fistThe lure of cupcakes, chips, chocolate, soda, French fries and other greasy, gooey, yummy foods is already hard to resist.

However, research shows you’re especially drawn to comfort and junk foods during the second half of your monthly cycle–Week 3 and Week 4–due to progesterone, which revs your desire for calorie-dense treats in case you got pregnant during ovulation and are now eating for two.

So, what can you do when these cravings are super-hard to resist, but you don’t want to give in because you’re trying to lose weight or stay healthy?

Try making a fist whenever you’re about to cave in to a craving.

Sounds strange, but according to 2011 study in the Journal of Consumer Research, clenching any muscle–such as your hand, jaw or thigh–automatically pumps up your willpower, making it easier to resist temptation.

In fact, the researchers found this easy technique can bump up your willpower to reach all your health goals where you need to exert self-control, such as withstanding a bitter-tasting yet helpful medicine or summoning the motivation to work out.

How’s it work? Tensing a muscle, which is a physical act of willpower, sends a non-conscious message to the brain to amp up its self-control, the researchers explain.

There is one caveat, however: This trick works only at the moment when you’re making the decision to be healthy or not. Study participants who clenched a muscle beforehand depleted their willpower by the time they had to make their choice. So, put off flexing till you really mean it.