This depends on how much you already know about your resting metabolism and what you’re trying to accomplish.

Personal Use: If you’ve never measured your resting metabolism before, we recommend measuring 2-3 times to understand your personal range of resting metabolism values.

If you are on a reduced-calorie diet, we recommend measuring at least once a week.

When you test the long-term effects of sustained exercise or athletic/endurance training, track changes by measuring resting metabolism at least once a month. This gives a long-term look at how the exercise or training program impacts resting metabolism. Research has shown that sustained exercise increases resting metabolism over time (see diagram below).

Effects of sustained exercise and physical activity (PA) on resting metabolism (REE). Figure adapted from: J. Speakman and C. Selman, “Physical activity and resting metabolic rate,” Proceedings of the Nutrition Society, vol. 62, pp. 621–634, 2003