Float therapy is making a comeback, more therapeutic and enticing than ever. The basic idea is you float in a dark, enclosed capsule filled with warm super-salted water. It’s an experience that fans claim relaxes both body and mind, reduces chronic pain and promotes better sleep. The more often you do it, the greater the benefits, they say. The folks at True REST Float Spa in Gilbert, Arizona, near Phoenix, invited me to give it a try.

Floatation therapy tanks were invented in the mid-1950s, although back then they were known rather barbarically as “isolation tanks” or “sensory deprivation tanks.” The therapy is based on an approach to deep relaxation called REST, or Restricted Environmental Stimulus Therapy. It was popular with scientists, hippies and New Age followers but died out in the 1980s as the fear of AIDS spread.

True REST Float Spa is a modern, immaculate day spa with private treatment rooms appointed with showers, thick towels and toiletries. You’ll step inside a giant white clamshell of a tub, then close the lid and lie back. (They call it a pod, and it contains 1,000 pounds of dissolved Epsom salts.) You will float on the surface with no effort on your part. The anti-gravity nature of the experience removes all pressure from your spine and joints, and the body-temperature bath creates the sensation you and the water are one.

Try not to splash, or you could get salt in your eyes. Just in case, a spray bottle of fresh water and a towel are within reach. (PAM’S TIP: Avoid shaving before a float—your skin will be more sensitive, and the salt will sting.)

A few minutes into my one-hour session, the lights and music were programmed to shut off. I was left in a silent blackout, and my thoughts wandered on their own. They focused on nothing in particular, just the feelings of weightlessness and harmony with the universe. Some people report “seeing” colorful patterns or geometric shapes, but I didn’t.

Claustrophobics can leave the lights on, but the whole point is to cut out the environmental clutter, so the mind can be quieted. And if you leave the pod open, the warm air escapes, and you’ll get cold.

I was apprehensive going into the pod, but soon gave in to the embrace of the water and the solitude of the cocoon. All too quickly, the music and light returned, signaling my time was up. After a quick shower came yet another delight: A stop at the Oxygen Bar to breathe a choice of scented inhalations including vanilla, lemongrass and lavender. My skin was silky, my mind was clear and I was invigorated to get on with the day. Yes, I would do it again.

True REST Float Spas are expanding around the country. Look for one in your area.