Hello," a middle-aged woman says curiously as she appears in the sunlight streaming through the large, open garage. "Is this the dog Jazzercise place?" she excitedly asks.

Close, but not quite. The Rex Center, located on the auto-repair-shop-lined Palmetto Avenue in Pacifica, looks like an auto mechanic's shop--and even gives the impression of one with a sign that reads "Pacifica Muffler." However, it is actually a soon-to-be sanctuary where massages, acupressure, aromatherapy, and warm water swimming will be exclusively available to all tail-wagging, face-licking, and quadrupedal kind.

Created by raven-haired San Francisco resident Cathy Chen-Rennie, The Rex Center is like the local community swimming pool for dogs, with an emphasis on health and fitness.

Chen-Rennie, a senior product manager at a Redwood City software company and former Google employee, will be conducting assisted swimming in a heated swim spa in much the same way a canine physical therapist would--but don't refer to her as such. She doesn't call it physical therapy, because she isn't a veterinarian, and the term is usually reserved for humans in California. Instead, she likes to call it "warm water aquatics" or "assisted swimming." "The difference is like going to the physical therapist versus going to a yoga class or getting a great massage at a spa," she says. "Both are a good workout and therapeutic, but in different ways."

Wearing a turquoise swimsuit and black swimming shorts, Chen-Rennie carries Vaastu into the seven-by-seven-foot hot tub that's set under the wooden deck in her backyard in the Sunset district. The water is warm, and wisps of steam rise off the surface. Chen-Rennie gently supports Vaastu, her blue merle-coated Shetland sheepdog, with her arms under his body, and slowly dips him into the water on the first step. As she strokes his back, she begins utilizing another therapeutic technique unique to The Rex Center--Reiki.

Reiki (pronounced 'ray-key'), which roughly translates into "universal life energy," is a healing practice that originated in Japan, according to the National Center of Complementary and Alternative Medicine, and is used by people to promote overall health and well-being.

When using Reiki, Chen-Rennie channels energy toward the dog with the intention of healing, or whatever the dog wants to use it for, including emotional healing. She says that if a dog feels the energy is too intense, it will move away, and this is how an animal chooses to accept the amount of Reiki they feel that they want, or are comfortable with. And according to Hali Chambers, a Reiki master teacher and massage therapist based in Virginia, animals will tell you what part of their body they want Reiki'ed. "Reiki is very soothing and calming," Chambers says. "It's wonderful by itself or as a compliment to other therapies."

Chen-Rennie mostly uses Reiki as part of a dog's massage session to help it relax. "A dog might come in and be really, really hyper, and not really ready for a massage," she says. However, on rare occasions, the Reiki session will trigger a phenomenon dubbed "the Reiki response," where the animal will not only relax, but also fall asleep.

The utilization of swimming as a rehabilitation tool is beneficial in encouraging dogs to move around and use muscles and limbs after an injury. "You use different muscles just to stand in water," Chen-Rennie says, wearing a blue shirt with the center's "paw drop" logo--a water droplet made to look like a paw--as she sits on the blue-and-white speckled topmost step in the empty fiberglass swimming spa. Only weighing 10 percent of their actual weight when in water, dogs that are overweight, elderly, or physically challenged find it easier to get a rigorous workout that is taxing on their body. "It's great for any dog that is recovering from surgery or muscle weakness since it puts less pressure on the joint, compared to walking or running on a surface," says veterinarian Kari DeLeeuw of Coastal Holistic, a holistic practice in Pacifica. w

Now toting the titles of professional dog trainer, warm-water therapy graduate, and certified canine massage therapist, Chen-Rennie began her journey from the world of technology into the one of wagging tails and wet noses when Vaastu needed hip surgery. She found out about warm-water therapy and canine rehabilitation after doing some research. "I decided to buy a hot tub to try swimming with Vaastu myself, and simultaneously took him to a rehabilitation center, Scout's House, in Menlo Park," says Chen-Rennie.

After talking with Cindy Horsfall, who founded the Association of Canine Water Therapy in 2005 and offers a training program at the La Paw Spa in Washington, Chen-Rennie decided to take some classes. "Providence had it that I was able to get into one of her classes last minute," she says. "My original intention was to take a class just for me and Vaastu, but I took the class, I decided that we really needed one of these warm-water centers in the Bay Area."

After introducing Vaastu to the water, Chen-Rennie slowly moves him to one end of the spa, encouraging him to swim to the opposite side. She then presses a button to turn on the jets, creating a current for the Sheltie to swim against. "They use their back legs more when they swim against a current," she says, keeping watch over Vaastu as he paddles across seven feet of water.

The Rex Center also plans on offering aromatherapy for dogs, and since dogs have a strong sense of smell, this has to be done a bit differently than for humans. Chen-Rennie first lets the dog sniff an essential oil, letting the dog self-treat by either rejecting the smell or by showing interest. If the dog licks its lips or goes after the scent, Chen-Rennie proceeds to put one or two drops of diluted oil on her palm before putting it on the animal's back, the back of the neck, and the tops of the paws.

Chen-Rennie not only wants to create a relaxing experience for pooches, but for their owners as well. Says Chen-Rennie, "My final vision is you come in, get a cup of tea, and relax."