Benefits of exercise
Getting moving is one of the best things we can do for our bodies. The benefits are almost endless: improved insulin resistance and cardiovascular health, good for our muscles and bones (especially as we age), improved cognition, mood and coordination. The list goes on. But exercise also has a profound, yet much less appreciated effect on our immunity. You may think that exercise associated immunological changes aren’t a big deal. Surely it is fat loss and muscle gain that are the desired outcomes of moving our bodies? I’d argue otherwise. Let’s take a look why:
Our Immune System
Our immune system - the complex, highly organised constellation of cells and molecules spread throughout every inch of our body. Not just for fighting infections, the immune system has an important role in incidence of lifestyle related disease, its responsible for healing and damage repair AND is actually our main cancer surveillance system. The immune system speaks a common biochemical language with all our body system including the nervous system and endocrine system, communicating via shared neurotransmitters, hormones, chemical mediators in the body. In fact, the immune system is integral part of all physiological processes even reproduction. Exercise induces has a profound impact on the ability of the immune system to carry out its many tasks. And this foundation for health and wellbeing starts with the lymphatic system.
Grand Avenues of Immunity
The role of movement in our immune health starts with the lymphatic system – the circulatory system of our immunity - a network of vessels and nodes that spans the entire body. It is critical for good health and for our immune system to function properly. While we tend to focus more on the blood circulatory system, the lymphatics have become somewhat neglected. Both blood and lymphatic systems share many functional, structural and anatomical similarities, but lymphatics are unique. Unlike the blood system, which is a closed loop with the heart actively pumping blood to oxygenate our tissues, lymphatics are open-ended. Movement of lymph is governed by our rhythmic daily muscle movements propelling the fluid along network. The lymph fluid, called chyle, which contains our immune cells, permeates every nook of our body – even mixing with the brain and spinal fluid. Movement of lymph fluid through the lymphatic vessels transports immune cells around the body, where they patrol all the remote corners of our body, keeping a lookout for anything untoward. The lymphatics also bring immune cells together in hubs of immune activity called lymph nodes. Surveillance of our body for infection and potentially cancerous cells is a critical daily immune cell task. If the flow of lymph stops or becomes impaired, this vital immune surveillance and defence function can also become compromised.
Like any system in the body, problems can occur when the daily flow of the lymphatics are disrupted. We know that being sedentary is a shortcut to low immune function, leaving you open to infections. Being sedentary can increase risk of being at an unhealthy weight and studies have shown that obesity markedly decreases lymphatic function. Getting your body moving, independent of weight loss, decreases lymphatic inflammatory markers improves lymphatic function, reversing some of the unhealthy changes accumulated through sedentary behaviour. We now know that in individuals with type 2 diabetes, the walls of the lymphatic system become leaky, impairing their ability to do their job properly, leaving us open to infection. This dysfunction can also contribute to high blood pressure and stimulates growth of fat cells, altering your body composition from its healthy set point. Diet can also impact our lymphatics: salt imbalance, poor digestion and an out-of-whack gut microbiome all impact the lymphatics which intimately support with our digestion and absorption of nutrients. As well as being the core operating system for our immunity, the lymphatic system also maintains fluid balance, removes cellular waste products and absorbs essential fats and nutrients (including vital fat-soluble micronutrients such as vitamin A, D, K and E) from our digestive tract.
Inflammation is a normal and vital component of our immune defence against infection. It is response and lymphatics. Inflammation causes expansion of the lymphatic network and weakening of its ability to carry immune cells, leaving us vulnerable to infection. This also encourages the lymphatics to deposit fat tissue at the site of inflammation. Accumulation of fat tissue and macrophage infiltration are associated with the progression of inflammation.
Stress causes a remodelling of lymphatic vessels and impairs the proper drainage of tissues, which can have negative consequences for our health. Chronic exposure to large surges of cortisol, the stress hormone, can literally cause the lymphoid tissue to atrophy. Persistently high levels of the stress hormones cortisol have been linked to suppressed immune system function and reduced circulation of the antibodies the body desperately needs to fight off foreign invaders. In the hours following a stressful event, cortisol reduces the amount of circulating immune cells, putting a pause on generation of new ones.
The recent discovery of the brain lymphatics overturns decades of what we once thought we knew about the lymphatic system – it showed that the brain is actually directly connected to the immune system via vessels previously thought not to exist. This paradigm-shifting discovery alters how we perceive brain-immune interactions. Scientists have now shown that the lymphatics act as an irrigation system for the brain, with the immune system eliminating toxins from the cerebrospinal fluid bathing our brain through lymphatic vessels. This activity clears out metabolic waste products that have been linked to cognition, memory and cognitive decline. It appears to be highly influenced by physical activity and is particularly active during deep restorative phases of the nature sleep cycle.
Main functions of the lymphatics:
So we know from research that exercising makes the muscles contract and pushes the lymph fluid through the body. This assists in the lymphatic vessels playing multifaceted roles in the body which can be grouped into 3 main areas:Circulatory super highways of the immune system: When the lymphatic system is congested as a result of acute stress, sedentary lifestyle or poor digestion, the lymphatic system’s ability to circulate can be adversely affected compromising our immune surveillance.
Circulatory super highways of the immune system: This surveillance role allows the immune cells to keep an eye out for infections or potentially cancerous cells. When the lymphatic system is congested as a result of genetic issues, acute stress, sedentary lifestyle or poor digestion, the lymphatic system’s ability to circulate can be adversely affected.
Transporting dietary fats and fat-soluble vitamins from the intestine to every corner of the body: When the lymphatics are not flowing, we may feel our energy levels drop. Fat soluble vitamins are not transported from the digestive tract around our body.
Detox-channel for cellular metabolites and low-grade inflammation: Waste products from the day-to-day running of the cells in our body, toxic by-products from pesticides and environmental pollutants that are too big to enter the bloodstream all end up being collected into the larger lymphatic vessels that line the intestinal tract, and are sent off to the liver for processing.
Maintaining whole body fluid balance: As blood carries nutrients and oxygen around the body, fluid diffuses out into our tissues. One of the principal functions of the lymphatic system is to gather this fluid and return it to the blood system to maintain overall fluid balance. Swelling, known as lymphedema*, occurs when this fluid accumulates in a certain area of our body such as a limb. Over time, persistent lymphedema can lead to complications that affect the function of that body part such as inflammation, fibrosis (a kind of scarring) and deposition of fatty tissue.
*Lymphedema can be due to a specific genetic condition (known as primary lymphedema) or due to surgery, certain infections and various lifestyle factors including lack of physical activity. and fat-soluble vitamins from the intestine to every corner of the body: When the lymphatics are not flowing, we may feel our energy levels drop. Fat soluble vitamins are not transported from the digestive tract around our body.
Ways to activate your lymphatics:
As knowledge of our lymphatic system has grown, so has interest in combining therapeutic techniques with body movement—though, for many years, researchers made no connection between body movement and the lymphatic system? At the beginning of the 19th century, a system of therapeutic gymnastics was popularised, designed to maintain physical condition and health. Followed by a German gymnastics system called turnen, which can be roughly translated as “movement.” We now know that movement is vital to the health of our lymphatics and therefore a proxy to a healthy immune system. Forces from the movement of our muscles helps maintain a healthy lymphatic flow and exercise is a proven and safe way to treat swelling associated with lymphatics. One critical regulator of lymphatic flow is nitric oxide (NO), a molecule that also mitigates the damaging effects of inflammation and regulates our blood pressure. Exercise is the most potent activator of nitric oxide production. It has been shown that as little as 20 to 30 minutes of aerobic exercise is enough to increase nitric oxide levels and to have a positive effect on lymphatic flow, particularly if you breathe through your nose.
Just as the heart is the pump for the circulatory system, the diaphragm can assist in pumping the lymphatic system. Deep diaphragmatic breathing is the most important facilitator of lymphatic function. Combined with gentle stretching this can also be a nice way to self-manage stress and relieve tension at the end of the day.
Vegetables—notably leafy green vegetables and beets—contain nitrate, which can be converted in the body to nitric oxide which regulates lymphatic flow. Many plant foods, including fruits, chocolate, and red wine, also provide polyphenols and other compounds that can increase nitric oxide production. High-protein foods such as nuts, beans, seeds, turkey, seafood, and dairy products supply arginine, which is an amino acid (one of the building blocks of protein), used by cells to make nitric oxide.
Lymph fluid responds very well to G-forces, which is why it can be useful to use mini-trampolines, often called rebounders. Gentle up and down bouncing activates lymph flow. The gravitational pull caused by the bouncing causes the one-way lymphatic valves to open and close, moving the lymph and your immune cells all around the body..
Dry skin brushing (effleurage)
Dry skin brushing naturally exfoliates the skin to remove dead skin cells and clear oil, dirt and residue from pores that contribute to dull, dry, congested skin. The gentle pressure and movement of the bristles may also help stimulate lymph flow to gently detoxify the body. Dry skin brushing proponents also claim that it helps reduce cellulite by improving blood flow to the skin. To dry skin brush, begin at your feet and brush upwards with long, smooth strokes, always brushing towards the centre of your body. Do this along your legs and arms, then gently brush your stomach and back. .
While lymphatic massage techniques may vary, it generally involves the practitioner manipulating the body to physically drain the lymphatic fluid, and it does produce tangible evidence-based results. Often referred to as lymphatic drainage, this was developed for the treatment of lymphedema (lymphatic blockage leading to painful swelling). A recent study showed that a combination of lymphatic drainage massage and exercise were beneficial in the treatment of conditions that involve blocked lymphatics following surgery. Massage also attenuates chronic inflammation and helps aid recovery from injury.
Dehydration is a common cause of lymph congestion. Lymph becomes thicker and less mobile when you are dehydrated so make sure you drink whenever you’re thirsty..
Alternative hot-cold Hydrotherapy
Lymphatic vessels contract when exposed to cold and dilate in response to heat. If you don’t fancy running into the sea in winter or don’t have access to a sauna, a hot and cold shower at home is a handy way to recreate the lymphatic nourishing properties at home e.