Cold water immersion (CWI) therapy has been reported to offer distinct health benefits, with numerous health influencers, fitness sites, and medical studies offering confirmation of its benefits. However, we wanted to look at the science behind CWI therapy to help determine how effective it can be in improving performance. Are there benefits? Let’s take a look below, as we cover the research and ask, can cold water immersion improve recovery and aid in performance development?
What is Cold Water Immersion
CWI therapy is the practice of using water that’s around 59°F (15°C) to treat health conditions or stimulate health benefits. It’s also known as cold hydrotherapy. Hydrotherapy is one of the basic methods of treatment widely used in the system of natural medicine, which is also called water therapy, aquatic therapy, pool therapy, and balneotherapy.
Reported Benefits of CWI
Scanning both popular and research literature, there are several reported CWI benefits. These include:
- Reduce swelling
- Reduce painful sensations in association with muscle pain
- Reduce the feeling of fatigue
- Regulate localized blood flow
- Regulate localized tissue and internal temperature
- Regulate heart rate
- Reduce muscle spasms
- Reduce inflammation
- Reduce muscle damage
- Improve range of motion
Research Findings of CWI
In reviewing the research on CWI, CoreTek focused on the following three questions:
- Does CWI research suggest it provides benefits in recovery? (any signs it works?)
- Does any CWI research suggest it provides benefits in excess of other recovery means? (does it have anything special that other techniques cannot provide?)
- Are the requirements of any effective CWI therapy within the capability of the traditional athletes? (if it does work, can the average person implement the therapy?)
Our review of research found multiple journals with recent, or relatively recent, studies that assess CWI, either on its own, or as part of a larger review of hydrotherapy effectiveness.
Does CWI Provide Recovery Benefits
According to a study of evidence-based effects of hydrotherapy published in the North American Journal of Medical Sciences, cold exposure to a small surface area produced compensatory vasodilatation in the deeper vascular system resulting in increased blood flow to the tissues underlying the site of the exposure. The same study found that immersion at 14°C increased the metabolic rate by 350 %, heart rate by 5 %, systolic blood pressure by 7 %, and diastolic pressure by 8 %. Additionally, plasma noradrenaline increased by 530 % and dopamine concentrations by 250 %. Repeated CWI was associated with a reduced frequency in infections, increased peak expiratory flow, lymphocyte counts, and expression of gamma-interferon. Lastly, the study noted that CWI < 15°C, which is one of the most popular methods used after exercise, significantly lowered ratings of fatigue and potentially improved ratings of physical recovery immediately after immersion with a reduction in delayed onset muscle soreness at 24, 48, 72, and 96-hour follow-ups.
A more recent study in the Journal of Physiology that compared the effect of CWI and active recovery on inflammatory and cellular stress responses in skeletal muscle suggested that CWI is no more effective than active recovery for minimizing the inflammatory and stress responses in muscle after resistance training. In this study, participants were provided CWI five minutes after the training session or an active recovery consisting of low intensity using a stationary bike. Blood and tissue samples were taken 30 minutes, and 1, 2, 24, and 48 hours after exercise, and were compared to pre-exercise samples. The authors concluded that current findings do not suggest CWI mitigates the stress-related signals that stimulate the cellular movement of HSPs (Heat shock proteins are a large family of molecular chaperones that are well-known for their roles in protein maturation) after exercise. One interesting aspect of the study, noted by the authors, was muscle soreness. The authors noted that a reduction in muscle soreness after intense exercise may be the most consistent effect of CWI, and that this aspect was not part of the study.
A final study we will offer is from the international journal Research in Sports Medicine. This focuses on the effects of CWI with a higher CO2 concentration (CCWI) on aerobic cycling work efficiency. The authors concluded that a reduction in heart rate following immersion was the largest at CCWI compared to the other conditions. They concluded that CCWI is an effective intervention for maintaining repeated cycling work efficiency, which might be associated with reduced blood lactate levels and heart rate.
With these studies, and other studies we considered, our view is that CWI can provide a benefit to performance training recovery – however, you should be fully aware that the effect of CWI treatments on exercise performance and recovery are distinct, and influenced by many factors including the duration, timing, magnitude, individual responses, and nature of the activity. As with training programs, there is no universal standard for therapies – what can work for one person’s physiology, may not work for another.
Does CWI Offer Unique Recovery Benefits
So if we have answered if cold water therapy can improve recovery, what are its unique benefits? Well, none – if you follow the research.
Many studies have looked at CWIs effects on weight loss, immune system improvement, body fat composition, recovery times, etc. While studies have shown that CWI can possibly impact these areas, many of the same studies identified that other recovery techniques or recovery methods produce comparable results. What we keep coming back to is the way a recovery program makes the individual feel, and in that regard, the perception of CWI, or reaction to how one physically feels as a result, may be the primary indicator of its success. In that, many studies have directly linked preference to an activity to one’s perception of its success. If CWI is a preferred recovery method, then the psychological aspect of that preference also needs to be considered.
How to Administer CWI
Using CWI therapy methods is not difficult. However, as exposure to cold can have varying reactions on each physiology, we recommend you attempt gradual exposure to cold water, before taking a (literal) plunge. Below are four basic ways to conduct CWI:
- Gradual Shower: Work up from warm, and get colder. We recommend waiting a few minutes at each temperture change, and gradually drop the temperature.
- Cold Shower: Just start at cold, and keep it there. You will likley find this helpful, and easiest to endure if you just finished an intense workout where your body temperature and metabolism are both elevated.
- Ice Bath Immersion: Add ice to water until the temperature is between 10°C and 15°C, and stay submerged for only 10 to 15 minutes.
- Short Cold Water Swim: First, follow all safety protocols for swimming. Second, be very careful in this technique, as whereas in the other techniques you can rapidly remove yourself from the cold if there are issues, swimming in cold water is not something you can easily get out of if you have have temperatue issues. A buddy system is helpful in this one.
Most important in administering CWI is to listen to your body – and if you have any health concerns – check with a physician before attempting any of these. We do not encourage you to ever start a new fitness, recovery, or nutrition program without first researching how it affects your own unique condition.
So, can cold water immersion therapy improve recovery? Generally speaking, yes. However, the research suggests its level of effectiveness, when compared to other recovery therapies is not incredibly unique. The biggest item we noted in our review of the research is how it altered the research participants’ perception of recovery. That is, it clearly improves the perception of how the body feels. We suspect that is linked to the chemical stimuli triggered by the CWI effect, notably in dopamine levels. But to offer a final caveat, there are certain medical conditions in which CWI can offer direct benefits, as several studies indicated – however, as those benefits pertained to medical conditions and not exercise recovery, we excluded those from our commentary and assessment.
As with all areas of your health, if CWI is of interest, we recommend you seek professional guidance on how best to implement new techniques into your performance training efforts. Only by working with a specialist who can answer your unique questions, and adjusts a training, nutrition, or recovery program to your unique needs will you see the most benefit.
– Train Hard!