While the long hours, stress and takeout meals that have fueled the health care debate have taken their toll on many Senators and their staffers (read: under-eye circles and a few extra pounds), Sen. Kirsten Gillibrand is looking better than ever.

[IMGCAP(1)]The New York Democrat has dropped at least 20 pounds and has looked trim, rested and downright “youthful— in recent weeks, HOH spies say.

Gillibrand spokesman Matt Canter tells HOH that his boss has been getting quite a workout of late. “She’s certainly been running around New York visiting every county in the last year,— he says. And he notes that she’s an “avid squash player— who has taken on some of her colleagues. In fact, she’s featured in this month’s issue of Squash Magazine (not, admittedly, on HOH’s usual reading list).

The mag reports that the Empire State Senator was co-captain of the women’s team at Dartmouth College and played regularly as a young lawyer, but she gave up the game when marriage, family and Congress took over her schedule.

But recently, she’s taken up her racket again and hits with Sen. Al Franken (D-Minn.), according to the story.

Sounds like she’s got the swing of things.

Get Your Sexy On. Forget that little black dress or seductive perfume. These days, Washington is all hot and bothered by energy-saving mechanical insulation.

First, President Barack Obama was seduced by the earth-friendly construction materials. But he’s not the only one confessing his undying love — Rep. Debbie Halvorson (D-Ill.) also declared her insulation admiration, sending Members of Congress a Justin Timberlake-inspired “Dear Colleague— letter titled “Insulation: Bringing Sexy Back.—

Pipes, water tanks and boilers: So naughty!

Obama shared his love for insulation — we think jokingly — during a speech at a Home Depot on Tuesday. There, the president urged Congress to pass incentives for homeowners who take steps to make their homes more energy-efficient and, in trying to sell his pitch, muttered: “Insulation is sexy stuff.—

Sex sells, after all.

Obama’s speech immediately drew the attention of Halvorson, a longtime admirer of the sexy construction materials, spokesman Ryan Vanderbilt told HOH.

Shortly after the president delivered his speech, the Illinois Democrat sent out her “Dear Colleague— letter, which pushes legislation that she introduced Friday to create a tax incentive to encourage the use of mechanical insulation in nonresidential buildings.

“Since coming to Congress, Rep. Halvorson has advocated for the benefits of mechanical insulation, the money it would save and the jobs it would bring — and like the president said, saving money while creating jobs is definitely sexy stuff,— Vanderbilt said.

Oh my … is it hot in here, or is it just us?

Legislation and All That Jazz. Rep. John Conyers is practically a living legend on Capitol Hill, but it turns out that if it wasn’t for a group of jazz musicians, the Michigan Democrat might not have ever wound up walking the halls of Congress.

Conyers appeared on the House floor Tuesday morning to speak about legislation that he introduced honoring the 50th anniversary of the classic jazz album “Kind of Blue.— And Conyers recounted his days as a youngster listening to the genre’s swinging sounds, noting that he once considered spending his life as a jazz musician.

“I studied music as a young person,— Conyers recalled. “I owe these musicians a debt of gratitude because it was they who recommended that I go to law school. So I’m grateful to them for helping my career.—

Guess Conyers will just have to settle for the minutiae of wonky policy over singing the blues.…

Overheard on the Hill. “I imagine further research was needed because no one remembered what happened.—

— Sen. John McCain (R-Ariz.) cracking up a crowd at the Heritage Foundation on Tuesday, as he complained about an earmark to fund studies of the trippy-hippie Woodstock music festival.

“Enjoyed by few, appreciated by many, questioned by all — yes, it’s that time of year. I’m making the rounds to deliver my fruitcakes.—

— Rep. Earl Blumenauer (D-Ore.), getting into the gift-giving spirit via Twitter on Tuesday afternoon.

Jessica Brady contributed to this report.

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