Microbiome and Movement
- 1 Introduction
- 2 Human Microbiota and Human Microbiome
- 3 Factors affecting the gut microbiome
- 4 Implications for Physiotherapy
- 5 Concluding remarks
- 6 References
The human body is made of trillions of cells, which group together to form different tissues and organs. But humans are not entirely humans. The human body is host to many millions of microbes. In fact, microbes are the most numerous and diverse organisms on Earth. They are present everywhere, in the air, soil, plants, animals, under the earth. A human body is an ecosystem, and each of us carries an incredible diversity of microbes.
Studies now reveal that exercise can have a very beneficial effect on the gut microflora.
Human Microbiota and Human Microbiome
Human microbiota is a community of microbes residing in and on the human body. It consists of the 10-100 trillion symbiotic microbial cells harboured by each person, primarily bacteria in the gut. It refers to the entire population of microorganisms that colonizes a particular location; and includes not just bacteria, but also other microbes such as fungi, archaea, viruses, and protozoans.
The human microbiome is genes carried in that microbiota. The gut microbiota has even been considered to be an “essential organ” carrying approximately 150 times more genes that are found in the entire human genome.
Chronic diseases such as obesity, inflammatory bowel disease, diabetes mellitus, metabolic syndrome, atherosclerosis, alcoholic liver disease, nonalcoholic fatty liver disease, cirrhosis have been associated with human microbiota. Microbiome projects worldwide have been launched with the goal of understanding the roles that these symbionts play and their impacts on human health.
Development of Microbiome
The relation between the gut microbiota and human health is being increasingly recognized. It is now well established that a healthy gut flora is largely responsible for the overall health of the host. The normal human gut microbiota comprises of two major phyla, namely Bacteroidetes and Firmicutes. Though the gut microbiota in an infant appears haphazard, it starts resembling the adult flora by the age of 3 years. There exist temporal and spatial variations in the microbial distribution from the oesophagus to the rectum all along the individual’s lifespan. Developments in genome sequencing technologies and bioinformatics have now enabled scientists to study these microorganisms and their function and microbe-host interactions in an elaborate manner both in health and disease states.
Functions of the gut microbiome
The normal gut microbiota imparts specific function in:
- host nutrient metabolism,
- xenobiotic and drug metabolism,
- maintenance of structural integrity of the gut mucosal barrier,
- immunomodulation, and
- protection against pathogens.
Factors affecting the gut microbiome
Several factors play a role in shaping the normal gut microbiota. They include:
Mode of delivery
Mode of delivery (vaginal or cesarean) baby's first microbes primarily come from his or her mother's vaginal microbiome (the lactobacillus, which is a genus of bacteria containing many species that are important for human health) and for a newborn delivered by C-section, the baby's first microbes resembles those microbes found on the human skin. It is now seen that Cesarean births are also associated with higher rates of a broad range of diseases, including asthma and food allergies. Some of these issues could be attributed to microbes. but it's an active area of research.
Diet during infancy
Diet during infancy (breast milk or formula feeds) and adulthood (vegan-based or meat-based):-beneficial bacteria in a baby's intestinal tract come directly from mother's milk, and from skin contact while breastfeeding. Processed food lacks fibre, and it suppresses gut microflora thereby causing allergies, inflammatory conditions. A plant-based diet rich in fibre is good for gut flora.
Use of antibiotics
The use of antibiotics can destroy the bad as well the good microbes and that it may take a year to recolonize the good microbes in the gut. Reduced variation in microbiota has been associated with these health problems, while increased diversity has been linked to a favourable metabolic profile and immune system response.
Effect of environment
A clean, dirt-free environment can destroy the microbiome. Microbiome can be preserved and protected by avoiding harsh laundry products, antibacterial soaps, and hand-wash, shampoo which target the skin and mouth microbiome.
Effect of exercise
Exercise influences the gut microbiota, stimulating the development of gut bacteria. A major study conducted on elite rugby players demonstrated that exercise enriched the diversity of gut microflora(greater diversity among the Firmicutes phylum that helped to maintain a healthier intestinal environment) and positively correlated with protein intake and creatine kinase levels. These results indicated that both diet and exercise determined the microbial biodiversity of the gut. The study published in Microbiome in 2016 shows that cardio-respiratory fitness is correlated with increased microbial diversity in healthy humans. The microbial profiles of fit individuals favour the production of butyrate. As increased microbiota diversity and butyrate production is associated with overall host health, the findings warrant the use of exercise prescription as adjuvant therapy in combating dysbiosis-associated diseases. Exposure to sunlight also alters the gut microbiome. A study showed that vitamin D deficiency changes intestinal microbiome, reducing the vitamin B production in the intestine, thereby adversely affecting the immune system, causing pro-inflammatory state associated with autoimmunity and atherosclerosis.So exercise and dietary Vitamin B and D supplementation can be used as a therapeutic intervention in the management of inflammatory and autoimmune conditions.
Implications for Physiotherapy
As health care professionals promoting exercise and physical fitness we should be educating our clients about this added bonus exercise delivers. Exercise can be used as a treatment to maintain the balance of the microflora or to re-balance eventual dysbiosis (impaired microbiota), thus obtaining an improvement of the health status.
Physiotherapists see a diverse range of health conditions many of which can directly benefit from these findings. These include, but are not limited to,
- non-intestinal autoimmune disease (eg DM1, SLE, MS)
- intestinal autoimmune diseases (eg Crohn's disease)
Further studies are needed to fully understand the mechanisms that determine changes in the composition and functions of the microflora caused by exercise and all their related effects. Movement enriches microflora diversity and overall health.
Just another substantial reason to promote exercise for overall health and well being!
- Ursell LK, Metcalf JL, Parfrey LW, Knight R. Defining the human microbiome.https://www.ncbi.nlm.nih.gov/pmc/articles/PMC3426293/ Nutrition reviews. 2012 Aug 1;70(suppl_1):S38-44.
- Dr Craig Mortensen Exercise and gut bacteria. Available from:https://www.youtube.com/watch?v=puNmUQaeSCwe ( last accessed 28.2.2019)
- Wang B, Yao M, Lv L, Ling Z, Li Lhttps://www.sciencedirect.com/science/article/pii/S2095809917301492?via%3Dihub. The human microbiota in health and disease. Engineering. 2017 Feb 1;3(1):71-82.
- Jandhyala SM, Talukdar R, Subramanyam C, Vuyyuru H, Sasikala M, Reddy DN. Role of the normal gut microbiota.https://www.ncbi.nlm.nih.gov/pmc/articles/PMC4528021/ World journal of gastroenterology: WJG. 2015 Aug 7;21(29):8787.
- Clarke SF, Murphy EF, O'sullivan O, Lucey AJ, Humphreys M, Hogan A, Hayes P, O'reilly M, Jeffery IB, Wood-Martin R, Kerins DM.https://www.ncbi.nlm.nih.gov/pubmed/25021423Exercise and associated dietary extremes impact on gut microbial diversity. Gut. 2014 Apr 26:gutjnl-2013.
- Estaki M, Pither J, Baumeister P, Little JP, Gill SK, Ghosh S, Ahmadi-Vand Z, Marsden KR, Gibson DL. Cardiorespiratory fitness as a predictor of intestinal microbial diversity and distinct metagenomic functions.https://microbiomejournal.biomedcentral.com/articles/10.1186/s40168-016-0189-7 Microbiome. 2016 Dec;4(1):42.
- Gominak SC. Vitamin D deficiency changes the intestinal microbiome reducing B vitamin production in the gut. The resulting lack of pantothenic acid adversely affects the immune system, producing a “pro-inflammatory” state associated with atherosclerosis and autoimmunity.https://www.ncbi.nlm.nih.gov/pubmed/27515213 Medical hypotheses. 2016 Sep 1;94:103-7.
- Opazo MC, Ortega-Rocha EM, Coronado-Arrázola I, Bonifaz LC, Boudin H, Neunlist M, Bueno SM, Kalergis AM, Riedel CA. Intestinal microbiota influences non-intestinal related autoimmune diseases. Frontiers in microbiology. 2018 Mar 12;9:432.
- Chen J, Guo Y, Gui Y, Xu D. Physical exercise, gut, gut microbiota, and atherosclerotic cardiovascular diseases. Lipids in health and disease. 2018 Dec;17(1):17.
- Monda V, Villano I, Messina A, Valenzano A, Esposito T, Moscatelli F, Viggiano A, Cibelli G, Chieffi S, Monda M, Messina Ghttps://www.ncbi.nlm.nih.gov/pmc/articles/PMC5357536/. Exercise modifies the gut microbiota with positive health effects. Oxidative medicine and cellular longevity. 2017;2017.