Cold-Water Immersion: The Science Behind the Practice | Ice Barrel

What is the hard science behind cold-water immersion therapy? Ice Barrel explores this topic in detail in this white paper. Check out the full post.

Cold therapy has a long history of documented benefits, dating back to the writings of Hippocrates around 300 B.C. Hippocrates, in “Aphorisms” indicated that cold therapy was for acute pain and swelling such as from a sprained ankle but also effective for chronic pain (Garcia et al., 2020) . Others have reconfirmed the effectiveness of cold therapy in the ensuing centuries. Over the last 30-40 years, there has been renewed interest in researching the benefits and mechanisms of cold therapy.

Most people have experience with putting ice on an acute injury such as a sprained ankle. The resulting reductions in swelling and pain are expected. Photos and videos of professional athletes soaking in baths with ice are also fairly common. Just like for the sprain, it’s not hard to imagine that the professional athletes are reducing swelling and pain in their large muscles and joints after a hard workout. Current research indicates these short-term treatments for exercise recovery are not the only benefits of cold therapy. Research into the benefits of cold therapy include proven beneficial results for a variety of chronic diseases. (Garcia et al., 2020)

Claims of long-term benefits, including stress and depression reduction and lowering of blood markers such a HDL cholesterol, are receiving more research time. However, this area could use considerably more research. One theory suggests that the current human lifestyle may be to blame for increasing medical and emotional issues (Shevchuk, 2008). While few would argue for all of the human civilization returning to hunter-gatherer times, the environmental stress such as times of cold may be critical for bioregulation. As will be discussed below, research is indicating that the Vagus nerve complex is a key mediator for the mind-body connection and feelings of well-being and relaxation.

Parasympathetic nervous system and vagus nerve stimulation

The Vagus nerve is a complex network of long nerves that connects the brain to the abdominal organs. It comprises approximately 75-percent of the parasympathetic nervous system (Tindle & Tadi, 2020). The parasympathetic nervous system controls bodily functions during rest and works to maintain the status quo. These functions include digestion and heart rate, but the parasympathetic nervous system is also implicated in mood and mental health

 

 

Direct stimulation of the nerve is a treatment for epilepsy and treatment-resistant depression (Tindle & Tadi, 2020). However, this sort of intervention would be extreme and not normally recommended medically for people who suffer from less extreme diseases.

Due to the proximity of the vagus nerve to the skin in the neck and head region, that area is under research for effectiveness in activation of the nerve and degree of treatment possible through non-invasive methods. Being a long and large nerve bundle, this presents several issues including how and where to conduct the stimulation but also how to achieve the desired results for a variety of medical issues that the vagus nerve appears to regulate. Several studies found beneficial responses by the vagus nerve for cold water immersion of the lower body including the hips. the primary reason for this was to reduce the discomfort. however, most cold therapy studies included the neck, and some included the head or part of the head with the intention of cooling the vagus nerve.

table 1 correlation to treatment purpose and use of cold therapy and number of papers identified supporting rating

Purpose for treatment correlation for beneficial effects number of articles in this paper

First Aid/Edema

Strong

5

Oft Tissue Injury

Strong

2

Xercise Recovery (Delayed Onset Muscle Soreness)

good

11

Exercise Recovery (Fatigue)

Good

7

exercise recovery (heart rate variability)

good to strong

3

sports psychology

good

13

mental health/wellbeing

good

18

stress reduction

good

5

hdl/ldl blood lipids

moderate to good

6

autoimmune disease treatment

moderate to good

11

cognitive brain function

moderate

4

Acute injuries are immediate and tend to be caused by a single traumatic event. They can be severe such as a broken bone but also includes strains, pulls, and other soft tissue injuries. an acute injury can have long-term impacts on fitness, life goals, and feeling of wellbeing. This section of the white paper focuses on exercise-related soft tissue injuries such as exercise induced muscle soreness (EIMS), delayed onset muscle soreness (DOMS), and strains.

General science

Basic advice learned in First Aid classes discusses the acronym, R.I.C.E, which stands for Rest, Ice, Compression, and Elevation. This is for the treatment of acute injuries or suspected injuries such as strains, sprains, burns, and others. The purpose is to reduce the risk for further injury, reduce injury symptoms such as swelling (edema) and pain, and to speed healing. Following the same logic, post-exercise treatment with ice and other therapies are meant to reduce muscle damage, speed recovery, and allow athletes to return to work quickly.

Cold-water immersion is one of the most popular methods for athletes to manage acute injuries related to physical exertion. As researchers have noted, treatment for exercise-related injuries including muscle soreness, is not restricted to elite athletes but also includes low-intensity exercise that results in acute injuries (Gu et al., 2021). Cold-water immersion provides the “I” and “C” of the RICE method of injury treatment with the cold water encompassing the injured area better than ice packs (and ensures better coverage of the area that may not be apparent) and the water provides compression. The compression provided by water is not as strong as can be achieved with compression boots or socks.

A common phenomenon is for a single injured area to hurt more and for other areas of injury to not have a strong pain response. This is why it is important in assessment of injuries to look beyond the area that is painful and look for other signs such as swelling and bruising for additional injuries. This can be more difficult to assess with exercise-induced injuries such as DOMS and complimentary injuries. An example of a complimentary injury is a change in gait causing hip pain due to an ankle sprain.

Post-injury

Post-injury treatment of soft tissues such as tendons, ligaments, and muscles with cold therapies is well documented elsewhere and are standard practice in the medical field. As noted above, basic first aid classes teach how and when to apply cold therapy for injuries. As such, this white paper provides limited discussion on this aspect of cold therapies.

While soft tissue injury treatment is well documented, the benefits to breaks and fractures on bones is an area that should receive additional research. One study looked at rugby athletes and newly identified osteoimmunological biomarkers that indicate that cold therapy induces bone development, referred to as remodeling (Galliera et al., 2013). While more study is needed, cold therapy may help weight-bearing and strength athletes of all levels improve bone density.

Exercise and recovery

Exercise and recovery are two areas with extensive cold therapy research. The research often focuses on elite athletes, but the results of the studies are often applicable to the “weekend warrior” and everyday athlete (Gu et al., 2021). Most research studies use elite athletes and high-intensity workouts because they are more likely to be able to detect a statistically significant result or change. Benefits would be applicable to lower intensity workouts, in general.

Athletes are constantly searching ways to recover quicker without triggering antidoping rules (Banfi et al., 2010) and to improve the quality of their recovery (L’Hermette et al., 2020). Physical exertion from an intensive workout can result in fatigue, muscle damage, and/or edema/swelling. Researchers use several indicators for evaluation of effectiveness of treatments including pain scales for delayed onset muscle soreness (DOMS), heart rate variability, and mental capacity to re-engage in exercise. Researchers use blood markers to monitor exercise stress and the potential for muscle damage. Speeding removal of these markers would indicate faster recovery with less damage (Bastos et al., 2012; César et al., 2021; Gu et al., 2021; Ziemann et al., 2014). Blood lactate concentration and creatine kinase are two such indicators of exercise stress.

Cold therapy is one of the most widely used and effective methods for reducing fatigue, DOMS, and edema (Bastos et al., 2012; César et al., 2021; Gu et al., 2021; Ziemann et al., 2014). There are several widely accepted avenues for how cold therapy is effective for exercise recovery including vasoconstriction in the area being cooled that forces out swelling and associated delayed pain as well as acting on pain receptors in nerves in the areas being treated. Ice packs to a specific body part can provide some short-term relief. However, the effectiveness is dependent on a number of factors including keeping the ice pack in place long enough and covering the entire area impacted. Other benefits, as described by Jungmann and others, would not be achieved with ice packs alone. This includes stimulation of the Vagus nerve and associated whole body benefits (Bastos et al., 2012; Jungmann et al., 2018).

Several studies found that a single whole-body cold treatment can reduce the body’s inflammatory response to exercise and that this results in reduced delayed onset muscle soreness (DOMS) and faster recovery (Pournot et al., 2011; Śliwicka et al., 2020). One researcher found that there were measurable benefits of cold therapy at the end of the evaluation period of 96 hours and that benefits such as reduction in muscle damage may last beyond that (Bieuzen et al., 2013).

In addition to physical recovery, psychological improvement and recovery are necessary for the highest levels of success in athletics. Fatigue has both physical and psychological components, either of which can result in a barrier to the athlete from performing at their best during the next competition or workout (Bleakley et al., 2012; Rowsell et al., 2011). As will be discussed in detail below, cold-water immersion therapy has been shown to improve psychological wellbeing, which results in athletes being physically and mentally prepared for their next intensive exercise session (Gu et al., 2021).

A treatment therapy referred to as contrast water therapy is alternating between cold and warm therapy. This is a common localized practice conducted by physical therapists for an acute injury site usually involving ice massage for 10-15 minutes then a heating pad for the same amount of time. Sometimes this is repeated multiple times in a single session. Applying this to whole-body recovery therapy involves using a cold therapy method such as cold-water immersion and a hot therapy such as a sauna. Several researchers have studied the effectiveness of contrast water therapy and found that there is little evidence that switching between the two is therapeutic for non-acute injuries. One researcher postulated that researchers who believed they may have found a benefit were actually just seeing the cold therapy benefit since that was typically the last treatment in their protocol (Bieuzen et al., 2013; De Oliveira Ottone et al., 2014; Hayashi et al., 1997; Kinoshita et al., 2006).

Studies indicate that the Vagus nerve, as the largest component of the parasympathetic nervous system, is a significant mediator of exercise recovery (De Oliveira Ottone et al., 2014; Hayashi et al., 1997; Kinoshita et al., 2006; Tindle & Tadi, 2020). As the purpose of the parasympathetic nervous system is to return vital organs and the body to a relaxation state, stimulation of the Vagus nerve would trigger healing and a return to resting state. Non-invasive stimulation of the Vagus nerve is most effective with cold therapy.

Heart rate and heart rate variability

Heart rate recovery and heart rate variability are two measures of exercise recovery. Heart rate during exercise and resting states has been measured for many years and used to measure fitness levels. For example, cardiovascular exercise often includes a target heart rate for different phases of the exercise. Recovery from a high heart rate during intense exercise to a lower rate during active rest indicates a strong fitness level. Similarly, a low resting heart rate indicates a high level of fitness and general health.

Heart rate monitors are common devices and have become smaller with improvements in technology, including small wrist bands. Along with heart rate, the variability between heart beats can also indicate level of fitness (Campos, 2017). A high variability, meaning the time between each heart beat varies based on the instantaneous conditions, is an indicator of good health and fitness. This seems counterintuitive but the high variability means that the body is able to respond quickly to changes and is thus more resilient. Heart rate variability (HRV) is mediated by the parasympathetic nervous system, of which the Vagus nerve represents approximately 75 percent of the system (Tindle & Tadi, 2020). This is the “relaxation” and status quo portion of the autonomic nervous system that regulates the body’s functions. Using the same devices that measure heart rate, HRV is a non-invasive way to monitor their autonomic nervous system for imbalances (Campos, 2017). In today’s society, we are generally concerned with over activation of the sympathetic nervous system, which manages the fight or flight response to stress.

When the sympathetic nervous system is overactivated, the body experiences flight or flight stress. This results in physical stress but also mental and emotional distress. Low HRV is a good indicator of depression and anxiety as well as being associated with cardiovascular disease. As discussed in detail above, the Vagus nerve comprises the majority of the parasympathetic nervous system and is responsible for the relaxation state of the body (Campos, 2017; Jungmann et al., 2018). Non-invasive stimulation of the Vagus nerve has been shown to improve HRV and reduce overall heart rate in athletic recovery but also found this would apply for people with regular daily stress (Buchheit et al., 2009; Jungmann et al., 2018). Cold-water immersion is one of the best methods for non-invasive stimulation of the Vagus nerve to reduce daily stress as well as exercise recovery and general fitness.

Bottom line for short-term and acute uses of cold therapy

Cold-water immersion has a number of short-term benefits and is especially helpful for athletes for exercise recovery. This recovery is both physical and mental, preparing them for future competitions and workouts. The scientific evidence shows there are reductions in muscle and soft tissue damage, reductions in swelling, and vasoconstriction which likely assists in removal of cellular waste.


Figure 1 Comparison of length of session (15 min equivalent for different methods) and article’s rating of benefit with 1=none, 2=low, 3= moderation, and 4=significant.

The short-term benefits of cold therapy are well accepted, but researchers are finding many benefits from long-long term use of cold therapy. Activation of the Vagus nerve and resultant rebalancing of the inflammatory response appears to be central to the long-term benefits. Increases in heart rate variability, reduction in inflammatory markers, improved blood lipid levels, better sleep, and improved feelings of well-being are areas of research (Hayashi et al., 1997; Jungmann et al., 2018; Kinoshita et al., 2006; Polizzi, 2019) . Improvements in cognitive capacity and as a treatment option for autoimmune disorders are other areas of research.

Well-being and mental capacity – mind-body connection

The feeling of well-being can be difficult to quantify because it is variable even within an individual. It is one of those things that we can recognize in others and sometimes ourselves. Science typically tackles understanding positive well-being by examining those who lack positive well-being, such as those suffering from depression. Psychological studies rarely look at physical or physiological traits as many of the pathways are not well understood. But there are scientific studies into the mind-body connection from several different perspectives. Two examples include improving athletic performance and stress management.

Athletic performance and the measure of wellbeing is discussed above as it relates to single-use of cold therapy. Sports psychology is an area that seeks to improve athletic performance by removing mental barriers. Cold-water immersion therapy provides short-term improvements in feelings of wellbeing and the ability to return to competition or the next workout in a better frame of mind (Jansky et al., 1996; L’Hermette et al., 2020; Rowsell et al., 2011; Rymaszewska et al., 2020; Szczepańska-Gieracha et al., 2014).

Outside of athletics, regular cold-water immersion therapy has a long history of therapeutic benefits. Practitioners of cold sea swimming report improved health and overall good feelings of well-being (Demori et al., 2021). A method of cold therapy while meditating, referred to as the Wim Hof method, has been studied because the practitioners are able to reduce body stress and maintain body temperature despite exposure to very low temperatures (Kox et al., 2012, 2014; Polizzi, 2019; Van Middendorf et al., 2016). Portions of this method are based on an ancient breathing and mediation practice that allows the person to consciously activate their parasympathetic system, which modern medicine considers to be autonomic and cannot be activated through conscious effort. One of the tests for this method was for the practitioners to go into a meditative state and then to be injected with E. coli to measure their immune response. All practitioners were able to engage their parasympathetic nervous system to fight off infection and the resultant inflammatory response. All of the subjects had significantly reduced symptoms compared to the general population with method founder, Wim Hof, having nearly no symptoms. This method proves a stronger mind-body connection exists than is generally accepted and that activation of the parasympathetic nervous system is central to long-term health.

A number of health benefits are associated with cold-water immersion therapy, of which feelings of wellbeing are central. Blood level markers are often used to identify if a therapy is beneficial or not. Blood lipid levels (e.g. cholesterol) and inflammatory markers are all ways to identify if a therapy has therapeutic benefits in addition to psychological benefits. Studies indicate multiple session treatments is most effective for long-term benefits. for example, sustained reductions in LDL blood lipids for two weeks after treatments of three times weekly for six weeks (Jansky et al., 1996; Rubkowska et al., 2010, 2011; Stanek et al., 2015, 2016, 2019). subjects with at least 10 treatments had significant long-term health benefits with those with at least 20 seeing better results (Lubkowska et al., 2010). This, along with the health benefits seen by practitioners of the Wim Hof method and cold sea swimming, indicate that regular and repeated use of cold-water immersion therapy provides the best long-term health benefits.

Mental health

Depression is one of the common mood disorders that affects a person’s ability to function in daily life. This is not feeling sad or down but a physiological symptom (APA, 2020). Depression may affect 1 in 6 adults during their lifetime with older adults often having depression linked to dementia (APA, 2020; CDC, 2021). Some medical conditions can cause a depressive state, including some that can be beneficially impacted by cold therapy such as cold-water immersion. Similar to autoimmune disorders such as rheumatoid arthritis, many people with symptoms of depression for greater than two weeks have inflammatory markers, specifically TNF-alpha and IL-1 (Rymaszewska et al., 2003). Their blood studies also sometimes show oxidative stress markers. In testing, patients with a number of depressive symptoms (sadness, loss of pleasure, self-criticalness, crying, loss of interest, and indecisiveness) were statistically improved two weeks after the last treatment of ten daily cold therapy sessions (Rymaszewska et al., 2020). During this study, approximately 73% of the treated patients reported feeling “recovered” across their range of symptoms prior to treatment, which compared to 28% of the control group. This indicates the cold therapy treatment caused the recovered condition as opposed to a placebo effect. Similarly, treated patients had improvement in cognitive-affective dimension and somatic dimension, meaning their mind-body relationship improved including secondary outcomes for quality of life, pain, anxiety, depression, and general mood. These findings suggest that cold therapy may be a strong supporting therapy along with pharmaceutical interventions.

Stress and anxiety can have significant effects on the ability to function in daily life. in addition to studies on depression, studies on stress and anxiety have shown improvement with cold therapy (Rymaszewska et al., 2003, 2020, 2021; Rymaszewska joanna, David Ramsey, Sylwia Chładzińska-Kiejna, 2007). Stress and anxiety will impact a person’s ability to think clearly, sometimes referred to as brain fog, and sleep. One study found that subjects with the most severe symptoms experienced the greatest relief using cold therapy (Szczepańska-Gieracha et al., 2014).

Disease treatment

Cold therapy has been a standard non-pharmaceutical treatment in Europe for over 20 years for autoimmune disorders such as rheumatoid arthritis and fibromyalgia (Hirvonen et al., 2017; Kujawski et al., 2021; Lange et al., 2008; Lubkowska et al., 2010, 2011; Metzger et al., 2000; Miller et al., 2016; Misiak & Kiejna, 2012; Rivera et al., 2018; Stanek et al., 2015). Cold therapy treatment provides relief of symptoms and is not believed to reverse disease progression, but the studies indicate that the reduction in inflammatory markers is long-term, especially with multiple treatments. See the definitions section below for a discussion on inflammatory markers including the relationship to chronic disease.

autoimmune disorders – rheumatoid arthritis

Autoimmune disorders are characterized as the immune system attacking healthy tissues and organs. There is a corresponding inflammatory response with these attacks, which are measured in the blood. Physicians look for TNF-alpha and IL-1 to identify active disease (Hirvonen et al., 2017; Kujawski et al., 2021; Lange et al., 2008; Lubkowska et al., 2010, 2011; Metzger et al., 2000; Miller et al., 2016; Misiak & Kiejna, 2012; Rivera et al., 2018; Stanek et al., 2015). The diseases and disorders are chronic and typically progress despite interventions such as medications. Similar to what is discussed above for short-term and acute benefits of cold therapy, these inflammatory markers are significantly reduced. Cold therapy appears to provide short-term benefits such as pain reduction and long-term benefits such as non-pharmaceutical reduction in inflammation. Also similar to athletes, people suffering from chronic pain reported improvements in wellbeing and people with the worst emotional and mental state prior to treatment reported better outcomes after treatment compared to those in the same study that were less afflicted (Szczepańska-Gieracha et al., 2014). Rheumatoid arthritis and fibromyalgia were among the most common diseases researched but other diseases that likely respond positively to cold therapy include chronic fatigue syndrome, ankylosing spondylitis, multiple sclerosis, mild cognitive impairment, and dementia. Studies were able to identify that cold therapy had a beneficial effect even if there were other therapies such as kinesiology and pharmaceuticals. The researchers generally concluded that cold therapy is a strong complementary treatment.

dementia

Dementia is a general term used to describe an impairment of at least two brain functions (CDC, 2021). This impairment results in a reduced ability to remember, think, and make decisions in daily life. The most common form of dementia is Alzheimer’s disease. The Center for Disease Control and Prevention (CDC) estimates nearly 14 million people in the United States will have dementia by 2060 (CDC, 2021). While dementia is not exclusively an older adult disease, it is more common in those over 65 (CDC, 2021). The US Census projects that by 2060 24-percent of the US population will be over 65 years old, up from 17-percent in 2020 (Colby & Ortman, 2015). Older adults with a family history of dementia are more likely to develop dementia but the exact causes and identification of risk factors remain an area of study.
One area of research is that there may be a chronic inflammatory response that results in the impairment of the vascular system and oxidative stress on the brain (Misiak & Kiejna, 2012). Similar to the short-term benefits to athletes for vasoconstriction and reduction of inflammation and edema, studies indicate that the brain receives similar benefits. Cold water immersion may be a cost-effective preventative measure for dementia before symptoms develop. Other research, while focused on chronic diseases such as rheumatoid arthritis, noted mild cognitive impairment of these diseases is common (Kujawski et al., 2021; Rymaszewska et al., 2021). The researchers noted that the subjects of the cold therapy treatment with mild cognitive impairment had a statistical improvement in short-term memory. This researcher also noted that cold therapy may be a potential non-pharmaceutical treatment for dementia (Kujawski et al., 2021).

Bottom Line for Evidence-Based Effects of Hydrotherapy

Inflammatory responses to daily life stressors can have a physical and mental/emotional toll on wellbeing. Chronic stress is overactivating the sympathetic nervous system as the body is in nearly constant flight or fight response. The sympathetic and parasympathetic nervous systems are in a constant push and pull for readiness versus relaxation, but the flight or fight response of the sympathetic nervous system will override the relaxation response of the parasympathetic nervous system. While this may be a preferred survival strategy, the parasympathetic nervous system, responsible for relaxation and status quo, cannot work correctly in the modern era. Research studies show that this constant stress state has long-term harm to our physical and mental/emotional well-being. The bottom line is that regular use of cold water immersion triggers the Vagus nerve, the largest component of the parasympathetic nervous system. This results in a relaxation response, resetting of the abdominal organs to a resting state, and feelings of well-being.

While this article does not provide medical or treatment advice, researchers found that a single cold-water immersion therapy session of 15 minutes at 15 degrees celsius provided statistically beneficial responses for a reduction in inflammation markers, improved athletic performance, and improved emotional feelings of wellbeing. Regular use of cold-water immersion has also been shown to provide long-term improvements in diseases such as rheumatoid arthritis and chronic depression as well as feelings of general good well-being with effects lasting more than two weeks after repeated treatments. The treatments researched ranged from daily for two weeks to three times per week for six weeks. People who practice the Wim Hof method of meditation during cold therapy and cold sea swimming report similar physical and psychological benefits. The takeaway from this is that regular use of cold therapy, when there are no underlying health issues that are counter recommended to the practice, may improve physical disease, prevent future disease, and improve outlook on life. This appears to be mediated by activation of the Vagus nerve, which connects the brain to the abdominal organs. The Vagus nerve is the largest component of the parasympathetic nervous system, which is responsible for the relaxation response and returning the body to a resting state. Ice Barrel provides a simple way to regularly have a cold-water immersion experience without requiring a membership to a facility with a cold room or access to cold sea water.

Medical Disclaimer

This white paper was developed for informational purposes only. Neither the author nor ice barrel are providing medical advice with the content of this paper. The content of the white paper was collected from reliable sources; However, it is not intended as a substitute for professional medical advice, diagnosis, or treatment. Always seek the advice of your physician or other qualified medical professional for questions you have regarding a medical condition and appropriate treatments. Do not ignore medical advice or delay seeking medical treatment based on the content of this white paper.

Cold therapy, often referred to as cryotherapy in the literature, has several different delivery methods. the delivery methods generally range from ice packs on specific body parts to full or partial body immersion in either water/ice or air.

cold-water immersion

Cold-water immersion uses several different vessels (e.g. tubes and barrels), but all allow for full or partial body immersion into water at 15 degrees Celsius (about 60 degrees Fahrenheit). Some allow for a lying or lounging position and others only permit sitting. Depending on the size, these can be found in clinical or home settings.

whole-body cold therapy

Whole-body cold therapy generally refers to cold air therapy (-110 degree C or colder) in a special chamber in a clinical setting only. Some of the chambers are designed for the subject to be lying on a hospital bed with their head outside the chamber and others are designed for the entire body to be within the chamber. (Garcia et al., 2020)

inflammatory markers

Throughout this paper, there are references to inflammatory markers. There are several different markers within blood samples that researchers look for to determine if the body is in an active inflammatory response. While some inflammatory responses can be beneficial, such as fighting off a cold, overactivation or incorrectly targeting an organ can lead to pain and permanent damage.
• Tumor necrosis factor alpha (TNF-alpha) is one of the most commonly used inflammatory markers to detect active inflammatory response. This compound is important for immune system disease and illness response, but also triggers attacks on organs, which results in diseases such as rheumatoid arthritis and others. TNF-alpha causes an inflammatory response.
• C-reactive protein is an inflammatory marker because it increases when there is inflammation, although it is not triggering the inflammation. High levels can indicate there is an active infection or chronic inflammation such as rheumatoid arthritis.
• Interleukin 1 (IL-1) is one class of many specialized proteins that are involved in inflammatory response. IL-1 causes fever, increased sensitivity to pain, vasodilation, and hypotension (drop in blood pressure).
• Interleukin 6 (IL-6) is one class of specialized proteins that are excreted during muscle contractions (e.g. exercise). Studies may use this as a marker of potential muscle damage during exercise. IL-6 is also known to be elevated in subjects with inflammatory and auto-immune disorders such as multiple sclerosis, depression, and rheumatoid arthritis.

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Jennifer Lundberg is a certified environmental professional with 29 years of experience. her area of focus is on human health including publishing her masters of environmental studies thesis on human health impacts related to aerial pesticide exposure in agriculture-dominated areas.

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