The use of cold water immersion in natural medicine is probably as old as mankind! 

The cold shock you get from entering an ice bath tub causes a Hormetic response that activates genetic pathways to deal with stress and recovery. Twenty seconds of cold water immersion below 5 degrees celsius, has been proven to increase the energy producing Mitochondria cells, by as much as 200%! This means that you will benefit from improvement in the muscle’s aerobic capacity, endurance, recovery times and greatly reduce muscle soreness.

What Happens to Your Body During Cold Immersion?

During cold water immersion, your skin’s cold receptors will sense that your skin is cooled very quickly. This will instantly cause you to gasp for air and rapid uncontrollable breathing will follow. You will also experience an increase in heart rate and blood pressure.

This 'cold shock response' is a type of Hormetic stress. Fast adaptation will follow, because your body is overcompensating in accordance with the stressors. A study on winter swimmers found that the body will produce a chemical response which stimulates a release of Noradrenaline in response to cold shock.

Naturally this chemical is released in the body during 'fight or flight' response to perceived danger. It has been proven to increase alertness and arousal, and to speed up reaction time. Norepinephrine has been shown to play a role in a person's mood and ability to concentrate.

So how is that important to recovery? According to Dr. Rhonda Patrick’s findings on the benefits of cold exposure and her presentation at Biohackers Summit on the same topic, Noradrenaline causes a spike in Mitochondrial biogenesis. 

Simply put, Mitochondria are the energy producers in our body, a signal is sent to the body to make 200-300% more Mitochondria, which results in an instant energy spike, faster recovery and even a fat burning metabolic response.

Additionally…

Taking an ice bath after physical stress (like a workout) can improve recovery by changing the way blood and other fluids flow through your body. During cold water immersion, your blood vessels constrict (close up); when you get out, they dilate (or open back up). This process helps flush away metabolic waste like lactic acid post-workout. This can reduce muscle inflammation and speed up recovery.

When and When Not to Take an Ice Bath for Muscle Recovery?

The data on this topic is mixed, so let us do our best to advise you accordingly…

After exercise your muscles can feel sore. The soreness is caused by a temporary inflammation around micro muscle tears, not by lactic acid as was once thought… When the damage heals, your muscles rebuild stronger and more conditioned to the exercise or intensity that caused them.

The effects of ice baths on exercise performance differ depending on what kind of exercise is involved.

After strength exercise, cold water immersion may in fact hinder the benefits of exercise".

Cold water immersion might be interfering with the natural protein and cellular responses that happen in the muscle after each strength session according to Llion Roberts An expert from Griffith University in Exercise Physiology, Musculoskeletal Science.

Effects on endurance training are recorded to be quite different. Christopher Mawhinney, an expert in sports science from Mahidol University in Thailand, says that cold water immersion turns on mitochondrial bio-genesis. 

Mitochondrial biogenesis is when cells increase their numbers of mitochondria, which release more energy. Mitochondrial bio-genesis is one of the positive effects that comes from endurance training, so ice baths could help to increase this benefit greatly.

The key takeaway 

Taking ice baths after endurance type training can be very useful at improving muscle stamina and recovery. But taking ice baths or other cold exposure methods straight after strength training should be avoided or carefully scheduled, because it could hinder muscle growth. 

For How Long Should You Take an Ice Bath for Muscle Recovery?

In general you should try and last as long as possible… But never push your body too far beyond its limits. As a general rule of thumb, if the water in the ice bath tub is colder than 5 degrees celsius you would need as little as 20 seconds to start experiencing benefits.

So starting from there, 20 to 30 seconds intervals of ice bathing per day would be more than enough for your first week of cold water exposure.

When the body adapts to the cold, you will be able to sit in the ice bath for longer periods of time.

Your cold water immersion can look like this:

They key is to gradually train and adapt your body, because prolonged periods of cold exposure could have serious side effects (if you are not conditioned to handle the stress):

• Hypothermia
• Nerve damage
• Pain