From plunging into freezing cold ice baths to squeezing into compression socks, commercial methods to relax our muscles and minds have never been more abundant. Amidst these options, however, lies one that has piqued the interest of many scientists and consumers: sensory deprivation tanks. Otherwise known as “restricted environmental stimulation technique,” or REST, these pod–like devices require users to lie nude in a ten-inch-high pool filled with Epsom salt and water, heated to match internal body temperature. With all lights off and earplugs in, one can silently float and disconnect from external stimuli.
Removing the ability to see, hear, and touch as well as detaching oneself from a busy environment has immense health benefits. Patients generally report reduced anxiety, muscle relaxation, improved mood and creativity, deeper sleep, and even personal growth after just one hour. Though currently perceived as a luxury health fad for many stars, athletes, and businessmen, the proven benefits of float tanks have profound clinical importance for all but the claustrophobic.
As counterintuitive as it may seem, switching key senses “off” can help reconnect you with your body and mind. Far from being a microtrend, REST has been the subject of numerous studies since its invention. The World War 2 neuroscientist who conceptualized these pods, John C. Lilly, originally thought this isolation could be a method to explore the limits of human consciousness. Results aside, after years of research and a few celebrity endorsements, the tank became a phenomenon.
One of the most significant benefits seen after regular use of sensory deprivation tanks is the reduction of stress and anxiety. The concept of floating in silence and darkness might seem daunting, but it creates an environment where the mind can achieve deep relaxation and “reset.”
Another primary benefit of these tanks is their ability to facilitate brain waves from a beta state (associated with active thinking and alertness) to a theta state (which is linked to deep relaxation and meditation). This shift is critical as beta brain waves are dominant during engaging, attentive, or anxious thinking, while theta brain waves are prevalent in states of deeper relaxation, creativity, and REM sleep. During a flotation session, the reduction of external stimuli allows the brain to transition into the theta state more easily.
Concurrently, the buoyancy provided by the Epsom salt solution allows the body to float effortlessly, relieving pressure on joints and muscles. Specifically, the magnesium in Epsom salt is absorbed through the skin, helping to reduce inflammation, which can be beneficial for athletes or individuals with chronic pain conditions.
This state of deep relaxation achieved by changing brain waves and salt absorption is also associated with reduced production of cortisol, which normally spikes during periods of stress and anxiety. Cortisol, a major hormone produced by the adrenal glands, follows a diurnal rhythm, peaking in the morning and declining throughout the day. However, chronic stress can disrupt this rhythm, leading to consistently high cortisol levels that negatively impact overall health. The Epsom salt also inhibits ACTH release, the hormone that signals the adrenal glands to release cortisol. Reduced cortisol from regular flotation therapy sessions can be valuable for individuals with generalized anxiety disorder (GAD).
In a world filled with constant bustle and pressure, taking the time to tune out noise and do something as simple as float can have profound effects on both mental and physical health. The warmth of the water, combined with the weightlessness of floating, creates an environment where the muscles and mind can recover. Despite its reputation as a short-lived craze, the clinical importance of float tanks is well–supported by research. Already proven to improve anxiety and muscle soreness, REST could potentially be a supplemental treatment for an even wider array of health issues with further research. As interest in holistic health practices continues to grow, sensory deprivation tanks may become an increasingly common tool for more than Lilly could have imagined.
“The warmth of the water, combined with the weightlessness of floating, creates an environment where the muscles and mind can recover.”
