Cross-country hiking, for example, has an MET of 6.0 and burns about 387 calories in one hour.

But crank up your effort to a race pace 16 to 20 mph and you’ll torch around 773.

A vigorous Spinning class on an indoor bike can burn nearly as many, about 741 calories an hour.

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Spend 30 minutes at a vigorous pace and you’ll burn about 248 calories.

But don’t get complacent, warns Procida.

Golf

An hour of playing golfcarrying your clubs; no carts allowed!burns about 290 calories.

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Want to really rev up your calorie burn?

“It’s a crazy cardio workout.”

Jump Rope

Just 10 minutes of moderate jump roping burns about 107 calories.

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Paddleboating or Stand-Up Paddleboarding

Spending your weekend at a beach or a lake?

Rent a paddleboat and head out on the water with a friend.

You’ll burn around 129 calories in just 30 minutesall while sitting back and enjoying the scenery.

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(Just don’t forget your sunscreen!)

Looking for a more stand-up way to enjoy the bay?

Rent a paddle boardbasically an extra-large surfboard&mdashl;and a paddle.

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Rock Climbing

“Rock climbing probably uses more muscles than any other sport,” says Cummings.

You’ll burn about 161 on a leisurely paddle around the lake.

“Rowing is awesome because it uses so many big muscle groups,” says Procida.

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Cranking it up to 7.5 mph (8-minute miles) raises your burn to around 403.

“If you’re going to run all out, run for 30 minutes.

Another way to ramp up your burn without adding time?

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Add hills or stairs.

You’ll also burn about 226 calories during 30 minutes of slow and steady freestyle laps.

(Breaststroke and vigorous freestyle burns about 322.)

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A vigorous Vinyasa or Power yoga class, on the other hand, might burn about 432.

Cross-country skiing takes even more effort, and burns about 511 calories an hour.

Sex

Yes, it’s exerciseespecially if you’re on top!

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Getting busy with your guy can set your heart racing and will burn about 48 calories per 30-minute session.

Plus, studies show that having regular orgasms can help reduce stress, improve sleep and protect yourticker.

Not a bad backup plan on those days you have to skip the gym, huh?

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