Cold Plunges and Deliberate Cooling

The benefits of cold plunges arise from intentionally activating your nervous system’s stress response in nonharmful ways. This short-term stress response significantly increases the levels of endorphins (natural “feel-good” chemicals) and catecholamines including dopamine and norepinephrine,  perhaps boosting mood, enhancing focus and improving mental acuity for up to several hours after cold exposure, even if it only lasted for a few minutes.

One of the key benefits of regular cold exposure (about 11 minutes total throughout the week) is its effects on metabolism: cold exposure causes shivering, which activates norepinephrine release directly into fat cells. This facilitates the conversion of white fat into brown fat, which has higher mitochondrial density and thus burns more calories than white fat. Over time, cold exposure can also help regulate cortisol levels and lead to lower resting heart rate, blood pressure and possibly improved overall cardiovascular health.

Additionally, cold exposure has mental health benefits, serving as a tool to build resilience through controlled exposure to stress. Cold therapy practices allow individuals to learn to remain calm and mentally clear in stressful situations, a skill which can be applied when facing unexpected personal or work-related stressors in daily life. Managing stress is one of the cornerstones of mental health and well-being, making cold exposure a powerful protocol to incorporate into your routine to buffer stress.

To safely practice cold exposure, it’s important to follow several guidelines in order to maximize potential benefits while minimizing risks. Cold water exposure protocols involve the parameters of temperature, duration and frequency. If you are new to cold exposure, don’t start with extreme cold — instead, gradually work up to colder environments. The water should be cold enough that you are uncomfortable and want to get out, but it is still safe to remain in for one to three minutes. Prioritize safety by having someone present if you are inexperienced or are going into particularly cold or icy water.

Generally, a water temperature of 55-60° F, or 12.77-15.55° C, is a good starting point for beginners. More experienced individuals might opt for temperatures down to the low 40s, always ensuring it’s done with caution. Avoid breathwork (such as cyclic hyperventilation) before entering cold environments, as this can alter your natural gasp reflex, which is crucial for maintaining safety in cold water. During cold exposure, use deep, controlled inhales and extended exhales to help maintain calmness.

The most effective type of cold exposure is cold water immersion that submerges the body up to the neck, including feet and hands. This method is the most effective at stimulating a healthy stress response in your nervous system and is the most common method of cold exposure used in scientific research. Although cold showers are not as effective as cold baths, they are still beneficial for those who do not have access to a cold plunge tub.

Body temperature can significantly impact athletic performance and recovery. “Warming up” at the start of a workout can enhance performance and reduce risk of injury. However, if core body temperature climbs too high, it can disrupt the cellular mechanisms of muscle contraction and trigger the nervous system to amplify perceived effort — making exercises feel harder — and therefore reduce endurance to avoid further overheating.

Muscles require a specific temperature range to function optimally, and excessive heat can halt muscle contractions, reducing endurance and performance. Stanford professor and expert in temperature regulation, Dr. Craig Heller, discussed how a brief cold shower or bath before aerobic activity can increase dopamine and adrenaline and release excess heat, thereby delaying the onset of sweating and allowing for improved performance in endurance sports. However, avoid cold exposure immediately after strength and hypertrophy training to prevent interference with muscle growth adaptations.

Cooling glabrous skin surfaces (such as the palms, face or soles of the feet) during a strenuous workout can lower the body’s core temperature to reduce overheating and help increase endurance and strength capabilities. Even passing a cold object, such as a frozen soda can, between the hands can help reduce overall body temperature without the need for advanced equipment. Palmar cooling (cooling the palms of your hands or feet) can also decrease delayed onset muscle soreness (DOMS), enabling quicker recovery.