Are cold plunges worthwhile?
Musicians like Drake and Harry Styles, and athletes like Georges Saint-Pierre swear by them. Wim Hof, nicknamed the Iceman, has made them the cornerstone of his powerful wellness method.
Ice plunges are all the rage on TikTok today, but cold plunges are nothing new. Cold therapy has been practiced for centuries, much like Nordic baths, which alternate between hot and cold and, most recently, cryotherapy, which athletes use to manage muscle recovery.
What is a cold plunge?
The idea is to immerse your body in cold water ranging from 10oC to 15oC.
Some will even go so far as to fill the bath with ice too.
Cold plunges are often done after a workout and last between three and five minutes.
How the body reacts to extreme cold
To conserve heat, blood vessels constrict. This is known as vasoconstriction. This reduces blood flow to the limbs, directing it instead to vital organs such as the brain, heart, kidneys and liver. Numbness may occur in the extremities and an analgesic, anti-inflammatory effect may be felt.
A temporary rise in blood pressure is also observed—breathing accelerates, as does heart rate. This phenomenon is also experienced when alternating between hot and cold baths.
To maintain a constant internal temperature in freezing water, shivering thermogenesis may occur, which is a mechanism that increases heat production through shivering.
In some cases, cold-induced muscle cramps and an increase in cortisol (the stress hormone) and endorphin (the happy hormone) levels are observed.
Everyone reacts differently to the cold—some will refer to themselves as polar bears, while others not so much. There are several factors in play here:
- age
- sex
- body fat
- body surface area
What are the purported benefits of ice plunges?
Enthusiasts are eager to praise the many virtues of ice plunges:
- Immune system boost
- Weight loss due to brown fat activation
- Faster post-exercise recovery
- Mood enhancement
- Better stress management
- Heightened concentration
- More restful sleep
Too good to be true? Hmm.
Does it really work?
Without wanting to burst anyone’s bubble, none of the virtues above have been backed by scientific research. If anything, results can be somewhat biased because participants tend to be high-performance athletes in peak physical shape, not the average person.
More controlled research will have to be conducted on the benefits of ice plunges before any significant conclusions can be drawn.
Here’s what science has to say about the benefits of ice plunges:
- Reduced inflammation and muscle pain
- Rapid temperature reduction can treat intense heatstroke, especially in marathon runners
- Stimulation
The risks of ice plunges
Ice plunges pose a number of health risks. Exposure to intense cold can cause:
- Frostbite and cold burns
- Hypothermia
- Hyperventilation, which can cause dizziness and loss of consciousness
In actuality, the repeated exposure to extreme cold can damage nerve endings and tissues, which can make the body even more sensitive to cold.
Beware of ice plunges if...
According to the American Heart Association, cold plunges can cause sudden changes in respiration, heart rate and blood pressure, which can be dangerous for people with heart disease, high blood pressure or at risk of a stroke.
Cold plunges are not for people who suffer from:
- Arrhythmia
- Type 1 or 2 diabetes
- Neuropathy
- Poor blood circulation
- Venous stasis
- Cold agglutinin disease
Pregnant women, children and those seeking a quick fix to the pain of an untreated injury should also avoid cold plunges.
Before plunging
Before taking part in the cold plunge craze, talk to your healthcare professional. Find out about the risks to your health and what precautions to take.
If you get the green light, start slow. Start with immersions of one to two minutes, then increase the duration as your body adapts. Your sessions should never last longer than five minutes though.
Apply the same principle to temperature. Start at 20oC. Cool the water as you go. Remember, temperatures below 15oC increase the risk of thermal shock, arrhythmia and high blood pressure.
To offset the effects of hypothermia, sit in a sauna for 15 to 30 minutes. Breathing exercises can also help you tame the cold.
What equipment is required?
A bath or tub is ideal for plunging into icy water.
Adding ice cubes is a good way to cool the water, although some enjoy frolicking in the snow.
Hand and foot protection is essential. Wear neoprene gloves and socks that are at least 5 mm thick.