Dressing for a fall outdoor workout can be a challenge. It’s usually a little nippy when I start out, then by mid-workout I’m ready to shuck a layer. But I’ve never been a fan of the tie-your-jacket-around-your-waist look, and I hate that flapping feeling. What’s a girl to do? To my rescue: the New Balance Lightweight Convertible Jacket, which converts easily from a jacket to a vest, thanks to removable sleeves.

I’m a sucker for a good workout jacket, and this one has all the key elements. It’s lightweight and soooo breathable, with stretchy, almost mesh-like fabric under the arms and along the neck and shoulder blades—in other words, the heavy sweat zones. Plus, there’s actual mesh down the center of the back, ingeniously covered with fabric in a way that keeps the wind out but lets air circulate.

It’s really cute, too, with a flattering cut and thumb holes at the ends of the sleeves—nice for when it’s chilly but not frigid enough for gloves.

Lastly, it offers groovy little extras like an iPod pocket and a bright yellow “in case of emergency” strip (with room to write your name, address, phone number, etc.) attached to the inside of one of the pockets, so you don’t have to worry about taking ID along.

Yes, that’s all well and good—but what about the sleeves, you ask!

While I’ll gladly acknowledge the versatility of being able to remove them—and be left with a fine-looking vest to keep my core warm—there are some drawbacks to the style.

The biggest one: The zippers that connect the sleeves to the rest of the jacket feel a bit uncomfortable under the arms, both with the sleeves on and off. It was also a little difficult—though doable—to unzip them while wearing the jacket.

Once I’d removed the sleeves, I stuffed them in the jacket pockets, as I’m sure I was meant to do. But that raised another problem: I suddenly looked like I was several months pregnant. This isn’t a huge deal, but I did feel I had some explaining to do when my husband caught sight of my newly rounded “belly” upon my return home.

So the jacket’s not perfect. Still, I do like the versatility, and this is truly the most breathable jacket I’ve ever worn. It may well remain my go-to jacket until winter arrives—or until word gets around the neighborhood that I’m “expecting."

Product: New Balance Lightweight Convertible Jacket

Category: Apparel

Pros: It's stylish, breathable, and allows you to switch from jacket to vest mid-workout.

Cons: The underarm zippers are a bit uncomfortable, and removing the sleeves while wearing the jacket is a little tricky. Also, the sleeves add bulk when stored in the jacket pockets.

Cost: $99.99 at NBwebexpress.com

Extra tips: Wear this over a short- or long-sleeve workout top instead of a tank or sports bra, so the zipper won’t irritate the skin under your arms. And keep track of which sleeve is which left and which is right, since the zippers are slightly different.