The first time Athline Clark of Kaneohe tried stand-up paddle surfing, she was hooked.

Now she has to get out to the ocean to paddle a few times a week or else she'll feel like a part of her life is missing.

“;It's addicting,”; she said. “;It's so refreshing and it's inspiring. You don't feel like you're working out.”;

And yet, stand-up paddling is a great workout for the full body, from your legs to your back, core and arms, according to Clark, 52, a water aerobics instructor at the YWCA.

She says it also helps with endurance, stability, balance and coordination. How much of a workout you get depends how hard you push yourself, how far you go and whether you choose to go upwind or downwind.

Her favorite part of it, though, is the camaraderie, and the marine life she sees out on the open ocean. While paddling, Clark has been accompanied by a pod of spinner dolphins, turtles and manta rays, and witnessed beautiful sunsets and stunning moonrises.

On weekends, Clark gets together regularly with a group of friends for distance-paddling sessions throughout Oahu. They have paddled from Lanikai beach to the Mokulua isles, Flat Island and Kailua Bay; from Sunset Beach to Haleiwa on the North Shore; and from Hawaii Kai to Kahala.

Stand-up paddling has made a comeback as a sport over the last few years but is also gaining traction as an everyday fitness trend.

It requires a surfboard, a paddle and other simple gear like a leash, but that's it.

Stand-up paddling can also be done in a wider ranger of venues because it doesn't require waves. It can be done on lakes and rivers, but if you're looking for some action, you can also surf the waves.

Carol Naish, owner of Naish Hawaii in Kailua, which has seen a significant jump in stand-up paddle-board rentals, says the sport appeals to a broader range of people than conventional surfing. Naish carries boards of all types.

It appeals to men and women of all ages and sizes, ranging from pint-size petite to larger individuals, as well as those who have back and knee problems that make it hard for them to get up from a prone position.

FOR THOSE WHO want to lose weight, the sport is a blessing. Just ask City Councilman Donovan Dela Cruz, who has dropped 60 pounds since he made stand-up paddling part of his overall fitness regime, along with a change in diet. Or longboard surf legend China Uemara, who lost 50 pounds after he started and now offers free lessons at Ala Moana Beach Park.

“;For a lot of our customers, it's a way of getting back in the water,”; Naish said.

Stand-up paddling is also gaining popularity among visitors. Practically every surf school now offers it, along with traditional surf lessons.

Girls Who Surf offers rentals and lessons in stand-up paddling to meet the demand, especially among international visitors, says owner Cherry Fu, who has had a growing number of clients from Japan to Europe and the mainland inquiring about stand-up paddling.

Reid Inouye, founder of Paddle Core Fitness and Standup Paddle magazine, launched classes specifically catering to those who want to get in shape through paddling at Ala Moana Beach Park.

He offers two programs: a 55-minute power workout for beginners that focuses on turning techniques, and an advanced burn workout focusing on race techniques. The workouts cost $15 per session ($10 if you bring your own board).

Inouye, 54, used to be a runner but now says stand-up paddling is his life. His first trek was from Hawaii Kai to Kahala on a 12-foot, 50-pound board shaped by Ed Angulo on Maui. He was hooked the minute he stood up on the board. He compares it to walking on water and says long-distance paddling gives him a cardiovascular workout while burning calories easily.

He took up the activity after his gym went belly-up in August 2006. He made a commitment to stand-up paddle from one end of Waikiki to the other as a way of staying fit.

“;I was totally exhausted every night from paddling for three hours a day, just about every day for a year and a half straight,”; he said. “;Almost an obsession.”;

But it paid off. He dropped from 235 pounds to 193 pounds — a loss of 42 pounds — in just three months. His blood pressure, which was high, dropped immediately.

With a schedule of 10-mile paddles and sprint races, Inouye now stays at a healthy 185 to 190 pounds, and he's getting ready to drop about 10 pounds more in preparation for the Molokai crossing.

His workout sessions have been popular among surfers as well as runners, triathletes and mixed martial artists. Inouye's son, Matt, a former professional baseball player, is now Paddle Core Fitness' lead instructor.

Inouye's classes teach isolation strokes that work everything from tricepses to shoulders, laterals, the lower back, abdominals and all the leg muscles. But most of all, he says, it works your brain.

Stand-up paddling is also good way to regain strength after an injury, according to Inouye. “;It's running without the pounding,”; he said.