Explore the science behind contrast therapy, the benefits of cold water immersion after sauna, and tips for safely incorporating cold plunges into your routine.
The practice of following a hot sauna with cold water immersion—known as contrast therapy—has been a cornerstone of Nordic bathing culture for centuries. Today, this ancient practice is gaining popularity worldwide as people discover its remarkable benefits. Here's everything you need to know about cold plunges after sauna.
Contrast therapy involves alternating between hot and cold temperatures, typically by moving from a sauna (80-100°C) into cold water (5-15°C). This dramatic temperature change creates powerful physiological responses in your body.
A typical contrast session might look like:
10-15 minutes in the sauna
1-3 minutes in cold water (plunge pool, cold shower, or natural water)
5-10 minutes rest at room temperature
Repeat 2-3 times
End with a final cool-down and rest period
When you enter cold water after a sauna, your body undergoes several dramatic changes:
The heat from the sauna causes blood vessels to dilate (vasodilation). Cold water causes rapid constriction (vasoconstriction). This 'vascular gymnastics' is believed to improve circulatory health and blood vessel elasticity.
Cold exposure triggers the release of several beneficial hormones:
Norepinephrine: Increases by 200-300%, improving mood, focus, and energy
Dopamine: Can increase by up to 250%, creating feelings of wellbeing
Endorphins: Natural painkillers that contribute to the 'post-plunge high'
Cold exposure activates brown adipose tissue (brown fat), which burns calories to generate heat. Over time, regular cold exposure may improve metabolic health.
The contrast between hot and cold accelerates recovery from exercise by:
Reducing muscle soreness and inflammation
Flushing metabolic waste products
Improving blood flow to damaged tissues
Decreasing delayed onset muscle soreness (DOMS)
Regularly exposing yourself to cold water builds mental toughness. The practice of voluntarily entering uncomfortable cold water trains your ability to stay calm under stress and improves stress tolerance overall.
The dramatic increase in norepinephrine and dopamine creates a natural mood boost that many describe as feeling 'alive' and energised. This effect can last for hours after your session.
Studies suggest that regular contrast therapy may strengthen the immune system. One study found that people who took regular cold showers had 29% fewer sick days.
While the cold plunge initially energises you, the overall contrast therapy session promotes deeper, more restorative sleep when done earlier in the day or evening.
If you're new to cold plunging, start gradually:
Begin with just 15-30 seconds of cold exposure
Start with cool water (15-20°C) before progressing to colder
A cold shower is a good way to build tolerance before trying a plunge pool
Focus on your breathing—slow, controlled breaths help manage the shock
Gradually increase duration as you become comfortable
Follow these rules for safe cold plunging:
Never cold plunge alone—always have someone nearby
Avoid if you have heart conditions or uncontrolled blood pressure
Don't submerge your head on your first attempts
Exit immediately if you feel numbness, extreme discomfort, or confusion
Warm up gradually afterwards—don't jump straight back into the sauna
Stay hydrated throughout your session
Avoid alcohol before or during contrast therapy
Proper breathing makes cold immersion much more manageable:
Take a few deep breaths before entering
Exhale as you enter the cold water
Focus on slow, controlled breathing once submerged
Avoid hyperventilating or holding your breath
The initial shock passes within 30-60 seconds—keep breathing steadily
Different ways to get your cold exposure:
Plunge pools: Purpose-built cold pools at spas and wellness centres
Cold showers: The most accessible option for home use
Natural water: Lakes, rivers, or the sea (in appropriate conditions)
Ice baths: Can be done at home with a large container and ice
Cold tubs: Dedicated cold water tubs with cooling systems
Cold plunges are not suitable for everyone. Avoid if you have:
Cardiovascular disease or heart conditions
Uncontrolled high blood pressure
Raynaud's disease
Cold urticaria (allergy to cold)
Open wounds
Pregnancy (consult your healthcare provider)
In Finland, where sauna culture is deeply ingrained, contrast therapy is a way of life. Finns often roll in snow, jump into frozen lakes, or use cold outdoor showers between sauna rounds. This tradition, known as 'avanto' (ice swimming), is believed to contribute to the remarkable health and longevity of the Finnish population.
The Finns say that the sauna is for cleansing the body, but the cold plunge is for cleansing the spirit.
If you're curious about adding cold plunges to your sauna routine, start slowly and build up over time. Many UK spas and wellness centres now offer plunge pools alongside their saunas, making it easy to try contrast therapy in a supervised setting.
The discomfort of cold water is temporary, but the benefits—improved mood, better recovery, enhanced resilience—can last long after you've towelled off. Give it a try, and you might just discover why this ancient practice is experiencing a modern renaissance.
Enjoyed this article? Share it with others!