It’s the third week of the new year, and many of us are realizing that those New Year’s resolutions are getting harder to keep. So TIME asked Roy Baumeister, professor of psychology at Florida State University and co-author of the bestselling book, Willpower for tips, gleaned from the latest scientific research, on how maximize self control, especially when you need it most.
What does energy and glucose — the fuel our bodies extract from food — have to do with willpower?
Self regulation depends on a limited energy supply. As you use it, [your willpower] gets temporarily depleted [as your energy stores fall], but if you use [willpower] a lot, your capacity improves [because you can change how you allocate your energy]. As the day wears on, people get worse and worse and more likely to give in to temptation. If you are spending a day at the beach, there may be no effect, but the accumulating demands of the day can really deplete you.
Is willpower in a sense finite, and its level dependent on energy? Or is there more to it than a biological process?
It’s more complicated than the early idea that it’s a matter of just how much [glucose] you had in your bloodstream. The body has a lot in storage and a number of other people are suggesting that it’s really more about allocating resources than about how much is active in the bloodstream.
There are a lot of things that can help you overcome [reduced willpower] when you are slightly depleted. Those who believe [that willpower is unlimited, for example] generally continue to perform well [in that situation].
But when people are more seriously depleted, belief in unlimited willpower actually may make things worse. A good analogy is physical tiredness. When you just start getting tired, believing you have unlimited strength or [that you] are superman can help you continue to perform well. But at some point, it really does catch up with you.
So if dieters are trying to avoid eating sugar, which turns into glucose, and self-control relies on glucose, are they doomed to fail?
Glucose doesn’t come just from sugar. Our advice for dieters is that it’s important to eat healthy foods first. That gives enough willpower to persist. If nothing else, it means you are somewhat full and even if you do eat some sweets, it’s not likely to be as bad.
You’ve found that making any type of decision— not just about whether or not to control a desired behavior— can sap your willpower.
Yes, after making a lot of decisions, your self control is lower and conversely, after exerting self control, your capacity for making decisions is lower. As you make a bunch of decisions, you gradually deplete the energy you have available and subsequent decisions are more passive and tend to go with the default option.
A study with Audi dealers [found that car buyers] were more effortful with their first few choices. [After that] they were more likely to take the default option, which can end up costing lot of money. They used up their energy deciding which of 200 interior fabrics they wanted and ended up buying lot of stuff they don’t need and spending extra money.
How do you conserve your willpower?
What you have to do is either save big decisions for when you are fresh— one piece of advice is don’t make big decisions on a Friday after a hard week. [Also] realize that you do deplete your energy and this changes your decision making process and realize how it changes. [There is] more avoidance, more taking the easy way out, more sticking with the default and status quo. All of those increase when people’s willpower is down.
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I read that President Obama only wears blue or grey suits so that deciding what to wear is one decision he doesn’t have to make. Is eliminating extra decisions a good strategy for improving willpower?
Yes. Obviously, the president has an exceptionally high number of decisions to make and needs to conserve his energy. Probably most people have set routines in the morning and that’s to conserve this energy. You don’t want to waste all your willpower making decisions about breakfast. That’s a good strategy and Obama is right: if you don’t have think about what to wear ever day, you don’t have to deplete your self control on that.
Does stress deplete willpower?
I have a research grant and am conducting a study right now. The assumption is that stress does deplete your willpower.
Are new tracking apps for fitness and diet useful in maintaining self control for dieting and exercise?
It’s very hard to regulate anything without keeping track of it. When the government wants to regulate something, it has to keep tabs on what [people or businesses are] doing. You could make a law but not look at whether [it’s being followed] but that probably will not produce as much compliance as if you audit and keep track.
Record-keeping itself is often a motivator. If you are trying to start exercising, it’s easy to say yeah I’ll exercise a lot. You don’t feel like doing it but you also don’t want to write down that you didn’t. You do that to make sure problems are recorded and to make sure you perform the behavior.
So how else can you maximize willpower?
In the short run, food and rest are the best things. In the long run, exercise seems to improve it.
And does it get better with practice?
Yes, metaphorically, it’s like a muscle.