In the pursuit of performance and wellbeing, recovery is no longer an afterthought. At ThermoX, we believe recovery should be as intentional and considered as your training. One of the tools leading this movement is cold water immersion, more commonly known as ice baths.
But what does the research actually say about ice baths, and why are athletes, wellness enthusiasts and busy professionals turning to them?
Let’s look at what the evidence supports, and where it is still unclear.
What Is Cold Water Therapy?
Cold water therapy involves immersing the body in cold water, often somewhere between 10 and 15°C, for a short time. The practice has been used for centuries, and researchers are now studying what it can and cannot do for the body and mind. If you are unsure where to start, our cold plunge temperature guide explains common ranges.
1. May Reduce Muscle Soreness
One of the best-known reasons people use ice baths is to ease muscle soreness after hard exercise.
A Cochrane systematic review (Bleakley and colleagues, 2012) pooled 17 small trials and found some evidence that cold water immersion reduced delayed onset muscle soreness (DOMS) compared with resting, at points from 24 to 96 hours after exercise. The authors rated the quality of the studies as low, so the effect should be seen as possible rather than proven.
If building muscle is your main goal, timing matters. A 2024 meta-analysis in the European Journal of Sport Science suggested that cold water immersion straight after resistance training may blunt muscle growth. Our guide to cold plunging after strength training covers this in more detail.
2. Inflammation: More Complicated Than It Sounds
Ice baths are often said to reduce inflammation, but the picture is not that simple.
A 2025 systematic review and meta-analysis in PLOS ONE (Cain and colleagues, 11 trials) found that markers of inflammation actually rose immediately after cold water immersion and at one hour, which the authors described as an acute inflammatory response. Inflammation is also part of how the body adapts to training, so dampening it is not automatically a good thing. Cold does reduce how warm and sore an area feels in the moment, which is why many people find it soothing.
3. A Test of Mental Resilience
Stepping into an ice bath is as much a mental challenge as a physical one.
Cold water triggers the body’s stress response, and you have to work to slow your breathing and stay calm. Many people find that practising this regularly helps them feel more composed under pressure, and value the sense of discipline it brings.
Many practitioners compare the experience to a form of meditation under stress.
4. What Cold Does to Your Circulation
Cold water causes the blood vessels in your skin to narrow. According to the RNLI, this raises blood pressure and makes the heart work harder, and the sudden chill can trigger an involuntary gasp and fast breathing. This is known as cold water shock.
When you get out and warm up, the vessels in your skin open again and you will often notice your skin flush. This is a normal response, but it is also why cold water is not suitable for everyone, and why it is worth reading the safety note below before you start.
5. The Immune System: Evidence Is Limited
You may have read that cold exposure strengthens your immune system. The current evidence does not support a confident claim.
The 2025 PLOS ONE review found no significant changes in immune markers after cold water immersion. One large trial included in the review reported fewer self-reported sickness absence days among people who took cold showers, but that is a single study and more research is needed.
6. Mood and Stress
Many people say they feel more awake and upbeat after a few minutes in cold water.
The research is more mixed. The same PLOS ONE review found that self-reported stress was lower 12 hours after cold water immersion, but it did not find an improvement in mood overall. Cold water is not a treatment for anxiety or depression, so if you are struggling with your mental health, please speak to your GP.
7. Sleep Quality
Some people find an evening plunge helps them wind down, while others feel too alert afterwards.
The PLOS ONE review reported improved sleep quality in the small number of trials that measured it, but the authors noted the evidence is limited, with few studies, small samples and mostly male participants. Treat any effect on sleep as something to test for yourself.
How to Safely Take an Ice Bath
If you’re new to cold therapy, start gradually:
- Begin with 1 to 2 minutes at a moderate cold temperature
- Focus on slow, controlled breathing
- Build up slowly, and only if you feel comfortable
- Always listen to your body
There is no need to chase long sessions. Our guide on how long to stay in a cold plunge explains what research protocols use and how to progress.
A quick safety note: speak to your GP before trying cold water immersion if you have a heart condition, high or low blood pressure, are pregnant, or have any other medical condition. The RNLI warns that water below 15°C can cause cold water shock, so start warmer and shorter, get in slowly, and never plunge alone or after drinking alcohol.
Consistency is more important than intensity.
The Future of Recovery Is Cold
Ice baths are no longer reserved for elite athletes. They are becoming part of many people’s everyday wellness routines.
At ThermoX, we’re redefining recovery as a premium experience, where performance meets precision and discipline meets design. For more on getting started, visit our cold plunge guide.
Because recovery isn’t just about feeling better.
It’s about becoming better.