Stand-Up Paddleboarding in Oahu, Hawaii

Calories burned: Up to 1,000 per hour

Call to action: Yes, Matthew McConaughey and Jennifer Aniston look a bit silly propelling an oversize surfboard with a paddle in the pages of Us Weekly. But these svelte stars know that stand-up paddling (a.k.a. paddle surfing) blasts away calories, chisels arms, and carves a killer core. To get your own bod beach-ready, head for the hang ten capital of the world: Haleiwa, on Oahu's North Shore. Nate Kalani Burgoyne, an instructor with Rainbow Watersports Adventures, takes rookies up the Anahulu River to learn the basics—it's much easier than surfing, since you don't have to master the jump-to-your-feet part. After the two-hour intro on flat water, graduate to a session in the fabled waves of the North Shore. Dry off at Turtle Bay Resort, where you can talk up your new skills at the surf-side Hang Ten Bar & Grill.

The warm-up: All you need to know is how to swim. Rainbow Watersports teaches anyone older than 7 and weighing less than 250 pounds.

When to go: You can stand-up paddleboard on Oahu year-round, but May and June are ideal because of the low rainfall. Winter is a toss-up: You get big waves but also big crowds.

Two-hour lessons with Rainbow Watersports Adventures start at $79, including equipment; doubles at Turtle Bay Resort start at $237

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