If your New Year’s resolution revolves around getting fit and losing weight without dieting, you may be in for a tougher battle than expected. It turns out, just exercising alone likely won’t result in weight loss.

A study from Arizona State University, as reported by Cosmopolitan in 2014, studied 81 healthy women. For the test, the participants work out 30 minutes a day, three times a week for 12 weeks. Despite their rigorous workouts, the women, who were told to eat as they normally would during the experiment, did not lose weight. Instead, results showed that nearly 70 percent of the women gained weight during the study, with most of the weight coming from pure body fat.

So, what should those who want to lose weight do? According to Shawn M. Talbott, a nutritional biochemist and former director of the University of Utah Nutrition Clinic, it is easier for those wanting to lose weight to cut calories than to burn them off with exercise.

“As a rule of thumb, weight loss is generally 75 percent diet and 25 percent exercise,” Talbot told Huffington Post. “It’s much easier to cut calories than to burn them off. For example, if you eat a fast-food steak quesadilla, which can pack 500-plus calories, you need to run more than four miles to ‘undo’ it!... You can’t out-exercise a bad diet.”

While weight loss is better achieved by incorporating a healthier diet, it doesn’t mean you need to cut out all of your beloved foods out at once if you’re trying to shed a few pounds. “It does not have to be a complete revamp of someone’s way of eating since that is not typically sustainable,” Charlotte Markey, a diet and behavior expert at Rutgers University, told Scientific American in 2015. 

“But, in most cases, it has to involve dropping 300 or more calories per day; that can be done by dropping a couple sodas per day. People have to commit to this and prepare themselves—weight loss is a marathon and not a sprint.”

There are other things you can do to assist you on your weight loss journey. Healthline advises chewing your meals thoroughly without the distraction of electronic devices in order to slow down your food intake. Other tips include using smaller plates for unhealthier options to trim down portion sizes and drinking more water.