The Medicine ‘YOU’ Produce During Exercise
A complex and busy image of all the Systems and Pathways that are activated by the contracting MUSCLE when you exercise at a certain intensity, frequency and duration . You are not aware of any of it, all you feel is the ‘Buzz’ after exercise. (image from journals.physiology.org)
Exercise is the REAL Polypill
150 minutes per week of exercise is advised by the British Association of Sport and Exercise Medicine report November 2018. Dedicating 30 minutes x5 days a week to have the optimal physiological benefits.
However, for someone that has not previously engaged in exercise, that may be a big ask! A good start with a 30 min brisk walk twice a week or perhaps 20 min brisk walk x3 times a week will still bring many benefits. This time period can be gradually increased to have the optimal physiological benefits.
We forget that we were born to move, we’ve evolved from hunting cave men and women, that walked, ran, hunted and climbed for their food. Yet we accept our sedentary life style as being just part of the modern era. Then it should be no surprise to us all, that cardiovascular disease, diabetes, many cancers, susceptibility to viruses and many other diseases are the consequences of this new lifestyle.
We seem to adopt a low threshold to exercise, justifying our time better spend on anythings else but exercise, making excuses to avoid it.
So if you were told that there was ‘One Pill’ that would considerably lower you risk of cardiovascular disease, diabetes, many cancers, osteoporosis, arthritic conditions, dementia, memory loss and depression amongst many other diseases, would you take it? If I told you, that this One Pill will also help your immune system to fight against bacterial and virus infections would you think twice?
Yet many of us seem to always have to justify the time spent exercising. Always contemplating where to fit exercise into our busy heavy schedules, promising ourselves that we will start tomorrow rather than starting today.
Making time to exercise is still very much perceived as a ‘luxury’, rather than a habit. Yet exercise holds many health benefits and medicinal effects to every part of our anatomy and physiology, that medication just can’t replicate. Making exercise a habit and a necessity to our health is paramount.
A recent paper by the Journal of Physiology published in April 2020 compared the effects of exercise intervention alone, with common drugs taken to reduce cardiovascular risk factors. The results of the study were astonishing, indicating that the practice physical activity and exercise (especially the contracting muscle) has a source of many drug like molecules with beneficial effects across all ages.
Research institutes all over the world are working on identification of the bioactive molecules (ingredients) and the biological systems that are candidates for mediating exercise benefits. These biological systems/ pathways are largely different to common medication.
The beneficial effects of exercise are also very much dose dependant on frequency, intensity and duration.
We have accepted over the years that eating our 5-8 pieces of fruit and vegetables a day as a necessity to stay healthy and negates ill health. So why is dedicating some time in your day to exercise still a struggle to many people?
If still not convinced that exercise should be your new habit to adopt, then maybe once we’ve delve deeper into the physiology of exercise, you will understand, learn and start!
Contracting muscle cells manufactory the “Pill”-the beneficial molecules;
The muscle is a tissue composed of cells or fibres that produce force and movement of the body. They are primarily responsible for movement and changing body positions under the control of the nervous system. Muscles can get bigger and stronger if you exercise and smaller and weaker if you don’t. Historically muscles were thought to be “dumb” and only acted by command by the nervous system but with technological advances in protein identification, skeletal muscle can now be viewed as a secretory organ.
Skeletal muscle is made up of much smaller muscle fibres. Each group of muscle fibres can produce several hundred secretory factors, including proteins, growth factors & cytokines with such secretory capacity increasing during muscle contraction and exercise training.
Cytokines: one of the many by product of contracting muscle and a large group of proteins that plays part in cell signalling. Meaning their communication with other cells “telling them what to do”. They also play a pivotal role in immune function as they mediate and regulate immunity , inflammation and the production of blood cells. They therefore impact health, wellbeing and disease.
Myokines: is a subset of cytokines which are secreted by skeletal muscle cells during muscular contraction and during exercise. Their benefit include positive metabolic adaptation, tissue repair and immune function enhancement. In a research paper in 2019 over 600 myokines to date have been identified. However only a few of them have been studied for their biological activity and function and have provided some clear evidence as being released directly from muscle contraction.
Given that muscle accounts for 40% of our total body protein, it seems reasonable to suggest that muscle derived protein secretions (Myokines) make a significant contribution to overall circulating levels of detectable protein in our blood.
Exercise Factors: are a subset of myokines, but whilst many myokines act locally within skeletal muscles itself, some known as Exercise Factors have been proven to release into the circulation during exercise and their impact goes beyond the muscle cell. There are myokines receptors on muscle, bone, fat, liver, pancreas, heart, immune and brain cells, highlighting the potential for widespread influence.
It has been proven by many research studies that regular practice of moderate intensity exercise promotes an anti-inflammatory status in our bodies. Therefore, prevents the long term development of chronic disease.
The anti-inflammatory mechanism induced by exercise has demonstrated to involve the release of the various myokines.
IL-6 (Interleukin-6): one of the many studies myokines, usually a pro-inflammatory cytokines, but when produced by contracting muscle, it has an anti-inflammatory and immunosuppressive response decreasing pro-inflammation.
It also has a pivotal role in regulating blood sugar levels and fat mobilisation. Therefore significantly in preventing obesity development.
-> Lowers inflammation in our system
-> Prevents Obesity
IL-8 (Interleukin-8): Produced during higher intensity exercise as running causes an elevation of this myokines. Which is associated with the promotion of new blood vessels from existing ones in skeletal muscles. So seems reasonable to suggest that IL-8 plays an important role in mediating the beneficial muscular adaptations in response to exercise
-> Formation of new blood cells from existing ones in muscles
IL-15: Several studies have demonstrated that IL-15 accumulated in muscle as a result of regular exercise training and it is involved in muscle development and the reduction of fat tissue mass. More recent search has shown that it is involved in an increase in bone mineral density.
-> Muscle developmen
-> Reduction in fat tissue mass
-> Increase in bone mineral density)
IRISIN: Also been linked to exercise beneficial effects to the cardiovascular, digestive and immune systems. increased levels of Irisin in the blood and brain proven to have neuroprotective role, by protecting from cognitive (brain) impairments and memory loss. Irisin also been correlated with bone mineral density and the prevention of bone loss. Further more Irisin is associated with muscle strength improvements in the elderly, so starving off Sarcopenia.
-> Brain protection and prevents memory loss
-> Prevention of osteoporosis
-> Prevention of the effects of muscle wasting/weakness due to the ageing process (Sarcopenia)
BDNF (Brain Derived Neurotrophic Factor): both acute and long term exercise stimulates an increase in the levels of BDNF in contracting muscles. Initially BDNF was studied in relation with the development and function of the nervous system (brain & spinal cord). But now we know that levels of BDNF increases with aerobic exercise, has sparked up a lot of interest in research institutes around the world.
BDNF is a myokines which regulated brain cell survival, growth and death. In addition it has been implicated with neuroplacticity (which is the brains ability to change, recognise and remodel to adapt to new circumstances and situations).
Muscle produced BDNF can act locally to help in the repair of muscle tissue. However exercise BDNF coming from other sources have been associated with improvements in depression and anxiety symptoms through different signalling pathways.
Some research institutes in Exercise Medicine have identified that exercise induced BDNF in rodents is also likely to contribute to the Anti-cancer effect of physical Activity.
-> Helps regulate brain cell survival, growth and death
-> Improvement in symptoms of depression and anxiety
-> Anti-cancer influences on our cells
FGF21 (Fibroblast Growth Factor 21) Fibroblast growth factors (FGF’s) signify proteins with diverse biological functions. It is an insulin regulating myokine that is released into the blood during exercise. Therefore protecting against diet-induced obesity and insulin resistance. It plays a role in protection against lipotoxicity the ectopic deposition of fat in the liver or muscle. GFG21 has also been proven to mediate major exercise-induced health/anti-aging benefits.
-> Helps in maintaining muscle mass
-> Helps in the prevention of Colon cancer
SPARC (Secreted Protein Acidic and Rich in Cysteine) Researchers in 2013 reported that SPARC as a novel myokine is released from the skeletal muscle of both humans and mice after exercise. It has been proven to enhance glucose metabolism and plays a role in increasing muscle size (Hypertrophy). This means it has an important role in reversing age related muscle atrophy.
Researchers have also proven that SPARC secretions inhibit colon tumour growth, by enhancing the death of the colon cancer cells. SPARC is now in fact a potential target in cancer immunotherapy.
-> Protects against diet related obesity
-> Protects against insulin resistance and from developing Diabetes
-> Anti-aging health benefits
The above are an example of only 7 out of the 600 known myokines researched in institutes all over the world in relation to exercise and contracting muscle physiology. Advances in protein analysis, in mass spectrometry and genetic testing technology will shape the future of exercise immunology. We are only really scratching the surface in better understanding the physiological effects of exercise from helping with the following:
- Metabolic processes and prevention of long term disease
- Muscle growth
- Prevention of muscle weakness accelerated by the ageing process
- Prevention of Musculoskeletal (Muscle & joint) disease
- Prevention of obesity
- Prevention of type II diabetes
- Prevention of Cardiovascular disease
- Cancer prevention
- Prevention of mental health disease
- Lowering rate of bacteria & viral infections including Covid-19
There is no One Pill out there that can accomplish all the above health benefits. Exercise of certain duration, frequency and intensity has been proven to accomplish all of the above health benefits. Research has also demonstrated that even the small increases in physical activity of any intensity substantially reduces the risk of premature death.
Exercise is certainly advised during the Covid 19 pandemic for its enhancement of the immune system to pathogens and vaccines. This makes physical exercise an important habit to adopt in the prevention of infectious pandemics such as Covid 19 or any other future pandemics or in the non-infectious ones such as obesity, diabetes and cancers.
Consultation with a Physiotherapist or a highly trained fitness professional is recommended as exercise prescription programmes needs to be very individualised and designed according to age, clinical condition and level of fitness.
If you need any support along your journey to returning to activity and exercise, please contact firstname.lastname@example.org
Start planning today how you can adopt exercise as your new habit and your start to health & vitality.
*Research references available on request