Hawaiian surf instructors started using outrigger paddles so they could stand on their longboards and take pictures of surfing tourists.Reid Inouye of Standup Paddle Magazine

In the 1960s, Hawaiian surf instructors started using outrigger paddles so they could stand on their longboards and take pictures of surfing tourists, according to SUPglobal.com. Stand up paddleboarding, or SUP, came to California in 2000 and spread quickly from there. Today, the sport is popular on lakes, rivers and ocean beaches from Boston to Minneapolis to San Diego.

Instead of paddling while tummy down, SUP enthusiasts stand on large buoyant boards and maneuver with long paddles. The easiest way to start is on calm, flat water. As you get hooked, turn to forums like SUPConnect and SUPglobal to become part of local an international SUP communities.

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Paddleboard surfing offers a better view of incoming waves.Reid Inouye of Standup Paddle Magazine

When glassy water gets boring, it may be time to hit the waves. One advantage of stand-up paddleboard surfing is that it offers a better view of incoming sets. Another bonus: SUP circumvents the effort and physical strain required to repeatedly shift from belly to feet and back again. And even if the waves fizzle, there's still fun to be had.

Compared to lake paddling, though, there's more skill (and courage) required to hit the waves. Tower Paddle Boards, a manufacturer and shop, offers a long listof companies that offer SUP surfing lessons in states from California to North Carolina and in countries from Indonesia to Mexico.

Praticing yoga poses on the water requires more core strength.Reid Inouye of Standup Paddle Magazine

It's not hard to balance while standing on a floating paddleboard. But it will take a little more core strength to practice yoga poses on the water -- and stay dry.

"The stability of the paddleboard gives you the opportunity to relish your practice and embrace the beautiful surroundings of nature," explains Stand Up Surfing Magazine.

"The board is essentially your floating yoga mat where the body finds its natural alignment. Linking into the breath, movements are enhanced, deepening the experience physically, mentally and spiritually."

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Paddleboards are like a new kind of outdoor gym.Standup Paddle Magazine

Simply paddling a stand up board works out a variety of muscle groups, especially your core. For many people, paddleboards are like a new kind of outdoor gym -- a scenic spot to challenge your body in new ways.

SUP fitness classes abound. Pick fitness and sculpting classes, camps or boot camps at places such as SUPCore Academy in a variety of locations, San Diego's PaddleFit, the SURFIT Wahine Warriors Class, Nikki Gregg's Stand Up Paddle Boot Campsor a similar program in Vancouver.

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A long-distance paddleboard race.Standup Paddle Magazine

When another paddle around your local lake seems too short, it may be time to turn to long-distance SUP. Ambitious stand up paddleboarders have crossed the English Channel, paddled the length of the Mississippi and gone from Florida to New York.

Last year on Canada's Yukon Territory, paddler Ben Friberg set a record by covering 238 miles in 24 hours.

It takes strength of both body and mind to paddle for hours on end, wrote long-distance stand-up paddler Shane Perrin, who paddled more than 900 race miles in 2012, according to a blog post on PaddleBody.com.

"In endurance paddling the physical aspect is the easy part of the race," he wrote. "Your heart rate screams, muscles engage, the lactic acid builds up in your body, and you feel like you want to puke. This all passes after an hour or so and your body falls into line. Then comes the fun stuff like numb toes, cramps, and blisters."

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The paddleboard race calendar is full of options around the world all year long. Standup Paddle Magazine

Racing is another option for stand-up paddlers who feel fit and eager to compete. The race calendar is full of options around the world all year long. Many races take place as part of bigger events, like the TA-HOE NALU Paddle Festival on Lake Tahoe or the Molokai-2-Oahu Paddleboard World Championships. SUPTheMag.com offers an extensive race calendar.

There are plenty of opportunities for guided tours on paddleboards.Standup Paddle Magazine

For a tamer SUP experience, there are plenty of opportunities for guided tours through beautiful places.

You can travel by SUP along Montana's Clark Fork River, through forests and rivers in Puerto Rico, and over coral reefs in Tavarui, according to an article on SUPTheMag.com. Many SUP tour companies offer lessons on technique and fitness classes, along with a mix of other sports.

Find a list of tours on the Tower Paddle Boards site.

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Forget about getting fit on a paddleboard. Consider catching fish, instead.DEEP CREEK VENTURES

Forget about getting fit on a paddleboard. Consider catching fish, instead.

You might want to look into some specialized gear for this niche sport. To facilitate fishing, it can help to have screw-in attachments and deck organizers for gear, like the SUPerFISHal.

You might even want a platform to give you an extra lift off the water.

Some boards are inflatable, making them convenient for camping and fishing trips, according to BoardFisher.com.

SUP fishing has three major advantages over kayak fishing, explains Field and Stream.

"Because you're standing, you get to see more of the water you're fishing, including more of what's under the surface. This makes them an excellent choice for sight fishing," the article says. Standing up also provides a greater range of motion for casting and stand-up boards are light and easy carry around or check onto a plane.

"Drawbacks? Light breezes will blow you all over the water, so they're best in sheltered spots or days when there's very little wind."