Say again? I’ll have to work how hard to work off Thanksgiving dinner?

You really want to know what it’ll take to work off Thanksgiving dinner? Let’s just say, you’d better cancel your plans to watch football after dinner or to go shopping on Friday (unless you plan to make it an aerobic affair): It could take you into the weekend to work off all that turkey, stuffing, gravy, mashed potatoes and pie.

In a bid to focus Americans on controlling their weight, the Food and Drug Administration has issued new standardized national rules on how calorie counts must be reported to consumers and by whom. Public health advocates, meanwhile, have embraced offering all manner of helpful and eye-catching logos to draw consumers’ attention to “better-for-you choices.”

But there’s mounting evidence that no form of consumer information conveys the potential effect of a food choice on one’s weight quite as powerfully as do “sweat equivalents.”

Sweat equivalents leave little room for self-delusion. They don’t require a hungry teenager at the corner grocery store to know how many calories a day she should be taking in or what percentage of that total a bag of potato chips represents. They simply say: If you eat this, this is how long you’d have to jog (or swim, or jump rope or play basketball) to work it off.

Simple is good. And in experiments, posting sweat equivalents powerfully steered consumers toward water over sugar-sweetened soda, pretzels over chips, salads over cheeseburgers.

In that vein, CoachUp, a service that connects athletes intent on stepping up their game with private coaches, last year shared a handy graphic showing the “sweat equivalents” of a typical American Thanksgiving dinner. I thought this year, I’d share it with you again.

The average American takes in 4,500 calories on Thanksgiving: That is a lot of turkey, stuffing, gravy, cranberry sauce, creamed onions, candied yams and pumpkin pie -- actually, about seven Big Macs’ worth of calories.

And here, culled from reputable sources on the energy expenditure of various activities, are a few of the activities you will have to engage in to work off the average American intake on Thanksgiving:

-- Run (or play basketball or football) for 7.7 hours

-- Cycle for 15 hours

-- Row (or hike) for 10.3 hours

-- Swim for 10.6 hours (or bowl for almost twice that long -- 20.6 hours)

Look, you may be looking forward to spending hours on the elliptical machine this weekend or have plans anyway to run a marathon -- or two. But if you want to limit Thanksgiving’s damage, you might try to alter what scientists call the “energy balance equation” (calories taken in versus calories expended in activity) a little on both sides: Don’t go back for thirds on Thanksgiving Day and plan a long hike or an epic game of flag football after the meal, and run the next day.

Happy Thanksgiving!

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