It was 1980 when the film Altered States floated into cinemas and catapulted William Hurt into the spotlight. The flick did more than make Hurt famous. It made people aware of flotation tanks.

"I'm going to float in that?" is the likely reaction of first-time floaters to the 8x4x4 foot tank.

Floatation tanks are completely enclosed containers, in which a person floats effortlessly in a high-density saline solution. With no light, sound or other distractions, the mind and body enjoy a uniquely rejuvenating experience.

The enclosure contains just 10 inches of water and an incredible 800 pounds of Epsom salt (to keep you buoyant) so you rest without gravity impacting your body. The water is heated to your external skin temperature of 95.0 degrees Fahrenheit. You can not distinguish between yourself and the water and the air.

Scientists estimate that our brain "wastes" about 90% of its energy every day on sifting and filtering out a barrage of "junk" information and external sensory input. So the fact that you're not able to see or hear anything in the tank is significant. In this environment of minimal external stimulation, a floater's mind will often enter a dreamlike state in which some recall vivid memories, have sudden insights or bursts of creativity. With the mind most receptive to suggestions in this state, many people listen to hypnotic or foreign-language taps while floating. Floating isn't just about freeing the mind; for some, the tank frees the body from tension and offers relief from injuries. As floating can soothe the muscle damage by releasing lactic acid buildup, many athletes float after achieving the "burn" at he gym. People also float to seek relief from carpel tunnel syndrome, arthritis and fibromyalgia, says Lynette Anderson of the Floatation Center in San Francisco. "It allows the muscles to open up because lactic acid is removed; it allows blood to get circulated into areas that would otherwise be restricted. And blood carries oxygen. And oxygen is healing."

As you float, your organs are also resting. The organs are suspended in a way Anderson likens to a piece of fruit in a Jell-O mold. There's no tension anywhere, so your organs including your heart, don't have to work as hard.

Studies have shown that while floating in the float tank you can more easily reach the Theta brain waive zone...that semiconscious state that you experience in the process of falling asleep or waking up. This is the zone that zen meditation masters are able to reach he Theta brain wave zone...that semiconscious state that you experience in the process of falling asleep or waking up. This is the zone that Zen meditation masters are able to reach and stabilize in only after many years of intense training, and inexperienced floaters reach it without any training at all. This deep state of relaxation can be even more beneficial than sleep. In this relaxed state your body can attend to nurturing and repairing, by lowering your muscle tension, blood pressure, heart rate and oxygen consumption. It can strengthen your immune system, alleviate pain and speed healing. Stress hormones and chemicals such as adrenaline, and cortisol are removed from your blood stream and are replaced by endorphins.

What is nice is that all of these biological and biochemical changes occur on their own as natural response to your super relaxed mind and body, with not raining or prior knowledge required whatsoever. Benefits from multiple floats are cumulative because your mind and body learn how to relax even deeper with every float.