How does inflammation affect your ability to build muscle?
Kelsey Brown, BSc
February 15, 2023
What is inflammation?
Inflammation is a natural response that happens when your body detects foreign and harmful stimuli (such as disease-causing bacteria, toxins, or physical injury) which may cause damage to your tissues. Your immune system senses these stimuli and releases inflammatory cells and cytokines which are signalling molecules that stimulate other immune cells and coordinate an immune response, in this case, they stimulate more inflammatory cells. This defence mechanism helps to remove foreign/harmful stimuli before aiding the healing process to return the body back to normal.
Inflammation can be acute or chronic. Chronic inflammation is long-term inflammation which can last for several months or even years and can be caused by autoimmune disorders such as rheumatoid arthritis, recurring bouts of acute inflammation or the body’s inability to remove acute inflammation such as infections. This produces an inflammatory response which may last for a long period and could result in tissue damage.
Acute inflammation is shorter-term inflammation which may last for a few days. Some symptoms are redness, pain, and swelling. This type of inflammation can happen in response to tissue damage experienced from trauma and can come as a result of a minor injury such as cutting your finger or as a result of the damage that occurs in the working muscles following exercise. Inflammation aids the healing process following this trauma.
How can inflammation help you build muscle?
When you work out, your muscles are put under strain which causes small tears to form in your muscle fibres. This minor trauma results in your muscles becoming inflamed while your body works on repairing the affected area. In response to this acute inflammation, satellite cells on the outside of your muscle fibres are activated and form together to repair the damaged muscle fibre. This process leads to the development of stronger muscle fibres, allowing you to build muscle.
Your muscles need to go through the process of being damaged and then repaired to build muscle, so training regularly is important to keep this cycle going and to maintain or increase your muscle mass. However, you can experience the negative effects of excessive inflammation with too much training.
How can inflammation prevent you from building muscle?
While a certain degree of inflammation is important for building muscle, excessive inflammation can have an undesirable effect on muscle growth. By training too often without giving yourself enough time to recover, you prolong the inflammatory response from your previous workout, without giving it an opportunity to resolve. Regularly overtraining in this way causes a cycle of unresolved damage and can lead to longer-lasting chronic inflammation, which can then negatively affect other areas of your body such as your joints.
Delayed onset muscle soreness (DOMS) occurs as a result of acute inflammation caused by the small tears created in your muscle fibres following exercise and presents as pain and stiffness in your muscles. DOMS is inevitable after exercise, however, should go away after about 48 hours when your muscles have fully recovered. If you don’t give your body enough time to heal and constantly push your muscles to fatigue, you will not experience any muscle gains from the training.
Being in a constant state of soreness can cause you to overcompensate with other muscles and move in an unnatural way which puts stress on your joints and could lead to injury. So it is important to incorporate rest days in your training to allow the inflammation to settle.
When experiencing the pain associated with DOMS, you may choose to take an anti-inflammatory to help with the pain. However, it is worth noting that while this will reduce the pain, it will prevent the acute inflammation in your muscles, which could then impair your ability to build muscle as inflammation is an important part of the process.
IL-6 and muscle building
IL-6 is a cytokine which can be associated with both acute and chronic inflammation and therefore, can impact how effectively you build muscle. IL-6 is produced at the site of inflammation, in the muscles you have worked on in your training session, and can act as a pro-inflammatory cytokine and an anti-inflammatory myokine (a cytokine that is released during muscular contraction). So IL-6 production can help with muscle building via the inflammation process: acute spikes in these levels shortly after exercise can encourage muscle repair through the activation of satellite cells. However, IL-6 levels that are too high at rest could be damaging and prevent muscle gain.
Your genetics can affect your resting IL-6 levels and IL-6 activity, which has an impact on the role inflammation plays in your body. You may be more likely to experience greater muscle gains, or your ability to build muscle may be impaired as a result of differences in IL-6 activity.
Discover how your IL-6 activity can impact muscle building
Want to know if you will benefit from your IL-6 activity or if this may hinder your ability to build muscle? Inflammation and muscle growth (IL6) is just one of 135+ genetic reports that are included in your FitnessGenes DNA analysis test.
Alternatively, start unlocking your lifestyle-based reports, free of charge at https://my.fitnessgenes.com.
Chen, L., Deng, H., Cui, H., Fang, J., Zuo, Z., Deng, J., Li, Y., Wang, X., & Zhao, L. (2017). Inflammatory responses and inflammation-associated diseases in organs. Oncotarget, 9(6), 7204–7218
Costamagna, D., Costelli, P., Sampaolesi, M., & Penna, F. (2015). Role of inflammation in muscle homeostasis and myogenesis. Mediators of Inflammation, 2015, 1–14.
Henselmans, M. (2020, January 5). Inflammation: The major regulator of Muscle Growth Nobody talks about. MennoHenselmans.com. https://mennohenselmans.com/inflammation-muscle-growth/
Inflammation and muscle growth: A Primer. Innermost. https://www.liveinnermost.com/blogs/insight/inflammation-and-muscle-growth-a-primer#:~:text=Inflammation%20helps%20muscle%20growth,critical%20role%20in%20muscle%20repair.
Inflammation: What is it, causes, symptoms & treatment. Cleveland Clinic. https://my.clevelandclinic.org/health/symptoms/21660-inflammation
Lee, J. H., & Jun, H.-S. (2019). Role of myokines in regulating skeletal muscle mass and function. Frontiers in Physiology, 10.
Marcin, A. (2020, May 1). How long does it take to build muscle? Healthline. https://www.healthline.com/health/how-long-does-it-take-to-build-muscle#muscle-growth
Nash, D., Hughes, M. G., Butcher, L., Aicheler, R., Smith, P., Cullen, T., & Webb, R. (2022). IL-6 signaling in acute exercise and chronic training: Potential consequences for health and athletic performance. Scandinavian Journal of Medicine & Science in Sports, 33(1), 4–19.
Pahwa R, Goyal A, Jialal I. (2022). Chronic Inflammation. StatPearls https://pubmed.ncbi.nlm.nih.gov/29630225/