A hard session burns like a brisk walk — most of it is rest#
How many calories does lifting weights burn? For a typical 45-to-60-minute session, somewhere around 150 to 300 calories for most people — modest, in the neighbourhood of a brisk walk, and well under what steady cardio of the same length would cost. That surprises people, because a heavy session feels far harder than a walk. The number is low anyway, and the reason is structural: lifting is intense in short bursts and then you wait. You work for perhaps thirty seconds, rack the bar, and rest for two minutes. Averaged across the hour, all that recovery pulls the burn down to something ordinary.
So the calorie ticker is the weakest reason to lift, and this article is partly about why it is so easily misread — and mostly about what lifting actually buys instead. Because the payoff of resistance training was never the calories the session spent. It is the muscle you keep while dieting and the small, durable lift it gives the resting rate that dominates your daily burn. Judge lifting by the session ticker and you are grading a long-term asset on a single afternoon's cash flow.
The work is intense; the session is mostly waiting#
During the actual lifting, the rate is genuinely high. When researchers measured the oxygen cost of eight common resistance exercises, isolated moves ran between about 3 and 10 calories a minute at low intensity, and a hard half-squat set extrapolated to roughly 36 calories a minute at 80 percent of a one-rep max — the highest of any exercise tested — while an upper-body move like a biceps curl stayed near 8.51. Thirty-six calories a minute is a sprinter's rate. You simply cannot hold it: a set lasts seconds, and then you stop.
That is why the whole-session average lands so much lower. The MET values every calculator uses for resistance training already bake the rest intervals in — they are averages across the full session, not the peaks. The 2024 Compendium rates it as moderate work: 3.5 METs for a general multi-exercise circuit, 5.0 for squats and deadlifts, 6.0 for vigorous free-weight or powerlifting work2. Run those through a 45-minute session:
| Session (45 min, 70 kg) | Compendium MET | Gross kcal (our arithmetic) | Net of resting |
|---|---|---|---|
| Light circuit, 8–15 reps | 3.5 | ~184 | ~131 |
| Squats, deadlifts, explosive effort | 5.0 | ~263 | ~210 |
| Vigorous free-weight / powerlifting | 6.0 | ~315 | ~262 |
The MET column is the Compendium's; the kcal columns are our arithmetic — MET times body mass times the 0.75-hour session, with the net column subtracting the one resting MET you would have spent anyway. A direct measurement lands in the same place: 17 overweight women doing a heavy-load resistance session burned 289 ± 69 calories across 58 minutes, statistically no different from a BodyPump class3. A brisk walk burns like this too. The difference is that the walk did not leave you needing to sit down.
The number is fuzzier than any calculator admits#
There is an honest complication here that cuts against the low number, and it is worth stating plainly rather than pretending the figure is precise. Standard indirect calorimetry — measuring oxygen consumed — is built for steady aerobic work. Resistance exercise leans heavily on the anaerobic system, which does not show up in oxygen use during the set, so a review of the methods concluded that indirect calorimetry "is likely to underestimate the total energy expenditure of resistance exercise"4. The same review found reported multi-exercise sessions ranging from about 9 to over 700 calories (38 to 2,957 kJ), a spread driven by how many sets, how heavy, and how long you rest.
So treat any single figure as an order of magnitude, and one that probably runs a little low. That does not rescue the calorie case for lifting — a correction on a 200-calorie session is still a small number — but it is the truthful version: the session burn is modest and genuinely hard to pin down, and no wrist device is going to fix that when a metabolic cart can't.
The afterburn won't rescue it#
The usual reply is the "afterburn" — the idea that lifting keeps you burning for hours afterward, so the real cost dwarfs the session number. It doesn't. When a resistance bout was matched to an aerobic one for energy and the recovery burn measured, resistance exercise produced only about 27 calories of afterburn, and reviewers describe the weight-loss case for it as "generally unfounded" — the full accounting is in cardio versus weights for fat loss. Twenty-seven calories is less than a rounding error on the day, and nowhere near the hidden engine the afterburn story needs.
Where lifting actually pays: the resting rate and the muscle#
Step off the session ticker and the real returns appear — slower, quieter, and none of them on a single day's readout.
The first is a modest, durable lift in resting metabolism. Pooled across 18 trials, resistance training raised resting metabolic rate by about 96 calories a day versus controls — real, treated as a ceiling rather than a floor, and covered in full in does muscle burn more calories. Note what that means against the session: the daily resting bump from training consistently can rival or beat the calories any single workout spends, and it is working while you sleep.
The second, and larger, is what lifting protects during a diet. When you lose weight, some of what leaves is muscle — and resistance training plus enough protein biases the loss back toward fat and shields the lean tissue underneath, without changing how much total weight comes off (cardio versus weights; how much protein to build muscle). That preserved muscle is the floor under your resting rate, the tissue that keeps you strong and functional, and the thing a scale-only diet quietly strips. It never appears in a session's calorie count, and it is the entire reason to lift while losing weight.
Lift for what it keeps, not what it burns#
The practical read follows directly.
- Don't program lifting to burn calories. For pure energy expenditure, an equivalent stretch of cardio spends more, and neither is where a fat-loss deficit should come from anyway — set that from intake, not the workout.
- Don't eat the session back. A 200-calorie session that is partly compensated and partly mis-measured is not a licence for a 400-calorie reward; the leaky-ledger case is the pillar's.
- Lift for the muscle and the strength, especially in a deficit, and let the small resting-rate bump be a bonus you never have to count.
The calories a lifting session burns are real, modest, and beside the point. You are not buying a big number on the day. You are buying the tissue that keeps the number from falling later — and that trade only looks bad if you insist on grading it by the wrong meter.
FAQ#
How many calories does a weightlifting session actually burn?#
Roughly 150 to 300 calories for a typical 45-to-60-minute session for most adults — our arithmetic on the Compendium's 3.5-to-6 MET values for resistance training, and in line with a measured heavy session at 289 calories over 58 minutes. It is modest because the MET values already average in the rest between sets. The true figure is probably a little higher, since standard oxygen-based measurement misses the anaerobic contribution.
Why does lifting burn so few calories when it feels so hard?#
Because the hard part is brief. During a heavy set your rate can hit 20 to 36 calories a minute, but a set lasts perhaps thirty seconds and is followed by one to three minutes of rest. Averaged across the whole session, all that recovery pulls the burn down to moderate — around the level of a brisk walk. The intensity is real; the amount of time you spend at it is tiny.
Should I lift weights to lose weight, or just for muscle?#
Lift for the muscle. Resistance training is a weak calorie lever but an excellent way to keep the lean tissue a diet would otherwise strip, and it raises resting metabolism by a modest, durable amount (about 96 kcal/day across 18 trials). Set your fat-loss deficit from intake, and treat lifting as muscle insurance rather than a calorie-burning tool.
Sources#
- Reis VM, Garrido ND, Vianna J, Sousa AC, Alves JV, Marques MC. Energy cost of isolated resistance exercises across low- to high-intensities. PLoS One. 2017;12(7):e0181311.
- Herrmann SD, Willis EA, Ainsworth BE, et al. 2024 Adult Compendium of Physical Activities: a third update of the energy costs of human activities. J Sport Health Sci. 2024;13(1):6-12.
- Rustaden AM, Gjestvang C, Bø K, Haakstad LAH, Paulsen G. Similar energy expenditure during BodyPump and heavy load resistance exercise in overweight women. Front Physiol. 2020;11:570.
- Mitchell L, Wilson L, Duthie G, et al. Methods to assess energy expenditure of resistance exercise: a systematic scoping review. Sports Med. 2024;54(11):2955-2969.
