Researchers say if you spend more time preparing meals, you may spend less time exercising, and vice versa.
The findings were revealed at the Population Association of America meeting.
They are based on time diaries that detailed how more than 112,000 Americans say they spent their time.
Every 10 additional minutes spent preparing food meant that men and women were less likely to exercise 10 extra minutes per day.
On average, Americans have less than one hour to spend on both exercise and food preparation, according to researchers.