said.

For example, if you don't buy snacks when you go grocery shopping, you won't be able to eat them late at night.

Think about what you should be actively doing instead of focusing on the undesirable behaviour, Dr Plant said. It might help to figure out what's leading to that undesirable behaviour in the first place.

Make your goals meaningful to you

A trap people can fall into is setting goals that don't really fit them, so they aren't necessarily personally relevant, Dr Plant said.

"Good goals are going to be goals that express our personal interests and values," she said, "so it's very hard for someone to tell you what your goal is."

It can be helpful to identify the reasons why you want to achieve that goal, Dr Plant said.

What are some of the benefits it's going to bring you? This helps gives you the overarching purpose and direction behind what you're doing.

Connecting with the "why" also allows you to identify what personal values these goals are serving. Dr Kecmanovic likens values to directions in life and goals as a signpost in that direction.

If you clarify your values, then your goals may change — for example, if you discover you hate the cycling class you signed up for to get healthier you may decide to join a running group instead — but not the values they're in the service of.

Intrinsic motivation is better long term, but short-term extrinsic goals can be effective, Professor Mullan said.

The key then is to get people who have extrinsic goals to make them internalised.

"You might start off going to the gym because you want to lose weight … but you then discover that you just love spin class, it's absolutely your thing, and now you're going for internal motivation."

Other strategies you can use to boost your willpower

Joining a real life group of like-minded people can be a great way to help you stick to your goal. ( Unsplash CC: Geert Pieters )

Surround yourself with people who are doing what you want to be doing, Dr Kecmanovic said — whether they're people you're looking to as role models or people you're mentoring.

Online groups are fine, real life groups are better and your friends are even better than that.

"They are people you care about a lot, so if your friend is doing it you are 100 times more likely to do it," she said.

"You're going to disappoint yourself, you're not going to disappoint the other person."

Focus on how you're going to go about working on what you want to work on by creating "if-then" plans for your behaviour, so you know exactly what you're going to do in a particular situation, Dr Plant said.

"Focus on one goal, but that might mean actually tackling a couple of different behaviours."

Keep things achievable by looking at what you can currently do and work within your current range, she said.

"This idea behind this is to keep your confidence and your ability to change your behaviour high."

It's also a good idea to have a routine to reduce the amount of decisions you have to make, Professor Mullan said.

If you make one change and stick to it, it will be easier to make changes in other aspects of your life, Dr Kecmanovic said.

"[But] please, please, whatever you do in life, do not make five changes at once."