It’s easy enough to get a calorie count on the food we eat. But it doesn’t mean much to many of us according to a new report in the American Journal of Public Health. The researchers say showing people how much activity they would have to do to burn those calories off might be a better way to convince us to change our eating habits.

In a novel experiment, they posted different types of signs around six stores in Baltimore. One posted the number of calories in a regular bottle of soda. Another posted the amount of sugar in the same bottle. A third type of sign showed either the number of minutes someone would have to run or the number of miles they would have to walk to burn off those 250 extra calories.

The study authors found that signs that displayed the physical activity information had a stronger effect than the others, and induced more people to opt for alternatives like water.

And no wonder: everyone burns calories at a different rate but for example a 165 lb woman would have to jump rope for 45 minutes to work off two slices of pepperoni pizza. For a 20 ounce regular soda, it would take 20 minutes of jumping jacks. Similarly, a 195 lb man would have to do 50 minutes on a stationary bike to burn off 1 fried chicken breast and two wings.