I think the 'seated' activity is something that covers all of your day. They come up with a number that would quantify all that energy expenditure, averaging out getting up from time to time, moving around, but basically not bursts of energy required by conventional exercise. Then when you add in sex, that takes some time (a small portion of all of the day is used for) out of that number. And perhaps it assumes 'lying down' - that can be a wrong assumption!). The average calorie expenditure for sex is going to be more than seated activity but it's also going to be brief and dwarfed by the total you already have - whatever you put in to describe your typical day. Except maybe if there was an option, 'lying still all day in bed'!
That's my guess. Someone else may come up with the explanation that is more factual!
Last edited by Kathy13118; 03-03-2014 at 06:06 PM.