Japanese underpants burn calories in your crotch

Odd one out. Calorie Shaper Pants -- definitely not aimed at creeps.

Regular exercisers will know all about the value of “feeling the burn” when pushing through the pain barrier, but perhaps not so much about the range of underwear from Japan that actually does the work for you and burns calories in your underpants. Really.

The concept of “functional underwear,” as aficionados know it, isn’t new, but its popularity is, with more manufacturers cottoning on to the power of marketing underwear that supposedly does the exercise for you.

Beer burn

Foremost among them is Shibuya-based Goldwin, which advertises its MXP Calorie Shaper Pants based on how much beer they allow wearers to burn off. Again, really.

The undershorts -- prices start at ¥2,940 -- feature an elastic resin printed on top of normal fabric in a honeycomb pattern.

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Goldwin’s scientists say the extra burden imposed on muscles by having to stretch the resin to simply move forces them to burn extra calories.

In fact, they claim a 65-kilo man walking for 90 minutes a day can go through an additional 210 calories a week -- that’s sufficient to burn off half a liter of beer.

Gender inequality

For a slightly smaller woman, however, the panties aren’t in quite such a bunch -- she gets to reward herself with a mere 350-milliliter can of suds.

Bonus fact -- another attribute of the magic underwear is its ability to “absorb the body odor of middle-aged and elderly men,” something Goldwin says it might dial down when advertising to women.