Women burn roughly 3 calories per minute during sex, which adds up to about 69 calories over an average session of around 24 minutes. That number comes from a study at the University of Quebec that tracked 21 young couples wearing activity monitors during intercourse. Men in the same study burned more, averaging 101 calories, largely because they tended to be more physically active during the encounter.
What the Research Actually Measured
The Quebec study remains one of the few to directly measure energy expenditure during sex using portable sensors rather than relying on estimates. Women in the study burned 3.1 calories per minute on average, with a standard deviation of about 1 calorie per minute. That means some women burned closer to 2 calories per minute while others hit 4 or more, depending on how active they were. The average intensity registered at 5.6 METs for women, which falls squarely in the “moderate intensity” category, comparable to a brisk walk or light cycling.
Heart rate data from a separate study published in the American Journal of Cardiology found that women’s peak heart rate during sex averaged about 105 beats per minute, reaching roughly 62% of their age-predicted maximum. Women in that study rated their perceived exertion at 2.5 out of 5. In other words, sex feels like mild to moderate exercise for most women, not an intense workout.
How Sex Compares to Other Activities
The physical demand of sex is roughly equivalent to walking a golf course, raking leaves, or playing ping pong. Harvard Health Publishing puts it at about 3.5 METs in terms of oxygen consumption, though the Quebec study measured it slightly higher at 5.6 METs for women. The difference likely reflects how active participants were during the encounter.
The 2024 Compendium of Physical Activities, a standardized reference used in exercise science, assigns sex three different MET values depending on effort level: 1.8 for passive activity like kissing and hugging, 3.0 for general moderate effort, and 5.8 for active, vigorous effort. That range helps explain why calorie estimates vary so widely. A 20-minute session could burn anywhere from 36 calories at a leisurely pace to over 100 calories at high intensity.
How to Estimate Your Own Calorie Burn
You can get a personalized estimate using a simple formula: multiply 0.0175 by the MET value, then multiply by your weight in kilograms, and finally multiply by the number of minutes. For a 150-pound woman (68 kg) having moderately active sex for 20 minutes at 3.0 METs, that works out to about 36 calories. At vigorous effort (5.8 METs), the same session jumps to roughly 69 calories.
To convert your weight to kilograms, divide your weight in pounds by 2.2. Here’s a quick reference for a 20-minute session:
- 130 lbs (59 kg), moderate effort: ~31 calories
- 130 lbs (59 kg), vigorous effort: ~60 calories
- 160 lbs (73 kg), moderate effort: ~38 calories
- 160 lbs (73 kg), vigorous effort: ~74 calories
- 190 lbs (86 kg), moderate effort: ~45 calories
- 190 lbs (86 kg), vigorous effort: ~88 calories
What Changes the Number Most
Three factors have the biggest impact on how many calories you burn: duration, intensity, and body weight. Duration is straightforward. The longer a session lasts, the more energy you use. But most research suggests the average sexual encounter lasts somewhere between 15 and 25 minutes including foreplay, which limits the total calorie opportunity.
Intensity matters more per minute than duration does. Being on top, actively moving your hips, or switching between positions all increase the physical demand. A passive role burns closer to 1.8 METs, while actively driving the movement can push past 5.8. That threefold difference in intensity translates to a threefold difference in calories burned per minute.
Body weight plays a consistent role because it takes more energy to move a heavier body. A woman who weighs 180 pounds will burn roughly 30% more calories than a woman who weighs 130 pounds doing the same activity at the same intensity, simply because her muscles are working harder against more mass.
Why Sex Isn’t a Reliable Workout
Burning 69 calories in 24 minutes isn’t nothing, but it’s far less than most structured exercise. A woman burns about 150 to 200 calories in 30 minutes of jogging, roughly triple what sex provides in the same timeframe. The intensity of sex also fluctuates constantly, with bursts of effort followed by rest, which limits sustained calorie burn compared to continuous exercise.
That said, sex does provide real physiological activity. Your heart rate rises, your muscles engage, and your body consumes more oxygen than it does at rest. It counts as light to moderate physical activity, and for people who are otherwise sedentary, it contributes meaningfully to daily energy expenditure. It just shouldn’t replace your regular exercise routine if calorie burn is the goal.