flotation therapy
If you've ever considered flotation therapy, you're not alone. In fact, this sensory deprivation technique is becoming more popular, and has benefits ranging from simple relaxation to recovery after a traumatic brain injury.

Most flotation tubs or tanks are about the size of a queen-sized bed and contain no more than 1 foot of water that has been supersaturated with 850 to 1,000 pounds of Epsom salt to 200 gallons of water.

According to Graham Talley, founder of Float On, which hosts an annual Float Conference, this makes the water "more buoyant than the Dead Sea."1 The water is heated to 93.5 degrees F., which is a normal skin surface temperature. Writing for Men's Health, Deanna Debara describes her experience:2
"Float devotees include celebrities like Steph Curry and Joe Rogan, who have promoted it as a post-workout recovery tool and a way to reduce muscle soreness.
Floating devotees claim that the therapy can be a cure-all for everything from hypertension to insomnia, but I was interested in trying it for one reason: to relax ... If there was anything out there that could help me loosen up and just chill, I was game ...
During the first few minutes of the float, I panicked ... It took everything in me not to feel around in the darkness to find the light ... But the longer I stayed in the tank, the more things started to slow down. My shoulders loosened up. My breathing deepened. My thoughts stopped racing ...
As time went on, I moved past relaxation and entered what I can only describe as an almost trance-like state; at times, I couldn't tell where my body ended and where the water began. I couldn't tell if my eyes were opened or closed, and I couldn't tell if I was awake or asleep. It was like meditating on steroids."
Health Benefits of Flotation Therapy

As noted in the video above, flotation therapy has been linked to an array of beneficial effects, including:3,4
  • Stress reduction 5
  • Reduced anxiety,6 depression and symptoms of post-traumatic stress by inhibiting cortisol production 7,8,9 and inhibiting the fight or flight response in your amygdala
  • Pain relief 10
  • Increased creativity 11
  • Deepened meditative state
  • Reduced inflammation
  • Addiction relief
  • Improved sleep
  • Mood enhancement 12
  • Athletic performance enhancement by speeding up the elimination of lactic acid
  • Improvements in chronic fatigue and symptoms associated with burnout 13
According to a 2014 study,14 sensory deprivation treatment in a flotation tank "has beneficial effects on relatively healthy participants" and could have value as preventive health care by lowering depression and anxiety. According to the authors:

"Stress, depression, anxiety, and worst pain were significantly decreased whereas optimism and sleep quality significantly increased for the flotation-REST [restricted environmental stimulation therapy] group. No significant results for the control group were seen. There was also a significant correlation between mindfulness in daily life and degree of altered states of consciousness during the relaxation in the flotation tank.

The Benefits of Silence

While it's difficult to tease out exactly what it is about flotation therapy that causes these effects, silence alone is known to have very similar benefits. According to Psych Central, spending time in complete silence has been shown to produce physiological changes, including:15 Silence also promotes emotional and psychological benefits, such as:
  • Increased creativity
  • Self-awareness and gratitude
  • Self-observation and self-reflection that leads to self-improvement
  • Spiritual connection
  • Improved sleep
Clearly, it doesn't get a lot quieter than floating in a sensory deprivation tank for an hour. Another option might be to join a silent retreat, where you spend anywhere from a couple to 10 days in complete silence.16

Flotation Therapy in the Treatment of Brain Injuries

Flotation therapy can also be enormously beneficial in the treatment of traumatic brain injuries (TBIs). Dr. Dan Engle, who is board-certified in adult psychology and neurology, discusses this and other techniques in his book, "The Concussion Repair Manual: A Practical Guide to Recovering From Traumatic Brain Injuries." According to Engle, whom I've interviewed on this topic:
"Flotation therapy is on the front line of many different recovery and regenerative medicine protocols, because it has the opportunity to reset so many different systems.
When somebody drops into a float tank ... it's essentially the first time since they were conceived that they're without environmental stimuli ... There's no gravity; there's no appropriate [sensory] reception ... Everything is offline, so to speak.
Eighty percent of what the brain is consistently bringing in is environmental stimuli. Now, there's more energy toward the recuperative mechanisms.
It's both a brain technology and a consciousness technology, because ... [the] flotation tank [experience] is like meditation on steroids. If somebody's using [for] recuperative and regenerative [purposes], they may well find more peace in their lives outside of the tank as well ... because it starts to reset the neuroendocrine system.
Cortisol levels normalize. Global inflammatory markers normalize. Blood pressure normalizes. The relationship between the brain and the endocrine or the hormonal systems starts to optimize ..."
For those recuperating from a TBI, Engle recommends doing a series of eight to 10 floating sessions within a three- to four-week period. By the end of that series, you should notice significant improvement in your symptoms. You may also find yourself more at ease in general, sensing a better "flow" in your life. For maintenance, do one or two sessions per month.

Flotation Therapy for Stress-Related Muscle Pain

Speaking of dosage, a study17 designed to evaluate the effectiveness of 12 versus 33 sessions for stress-related ailments such as muscle pain and tension found that, from a subjective perspective, maximum results were obtained after 12 sessions. In fact, no additional improvements were found after 33 sessions. According to the authors:
"A similar pattern was observed concerning the stress-related psychological variables: experienced stress, anxiety, depression, negative affectivity, dispositional optimism and sleep quality.
For blood pressure, no effects were observed after 12 sessions, but there was a significant lower level for diastolic blood pressure after 33 sessions. The present study highlighted the importance of finding suitable complementary treatments in order to make further progress after the initial 12 sessions."
Altered States of Consciousness May Impact Pain and Stress Thresholds

Aside from the effects of silence and the regenerative effects of resetting the neuroendocrine system, flotation therapy18 also appears to impact your physiology through the induction of an altered state of consciousness. A study19 investigating this aspect was published in 2004.

Twenty-three athletes underwent two sensory deprivation sessions, one in a flotation tank and the other in a sensory deprivation chamber. In the latter, you simply lie on a bed in a soundproof, completely darkened room. Immediately following each of the sessions, the participants' pain threshold was measured by inflating a blood pressure cuff on one arm.

The degree of altered states of consciousness of each participant was also measured using an instrument capable of "assessing experienced deviation from normal state." As one might suspect, participants experienced far greater alterations in consciousness in the flotation tank than in the dark, soundproof chamber.

Curiously enough, higher alterations in consciousness were found to correlate with higher levels of experienced pain and stress. According to the authors:
"These results suggest that the particular distinguishing features of flotation-REST and chamber-REST may cause selective deviations from normal levels of consciousness ... that may underlie the subjective experience of pain and stress thresholds."
A later study20 found that people who are more emotionally sensitive and more prone to anxiety and self-absorption were significantly more likely to experience altered states of consciousness or so-called mystical states during flotation therapy than less sensitive individuals.

Meditative States Protect and Improve Health

Overall, meditation has been shown to have significant health benefits, so it's not so surprising that flotation therapy would have similar effects. Many of these benefits could be said to be a byproduct of stress reduction. Stress is a well-recognized culprit that can promote ill health across the board, and the ability of meditation to quell stress is an important health benefit.

Researchers at Carnegie Mellon University published a study in 2015 claiming they'd found the biological mechanism by which mindfulness affects physical health. In a nutshell, meditation impacts your biology and physical health via "stress reduction pathways" in your brain. As explained in the press release:21
"When an individual experiences stress, activity in the prefrontal cortex - responsible for conscious thinking and planning - decreases, while activity in the amygdala, hypothalamus and anterior cingulate cortex - regions that quickly activate the body's stress response - increases.
Studies have suggested that mindfulness reverses these patterns during stress; it increases prefrontal activity, which can regulate and turn down the biological stress response.
Excessive activation of the biological stress response increases the risk of diseases impacted by stress (like depression, HIV and heart disease). By reducing individuals' experiences of stress, mindfulness may help regulate the physical stress response and ultimately reduce the risk and severity of stress-related diseases."
Such effects may explain why meditation can help to relieve stress-related diseases such as:
  • High blood pressure
  • Chronic pain, including headaches
  • Respiratory problems such as emphysema and asthma
  • Sleep disturbances and fatigue
  • Gastrointestinal distress and irritable bowel syndrome
  • Skin disorders
  • Mild depression and premenstrual syndrome (PMS)
Meditation can also have a distinct impact on gene expression. For example, researchers at the Benson-Henry Institute for Mind Body Medicine22 have sought to quantify the benefits of the relaxation response by assessing gene expression before and after meditation, and have compared effects of short- and long-term meditation routines.

Among their findings, they discovered that meditation has anti-inflammatory effects. In one study,23 participants who participated in an eight-week meditation program, as well as longer-term meditators, saw increases in antioxidant production, telomerase activity and oxidative stress.

One theory is that NF-kappa B genes may act as messengers between psychological and physical stress, thereby causing your body to translate worry into inflammation. What's more, there appears to be a dose-dependent relationship at play, so the greater the relaxation response, the greater the optimization of genes and the greater the anti-inflammatory effects.

Flotation therapy induces tremendous physical and mental relaxation, allowing for the experience of basically being bodiless, and this deep relaxation may well be part and parcel of how it reduces anxiety, pain and inflammation.

Magnesium Augmentation

Perhaps one of the least appreciated aspects of floatation tanks is that it likely increases your magnesium levels, and since over 80 percent of the public is deficient in magnesium, this is a great side benefit since you are floating in a half-ton of Epsom salt.

In fact, this aspect of float tanks has intrigued me enough to consider getting one, as I, like many people, have a hard time getting my magnesium levels high enough. It's a major challenge to increase magnesium by oral supplementation without causing loose stools.

If anyone has been using a float tank and performed pre- and post-RBC magnesium levels, please leave your experience in the comments below as it is difficult to find documentation on this aspect of flotation therapy.

Sources and references here.