A cold plunge is when you fully submerge your body up to your neck in water below 59° Fahrenheit (15° Celsius).

59° Fahrenheit—two to four sessions per week for eleven minutes total time—is enough to cause measurable metabolic boost according to Dr. Susanna Soeberg.

Dr. Susanna Soeberg Research

Her study on cold plunging was performed on winter streamers. This means flowing water that breaks the thermal barrier. This is different from cold plunging in still water (horse troughs or barrels filled with ice) or low float rate cold plunges / ice baths / cold baths.

Another frame of reference to consider: you ought to cold plunge at a temperature where it is uncomfortably cold yet safe. This is a great rule of thumb created by Dr. Andrew Huberman.

You have a unique cold tolerance. Do not see cold exposure as a competition, but rather as a means to build insight, resilience, and experience cascading health benefits.

Some people naturally have high tolerances; others naturally have low tolerances.

If you are just starting out, start at a higher temperature and lower duration. Stairstep your progress and determine your sweat spot over time. Once you understand your thresholds / limits, you can begin exploring different temperatures and times to increase your adaption during a cold plunge.

Cold plunging up to the neck, fully submersed in water, provides
a significantly higher dose of cold exposure that cold showers.

If you have the opportunity to cold plunge, see for yourself
the difference between submerging to your chin vs. to your shoulders. In
addition, explore the difference between having your arms in the water and
outside the water.

You will notice an increase in intensity from having your
neck and arms submerged.

Furthermore, you can experiment full dunking your head
underwater at the start and at the end of your cold plunge. This leads to
further adaptation / adjustments your body goes through during cold exposure.

Cold plunging is nothing new—cultures around the world have leveraged cold exposure for thousands of years as part of ceremonies / protocols
for renewal. What has been missing is peer reviewed science highlighting the
enormous, multi-faceted benefits that cold plunging provides.

Below is a list of health benefits that research is beginning
to uncover. In addition, Youtube Videos / Articles that are highly educational
on cold plunging / cold exposure.

• Boost Your Immune System
• Improve Cardiovascular Health
• Mitigate Alzheimer's and Dementia
• Increase Testosterone
• Alleviate Arthritis
• Stabilize blood sugar (increase insulin sensitivity)
• Blast Through Anxiety
• Address Mental Health
• Contributes to Longevity
• Speed Recovery Times
• Reduce Inflammation
• Eliminate Depression
• Leverage feel good hormones
• Makes skin and hair look radiant

 * Disclaimer: These claims are not approved by the FDA. You
are responsible for your own research.

Cold Plunging Resources and References that go
into depth on the subject:

Dr. Andrew Huberman on Cold Exposure

Huberman Podcast on Cold Plunging

Dr. Rhonda Patrick on Cold Stress

Dr. Rhonda Patrick References

Once you have gained insight into your tolerance, varying temperatures and duration is incredibly useful in keeping your body always guessing.

Think of changing temperature and duration as similar to changing weights, sets, and reps while working out. The goal is to keep your body always guessing, always adapting, in order to maximize the benefits.

When Dr. Susanna Soeberg is asked what temperature and duration is best, her response is “The perfect temperature is simply to keep changing it.”

Exercise, cold exposure (cold plunge), heat exposure (sauna), and intermittent fasting are all hormetic stressors. All of these protocols provide the most benefit by changing up your routine.