The Rise of Cold Plunges: Benefits, Sleep Impact & Why Everyone’s Doing It

Cold plunges can support muscle recovery and daytime alertness, but their effect on sleep is not automatically positive.

While cold exposure may reduce soreness and help you feel more awake, doing it too close to bedtime can spike alertness and delay sleep.

The real benefit comes down to timing, duration, and how your body responds to cold.

What is a Cold Plunge?

A cold plunge, sometimes called an ice bath, involves immersing your body in water below 60°F (15°C). This practice dates back centuries, rooted in traditions that valued the health benefits of alternating hot and cold exposure.

Today, cold plunges are popular among athletes and wellness enthusiasts alike, recognized for their role in recovery, energy, and overall well-being.

The Popularity Surge

Cold plunges have gone from niche recovery tool to mainstream wellness trend, thanks in part to athletes and celebrities like Harry Styles, Lady Gaga, and David Beckham. What started as a way for athletes to speed up recovery has become a go-to ritual for anyone looking to boost energy, sharpen focus, and support overall well-being.

So how did sitting in ice water become a wellness staple? Check out The History of the Ice Bath to see how this ancient practice found its way into modern recovery routines.

In a 2023 study, it showed that cold-water immersion can help reduce muscle soreness, support weight management, and even improve mood by increasing noradrenaline and dopamine levels. [1] It’s no longer just for elite athletes—cold plunges are attracting a wider audience eager to experience both the physical and mental benefits.

The Many Benefits of Cold Plunge

Ready to take the plunge? Here’s a quick breakdown of the cold plunge benefits for your body and mind:

Muscle Recovery

For athletes, cold plunges can be a powerful tool to ease post-workout soreness. The cold water causes blood vessels to constrict, which may help limit inflammation and swelling in overworked muscles. This process also helps flush out waste products, supporting quicker healing and recovery so you can get back to training sooner.

Enhanced Mood and Mental Clarity

Cold water immersion can spark the release of endorphins, often lifting mood and easing feelings of stress or anxiety. Many people describe a sense of euphoria after a plunge, along with greater mental resilience and clarity.

Regular practice has also been linked to sharper focus and improved cognitive function, making it as much a boost for the mind as it is for the body.

Stress Reduction

Cold-water immersion can act as a natural stress reliever. In a study from the University of South Australia, participants reported feeling less stressed within 12 hours of exposure. [2]

For those managing high-pressure environments or simply looking to support overall well-being, cold plunges may offer a refreshing way to reset both body and mind.

Immune System Boost

Some research suggests that regular cold exposure may help strengthen the immune system, potentially reducing the risk of illness and supporting overall health.

While the long-term effects are still being studied, early findings point to promising benefits for immune function.

Improved Sleep Quality

Cold plunges may improve sleep quality by activating the parasympathetic nervous system, promoting relaxation and deeper, more restorative sleep. [3]

A systematic review published in PLoS One found that participants experienced reduced stress levels and improved sleep outcomes after cold-water immersion. [4] However, timing is key.

Taking a cold plunge too close to bedtime can leave some people feeling too alert to fall asleep easily.

How Cold Plunge Impacts Sleep

Wondering what a cold plunge does for your sleep? Here’s a look at the possible benefits and drawbacks.

Melatonin Production

Cold exposure may stimulate melatonin. Its the hormone that helps regulate your sleep cycle. By lowering core body temperature, cold plunges can create the right conditions for better rest.

In fact, a study on swimmers who regularly practiced cold-water immersion found improvements in sleep quality, pointing to potential benefits for those dealing with sleep troubles. [5]

Activation of the Parasympathetic Nervous System

Cold plunges stimulate the parasympathetic nervous system—the part of your body that encourages relaxation and energy conservation. [6] This shift can make it easier to unwind and drift off to sleep.

The cold-water “diving reflex” further supports this process by countering the drop in parasympathetic activity that stress or intense exercise can cause, ultimately promoting deeper, higher-quality rest.

Increased Slow-Wave Sleep

Cold plunges may support slow-wave sleep—the deepest stage of rest that’s vital for muscle repair, immune health, and mental sharpness. By lowering core body temperature, cold exposure encourages relaxation and helps the body slip into this restorative phase more efficiently.

Best Times for Cold Plunging

Timing matters when it comes to cold plunges, especially for recovery and sleep. Taking the plunge right after a workout can help reduce inflammation, clear out metabolic waste, and decrease muscle soreness (so long, DOMS).

It’s no surprise that many athletes make cold exposure a regular part of their recovery playbook.

• Morning: Start your day with a cold plunge to wake up your body, sharpen focus, and give your metabolism a jump-start. It’s a quick way to boost energy and mental clarity.
• Post-Workout: After tough training, a plunge can help ease inflammation, speed recovery, and keep muscle soreness in check.
• After Sauna or Heat Therapy: Pairing hot and cold (contrast therapy) promotes circulation, supports lymphatic drainage, and enhances overall recovery.
• Before Bedtime: Take a plunge 1–2 hours before sleep—enjoy the initial energy lift, then let your body naturally settle into a calmer state, making it easier to drift off without restlessness.

Make sure you keep it brief. Cold plunges don’t need to be long to work. Just a couple of minutes is enough to lower core temperature and cue your body to relax. Even a quick two-minute dip can make a noticeable difference in how fast you fall asleep and how deeply you rest.

Potential Drawbacks: Before Bed

While cold plunges have benefits, they may not always be the best choice right before you go to bed. For some, the sudden shock of cold water can feel stressful, especially if your body isn’t used to it.

That initial jolt might cancel out the calming effect you expect afterward. Cold exposure also triggers stress hormones like cortisol, which can boost alertness and energy, making it difficult to relax and fall asleep.

Times to Avoid: It's best to avoid within 2 to 3 hours of bedtime and late evening sessions for people sensitive to cold.

Who Should Be Cautious With Cold Plunges

Even though it's a "hot" trend, cold plunges aren't for everyone. The sudden cold shock can trigger stress responses that may outweigh the benefits for certain people.

• People with heart conditions: Cold exposure can cause rapid changes in heart rate and blood pressure, which may increase cardiovascular risk.
• Individuals with blood pressure issues: The cold shock response can temporarily raise blood pressure and strain the nervous system.
• Those prone to panic or anxiety responses: Cold plunges can activate a fight or flight response, potentially worsening anxiety or triggering panic symptoms.
• Anyone with sleep disorders worsened by adrenaline spikes: Cold exposure increases alertness hormones, which may delay sleep onset or disrupt sleep quality when done too close to bedtime.

If any of these apply, cold plunging should only be considered with medical guidance.

Safety Considerations

Cold plunges can be great for your health, but safety should always be a top priority. If you have any medical conditions, talk to your doctor before trying it. Beginners should start slow—an ice-filled bathtub at home is an easy way to let your body adjust to the cold gradually.

Final Thought

Cold plunges are a growing wellness trend, known to support muscle recovery, boost mood, and even improve sleep. As more people add cold exposure to their routines, it’s helpful to understand how timing can affect sleep.

Whether you’re an athlete or just looking to feel refreshed, cold plunges can be an energizing addition to your wellness habits.