# TDEE and maintenance calories explained for people who train > What maintenance calories and TDEE mean, how the Mifflin-St Jeor equation estimates them, and how to adjust from your weight trend without obsessing. Published 2026-11-13 · Updated 2026-11-13 · revns editorial **Maintenance calories** are the daily energy that keeps your weight roughly stable. **[TDEE](/dictionary/tdee)** (total daily energy expenditure) is the fuller picture: **[BMR](/dictionary/bmr)** at rest, plus movement, training, and the small cost of digesting food. Online calculators estimate TDEE with the **Mifflin-St Jeor equation** times an **activity factor**; the equation was derived from **498** healthy adults and is the usual default because later validation work found it closer to measured resting rate than older formulas. For people who train, the useful move is not memorising a number forever but **starting from an estimate**, eating enough **protein**, and **adjusting after two to three weeks** using a **7-day average weight trend**. **TL;DR** | Piece | What it means | | --- | --- | | **BMR / resting rate** | Energy at complete rest; largest share of TDEE for most people | | **TDEE** | Resting rate × activity factor (1.2 sedentary up to ~1.9 for heavy training) | | **Maintenance** | Eat near TDEE; weight trend stays flat | | **Fat loss** | Often **250–500 kcal/day** below maintenance → ~**0.25–0.5 kg/week** for many adults | | **Muscle gain** | Small surplus (**~200–300 kcal/day**) with progressive lifting and high protein | | **Reality check** | Do **not** add watch “burn” on top of TDEE; pick the **honest** activity level | Run your numbers in the [TDEE calculator](/tools/tdee-calculator), then cross-check protein with the [protein calculator](/tools/protein-calculator). ## What is TDEE in plain language? Think of your body like a car that idles all day. Even lying on the sofa, you burn fuel to keep your heart beating, lungs working and cells repairing. That idle cost is close to **basal metabolic rate (BMR)**. Add walking to work, lifting, fidgeting, digesting lunch, and a hard interval session, and you reach **total daily energy expenditure**. Researchers split TDEE into components: 1. **Basal or resting metabolism** — roughly **60–70%** of TDEE for sedentary people; a bit less when activity is high. 2. **Activity** — purposeful exercise plus **non-exercise activity thermogenesis (NEAT)**, such as stairs, pacing on calls and cooking. 3. **Thermic effect of food (TEF)** — roughly **10%** of intake to digest and process food; protein has a slightly higher TEF than fat or carbohydrate. You never see those buckets on a bathroom scale. What you *do* see is whether **average intake** is above, below or equal to **average expenditure** over weeks. ## How do calculators estimate maintenance calories? Most consumer tools, including revns, use **resting metabolic rate (RMR)** equations when lab measurement is unavailable. **Mifflin-St Jeor** is the default because it performed well across body sizes in validation work. ### The Mifflin-St Jeor equation For weight in **kilograms**, height in **centimetres**, and age in **years**: - **Men:** RMR = **10 × weight + 6.25 × height − 5 × age + 5** - **Women:** RMR = 10 × weight + 6.25 × height − 5 × age − 161 Example: a **30-year-old woman** at **65 kg** and **165 cm**: 10 × 65 + 6.25 × 165 − 5 × 30 − 161 = **1,396 kcal/day** (rounded) at rest. A **30-year-old man** at **80 kg** and **178 cm**: 10 × 80 + 6.25 × 178 − 5 × 30 + 5 = **1,778 kcal/day** (rounded) at rest. Mifflin and colleagues measured resting expenditure in **498 healthy subjects** (ages **19–78**, normal-weight and obese) and published the sex-specific formulas above. That is why calculators call the output an **estimate**, not a diagnosis—later studies still report meaningful error in some people, especially at extremes of age or adiposity. ### Activity factors The resting number is multiplied by an **activity factor** to approximate TDEE: | Label | Factor | Typical day | | --- | --- | --- | | Sedentary | **1.2** | Desk job, little deliberate exercise | | Lightly active | **1.375** | Light training or walking most days | | Moderately active | **1.55** | **3–5** days/week purposeful training | | Very active | **1.725** | Hard training most days or physical job | | Athlete / extra heavy | **1.9** | Twice-daily sessions or very demanding labour | Using the woman above at **1.55**: 1,396 × 1.55 ≈ **2,160 kcal/day** estimated TDEE. **Most people overestimate** activity. If your job is mostly seated and you train three evenings a week, **1.375–1.55** is usually more honest than **1.725**. When unsure, choose the **lower** factor and let the scale tell you whether to add food. ## What is the difference between BMR, RMR and TDEE? | Term | Measured how? | What it includes | | --- | --- | --- | | **BMR** | After an overnight fast, full rest, in a lab | Absolute minimum to stay alive | | **RMR** | Morning, rested, less strict protocol | Slightly higher than BMR; what equations approximate | | **TDEE** | Doubly labelled water in research; calculators use factors | RMR + all movement + TEF | In conversation, **BMR** and **RMR** are often used interchangeably on apps. What matters for your kitchen is **TDEE**: the number that, if eaten every day for a month, leaves weight flat. ## How do I use maintenance calories to lose fat? Fat loss needs a sustained **[calorie deficit](/dictionary/calorie-deficit)**: intake below expenditure. The scale moves slowly because **water, glycogen and gut contents** hide fat change for days. ### A moderate deficit that protects training NHLBI overweight-and-obesity guidance often targets a **500 to 1,000 kcal/day** reduction from usual intake for about **0.5 to 1 kg (1–2 lb) per week**, while very low intakes need medical supervision. For lifters, **250–500 kcal/day** below estimated TDEE is often enough for **~0.25–0.5 kg fat per week** without turning every session into a slog. Pair the deficit with: - **Protein** around **1.8–2.2 g/kg** if you resistance train ([protein guide](/blog/how-much-protein-per-day)) - **Progressive strength work** two to four days a week ([beginner strength plan](/blog/strength-training-for-beginners)) - **Sleep** in a range that keeps sessions productive ([sleep needs](/blog/how-much-sleep-do-you-need)) ### Why “3,500 calories = one pound” is oversimplified Early rules assumed **1 lb (0.45 kg) fat ≈ 3,500 kcal**. Kevin Hall showed that shortcut **does not fit every body** and that **changing body composition** alters how much deficit each kilogram lost needs—so real loss is often **slower than a straight-line calorie tally** predicts. Treat calorie math as **direction**, not a daily contract. If the **7-day average weight** is flat for **14 days**, intake is probably at maintenance, not deficit. ### Do not “eat back” exercise calories Watch and treadmill estimates of burn are noisy. TDEE multipliers **already include** your typical training. Logging food to maintenance **and** adding 600 kcal because a watch said so usually **double-counts**. Keep the same food target; adjust from **trend**, not from yesterday’s spin class. ## How do I gain muscle without excessive fat? Muscle gain needs **training stimulus**, **protein**, and often a **small energy surplus**. Many coaches use **~200–300 kcal/day** above maintenance while running a structured hypertrophy block. Larger surpluses raise scale weight faster but add fat unless you are a rank beginner. Practical checks: - **Strength** on main lifts trends up over **4–8 weeks** - **Protein** stays high; meals need not be “dirty” - **Weekly gain** much above **0.5 kg** for months may be mostly water and fat revns does not prescribe meal plans; use [meal tracking](/features/meal-tracking) to note **on-plan** meals and portion habits instead of counting every gram if that style suits you ([alternatives to calorie apps](/blog/myfitnesspal-cronometer-alternatives-without-calorie-counting)). ## Why can two people with the same TDEE lose weight differently? Equations ignore factors that shift real expenditure: - **NEAT** — some people unconsciously move more when overfed; others slow down when dieting. - **Sleep debt** — short sleep can change hunger hormones and food choices in controlled studies. - **Stress and illness** — temporary water retention masks fat loss on the scale. - **Menstrual cycle** — many women see **±1–2 kg** water shifts across the cycle; use monthly averages, not one pre-period weigh-in. - **Medication** — several drugs change appetite or resting rate; follow your prescriber’s advice. That is why **individual trend** beats arguing about 50 kcal in an app. ## What should you do this week? 1. **Estimate TDEE** with the [calculator](/tools/tdee-calculator). Pick the **lower** activity level if you are unsure. 2. **Weigh yourself** 3–4 mornings after the bathroom, before food. Record in notes or revns; ignore single spikes. 3. **Compute a 7-day average** after one week. Compare to the prior week if you changed food. 4. **Set protein first** at about **1.6–2.0 g/kg** if you train; fill remaining calories with mostly whole foods you already cook (dal, rice, roti, eggs, paneer, tofu, fish, chicken, vegetables, fruit, yoghurt). 5. **Hold the calorie target 14 days** before changing it. Adjust by **100–150 kcal** if weight trend is flat and the goal is fat loss (or gain). 6. **Log training and sleep** next to food if you use an AI coach ([mood and energy](/blog/how-to-track-mood-and-energy-next-to-training)) so deload weeks are visible. ### Vegetarian, vegan and mixed households Maintenance calories do not care about diet pattern. **Dal + rice**, **chole + roti**, **tofu stir-fry**, **eggs and toast**, or **fish curry** can all hit the same TDEE target; protein anchors matter more than the label on the diet. ## When should you see a professional? Get clinical advice before aggressive dieting if you have **diabetes**, **kidney disease**, **heart failure**, **pregnancy or breastfeeding**, or **a history of eating disorders**. Stop and seek urgent care for **chest pain**, **fainting**, **blood in vomit or stool**, or **rapid unexplained weight loss**. For mental health crises related to food or body image, contact a **qualified clinician or local crisis line**; an app or calorie target is not treatment. ## Related - [TDEE calculator](/tools/tdee-calculator) - [How much protein do you need a day?](/blog/how-much-protein-per-day) - [MyFitnessPal and Cronometer alternatives](/blog/myfitnesspal-cronometer-alternatives-without-calorie-counting) - [Strength training for beginners](/blog/strength-training-for-beginners) - [Meal tracking](/features/meal-tracking) This is general training and nutrition guidance, not medical advice. ## Sources - [Mifflin MD et al. A new predictive equation for resting energy expenditure in healthy individuals. Am J Clin Nutr 1990](https://pubmed.ncbi.nlm.nih.gov/2305711/) - [Hall KD. What is the required energy deficit per unit weight loss? Int J Obes 2008](https://pubmed.ncbi.nlm.nih.gov/17848938/) - [U.S. National Heart, Lung, and Blood Institute. Practical guide to overweight and obesity in adults](https://www.nhlbi.nih.gov/files/docs/guidelines/prctgd_c.pdf) - [U.S. Department of Agriculture and U.S. Department of Health and Human Services. Dietary Guidelines for Americans 2020–2025](https://www.dietaryguidelines.gov/) ## Questions ### What are maintenance calories? Maintenance calories are the amount of energy you eat and use in a day that keeps your body weight steady over time. In practice people estimate them as TDEE: resting metabolic rate plus the energy of daily movement, training and digesting food. ### How accurate is a TDEE calculator? Mifflin-St Jeor was validated in 498 healthy adults and is the equation most calculators use; later reviews found it closer to measured resting rate than older formulas, though roughly one in five predictions still miss by more than 10%. Total daily spend still varies with NEAT, sleep and stress, so treat any number as a starting estimate and adjust using a 7-day average weight trend. ### Should I eat back calories burned during exercise? Usually no. The activity multiplier in a TDEE estimate already includes your typical training. Adding smartwatch burn on top often double-counts and stalls fat loss. Keep the same calorie target and change it only if your weight trend is flat for two to three weeks. ### How big should a calorie deficit be? A moderate deficit of about 250 to 500 kcal per day often supports roughly 0.25 to 0.5 kg fat loss per week while keeping strength sessions productive. Larger deficits speed scale loss but raise hunger and muscle-loss risk unless protein and lifting stay high. ### Do men and women use the same TDEE equation? The same Mifflin-St Jeor structure applies, but the final constant differs: +5 for men and −161 for women in the published formula. Sex is one input; height, weight and age matter too. Anyone on gender-affirming hormones should treat the result as a rough start and lean on trend data. ### When should I stop counting calories? Stop or get clinical support if tracking triggers bingeing, restriction, fainting, rapid unexplained weight loss, or constant anxiety around meals. People with a history of eating disorders should not use calorie targets without a qualified clinician. --- Canonical: https://revns.com/blog/tdee-and-maintenance-calories-explained Index of everything: https://revns.com/llms.txt revns gives training guidance, not medical advice.