When should athletes use cold water immersion?

Cold water therapy has surged in popularity over the past few years, with people regularly taking ice baths, cold plunges, or going winter/cold water swimming. What was once reserved for elite athletes as a recovery tool, has become a mainstream wellness ritual.

However, having trained as a cold water therapy practitioner and learnt how our physiology reacts to the cold and what the research currently tells us about safe or healthy limits, simply exposing yourself to cold water without a clear intention or strategy won’t automatically deliver the benefits you may have heard about.

Cold water is a powerful tool. Like any tool, its effectiveness depends entirely on how you use it (the dose and frequency), and what your goals are.

One of the most well documented effects of cold water immersion (CWI) is its ability to reduce inflammation in the body. A type of protein called TNF Alpha is released by the immune system during cold water immersion to inhibit inflammatory signals. When you immerse yourself in cold water, TNF Alpha helps constrict blood vessels to limit swelling and tissue breakdown, which provides relief to sore muscles after exercise. It also interacts with pain receptors, reducing your perception of pain caused by muscle soreness. Once you warm back up, circulation improves, aiding recovery. This is one reason athletes have relied on ice baths for decades.

Cold water immersion can also terach you to regulate your nervous system when in discomfort (the cold) to improve mental resilience and train your stress response.

Cold exposure also activates what are known as cold shock proteins. These proteins play a role in cellular repair and protection, helping the body adapt to stress at a deeper level. This is where cold water therapy begins to move beyond simple recovery and into long-term resilience and health.

However, for athletes, context matters and cold water immersion should be targeted to your training goals.

Research suggests that cold water immersion can provide short-term performance benefits for endurance athletes like cyclists, runners, swimmers/triathletes. By reducing muscle soreness and perceived fatigue, athletes can often return to training sooner and maintain a higher frequency of intense sessions. In this scenario, using cold water immediately after exercise can be a useful strategy.

But if your goal is to build muscle, the approach needs to change.

Strength and hypertrophy rely on a process of stress and adaptation. When you train, particularly with resistance training using weights, you overload the muscles, creating micro tears in muscle fibres. The body then repairs and rebuilds that tissue stronger than before. Immediate cold exposure can blunt this adaptive response by reducing the very inflammation and muscle protein synthesis that triggers this process. For this reason, athletes who are focused on muscle hypertrophy (growth) should avoid cold water immersion immediately after training. Instead, it’s advisable to wait at least four to six hours post-exercise before exposing the body to cold, or do it on a non-strength training day. This allows the initial adaptation processes to take place before introducing cold as a recovery tool.

So where does this leave the everyday person?

It comes down to intention. Are you using cold water to recover faster from training? To build resilience by teaching your nervous system to stay regulated during discomfort, therefore training your stress response? To support mental health or boost physical health? Or simply because it’s trending? Cold water therapy is not a one-size-fits-all practice. Used with purpose, it can enhance performance, support recovery, and improve overall well-being. Used without direction, it risks becoming just another trending habit with limited return.

As with any therapeutic modality, the key is understanding the “why” behind the practice. Then you can set the dose and frequency to meet your goals.