Sex burns roughly 3 to 6 calories per minute, depending on how vigorous the activity is and your body size. For an average session lasting about 6 to 25 minutes, that works out to somewhere between 20 and 100 calories. The wide range explains why you’ll see such different numbers floating around online, and the real answer depends on factors that vary enormously from one encounter to the next.
What the Research Actually Found
The most-cited study on this topic comes from the University of Montreal, published in 2013. Researchers gave 21 young, healthy couples wearable sensors and tracked their energy expenditure during sex at home over several sessions. Men burned an average of 101 calories across a 24-minute session, which works out to 4.2 calories per minute. Women burned an average of 69 calories, or 3.1 calories per minute.
Those numbers sound reasonable until you consider the context. The participants were in their early twenties, physically active (exercising at least two hours a week), and averaged 24 minutes per session. That’s longer than most people. Other estimates using heart rate data and standard metabolic calculations put the average session at closer to 6 minutes, which would total only about 21 calories for a man in his early-to-mid thirties. That’s roughly 14 calories more than he’d burn watching TV for the same amount of time.
So the honest answer is: it depends heavily on how long the session lasts and how much physical effort you’re putting in.
Why the “100 to 300 Calories” Claim Is Wrong
You’ve probably seen claims that sex burns 100 to 300 calories per session. Researchers have specifically called this out as an obesity myth. The number likely originated from extrapolating peak exertion rates across an unrealistically long session. In reality, sex involves a mix of active movement, pauses, position changes, and varying intensity. Your heart rate during intercourse rarely exceeds 130 beats per minute, and on a perceived effort scale of 1 to 5, men in the Montreal study rated sex at 2.7 compared to 4.6 for treadmill exercise. It simply doesn’t feel as hard as a real workout, and the calorie burn reflects that.
How Sex Compares to Other Activities
The standard reference guide used by exercise scientists (the Compendium of Physical Activities) assigns sex a metabolic intensity value that varies by effort level. Vigorous, active sex gets a rating of 5.8 METs, which is comparable to moderate cycling or a brisk uphill walk. General, moderate-effort sex comes in at 3.0 METs, similar to slow walking. Passive activity like kissing and light contact registers at just 1.8 METs, barely above resting.
To put it simply: sex at moderate effort burns about the same calories per minute as walking. At its most vigorous, it’s comparable to a light jog. But jogging sessions typically last 20 to 45 minutes at a sustained pace, while the high-intensity portions of sex tend to come in short bursts. Harvard Health Publishing summed it up neatly: sex burns about five calories a minute, roughly the same as walking a golf course.
What Affects Your Calorie Burn
Several factors shift the number up or down:
- Duration. This is the single biggest variable. A 6-minute session and a 30-minute session produce very different totals, even at the same intensity. Foreplay, position changes, and breaks all count toward time but at lower calorie rates.
- Body weight. Heavier people burn more calories doing any physical activity, including sex. The Montreal study participants averaged about 154 pounds for women and higher for men.
- Level of effort. Being the more active partner matters. The difference between vigorous and passive effort is more than threefold in metabolic intensity.
- Position. Positions that require you to support your body weight or engage large muscle groups (legs, core, glutes) will burn more than lying on your back.
- Age and fitness level. The Montreal study used young, fit participants. Older or less active individuals may burn slightly fewer calories at the same effort level, partly because of lower muscle mass and cardiovascular capacity.
Is Sex a Realistic Form of Exercise?
Not as a replacement for actual workouts, no. Even in the best-case scenario from the research, a full session burns about as many calories as a 10-minute jog. Most sessions are shorter and less intense than what the Montreal study captured. If you’re counting on sex for weight management, the math simply doesn’t add up. Burning an extra 20 to 100 calories a few times a week is negligible compared to a 30-minute run (which burns 200 to 400 calories) or even a brisk 30-minute walk.
That said, sex does have real physical benefits beyond calorie burn. It raises your heart rate, engages multiple muscle groups, and involves bursts of moderate exertion. It’s physical activity, and any movement is better than none. It’s just not the calorie-torching workout that pop culture makes it out to be.