MariposasTDEE (Total Daily Energy Expenditure)
TDEE stands for Total Daily Energy Expenditure, and it represents the total number of calories your body burns in a 24-hour period across everything you do: keeping your heart beating and lungs breathing (your basal metabolic rate), digesting food, moving around during daily life, and any deliberate exercise. It's the number that sits at the center of almost every body composition goal, because whether you're trying to lose fat, build muscle, or stay at your current weight, your calorie intake relative to TDEE is the primary lever. The part most people underestimate is that exercise typically accounts for only 15 to 30 percent of TDEE for most non-athletes; the bigger, more stable chunk is your resting metabolism and what researchers call NEAT (non-exercise activity thermogenesis), which covers fidgeting, walking to your car, doing chores, and every other incidental movement. The common mistake is treating TDEE as a fixed number you calculate once and trust forever. Your body adjusts its energy output in response to changes in weight, diet, and training load, so someone who has been in a calorie deficit for several months will often have a meaningfully lower TDEE than a formula would predict for their height and weight. Online calculators give you a reasonable starting estimate, but real-world results over two to four weeks of consistent tracking are what tell you where your actual TDEE sits.
Example
A 170-pound person with a desk job who lifts weights three times per week might have an estimated TDEE of around 2,600 calories per day. If they eat 2,100 calories consistently and their weight drops roughly half a pound per week over a month, that real-world feedback confirms their actual TDEE is close to that estimate. If nothing changes on the scale, they'd know their true expenditure is closer to 2,100, and they'd need to adjust accordingly.