Using Deliberate Cold Exposure for Health and Performance

If you are using deliberate cold exposure, the environment that you place yourself into should place your mind into a state of 'Whoa, I would really like to get out of this environment, but I can stay in safely.'

To achieve the greatest increases in metabolism through deliberate cold exposure, you want to force yourself to reheat on your own after the deliberate cold exposure, meaning you wouldn't want to go from the cold shower to a hot shower or from the cold shower to a sauna...

Cold water immersion up to the neck with your feet and hands submerged also is going to be the most effective. Second-best would be cold shower. Third-best would be to go outside with a minimum amount of clothing... that would allow you to experience cold to the point where you would almost want to shiver or start shivering.

Deliberate cold exposure, done properly, will increase your core body temperature and make you feel more alert. So, if you're doing it early in the day, that's probably terrific ... However, if you do it too late in the day, evening or night, it can disrupt sleep by way of disrupting your core body temperature.

If you are going to sit down to do some work that requires focus and working memory and cognitive attention and especially if it's some visual spatial control, meaning you have to search for things on a page, you have to organize things on a page—so this will be writing, arithmetic, basically cognitive work of any kind—15 minutes of moderate exercise done prior to that work bout could be very beneficial for you.

The heat transfer from your body into water is much higher (4x greater, if not even greater), depending on the temperature of the water, in water as opposed to in air. So, it's going to be much more efficient to do cold water immersion than anything else, cold showers after that, and put yourself into a cold environment would be the third best thing.

Deliberate cold exposure is an opportunity to deliberately stress our body, and yet, because it's deliberate and because we can take certain steps... we can learn to maintain mental clarity; we can learn to maintain calm while our body is in a state of stress—and that can be immensely useful when encountering stressors in other parts of life.

Everyone experiences a shortening of breath when they get into uncomfortably cold water ... Everyone also experiences a 30-80% decrease in cognitive function, in particular of the prefrontal cortex; the metabolism of your frontal cortex goes down; the metabolism, meaning the activity of brain areas associated with stress and panic, goes way up. And so, anchoring your mind in cognitive activities as you get into the cold can be very, very helpful for maintaining clarity of mind.

Another very common question is how often to do deliberate cold exposure. It's tough to make a recommendation on that based on any peer-reviewed study, although there are a few in humans that point to a threshold of 11 minutes total per week. So, that's total throughout the week divided into 2 or 4 sessions of 2 or 3 minutes or so.

If your main goal is hypertrophy and strength, it is probably best to avoid cold water immersion and ice bath immersion in the four hours immediately following that strength and/or hypertrophy training.

When you get into cold water, and you remain there for some period of time, your body is generating heat, and that heat generates what's called a thermal layer that surrounds your entire body. So, if you stay still, you are actually warmer than if you move around.

Approximately 2 hours before the time you wake up is your so-called temperature minimum. So, your temperature minimum is a time within the 24-hour cycle when your body temperature is at its lowest.