We know that getting moving is one of the best things we can do for our bodies. The benefits are almost endless: improved insulin resistance & cardiovascular health, good for our muscles & 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 immunological changes may not be that much of a big deal. Surely it is fat loss and muscle gain that are the desired outcomes of exercise? But I’d argue otherwise.
WHY OUR IMMUNE SYSTEM IS SO SPECIAL
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.
Movement of lymph fluid through the lymphatic vessels transports immune cells around the body where they seed the tissues 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. Movement for our immune health starts with the lymphatic system – the circulatory system of our immunity. 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 movements propelling the fluid along network. The lymph fluid, called chyle, permeates every nook of our body – even mixing with the brain and spinal fluid.
WHAT HAPPENS WHEN THE LYMPS ARE DISRUPTED?
Like any system in the body, problems can occur when the daily flow of the lymphatics are disrupted. Being sedentary is a shortcut to low immune function, leaving you open to infections.
Stress causes a remodelling of lymphatic vessels which can have health consequences due to impairing then proper drainage of tissues. 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 decreases our circulating immune cells.
Diet can also impact our lymphocytes: altering your body composition to far from its healthy set point, salt imbalance, poor digestion and an out-of-whack gut microbiome all impact the lymphatics. As well as being the core operating system for our immunity, is also functions to maintain fluid balance, remove cellular waste products and absorb essential fats and nutrients (including vital fat-soluble micronutrients such as vitamin A, D, K and E) from our digestive tract.
The recent discovery in 2016 of the brain lymphatics overturns decades of what we once thought we knew about the lymphatic system – 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. The activity of the brain lymphatics is particularly active while we sleep, and not just any sleep but at least 20% should be deep restorative phases of the nature sleep cycle.
Main functions of the lymphatics:
- 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.
- Transporting 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 & 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 are sent off to the liver for processing.
Ways to activate your lymphatics:
Movement– 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. Exercise is the most potent activator of nitric oxide production. It’s been shown that as little as 20 to 30 minutes of aerobic exercise is enough to increase nitric oxide levels to have positive effect on lymphatic flow, particularly if you breathe through your nose.
Deep breathing – 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. Combine with gentle stretching can also be a nice way to self-manage stress and relieve tension at the end of the day.
Rebounding– Lymph 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 toward the center of your body. Do this along with your arms, then gently brush your stomach and back.
Lymphatic massage– Often referred to as lymphatic drainage, was developed for the treatment of lymphedema (lymphatic blockage leading to painful swelling). While the technique may vary, it generally involves the practitioner manipulating the body to physically drain the lymphatic fluid and it does produce tangible evidence-based results. A recent study also showed that a combination of lymphatic drainage massage and exercise were beneficial in the treatment of conditions that involve blocked lymphatics.
Hydrate – Dehydration is a common cause of lymph congestion. Lymph becomes thicker and less mobile when you are dehydrated so make sure to drink to thirst.
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 have access to a sauna, a hot and cold shower at home is a handy way to recreate the lymphatic nourishing properties at home.