The health benefits of regular exercise have long been established, extending across multiple organ systems and contributing to longevity, resilience, and an enhanced health span.
In 2000, researchers discovered that muscle contraction can lead to the release of a molecule known as Interleukin-6 (IL-6). With the discovery shedding light on a previously unexplored arena of exercise science, researchers began to explore the concept of ‘exerkines’.
What Are Exerkines?
Exerkines are hormones, metabolites, proteins, and nucleic acids that are are secreted in response to acute and chronic exercise. While acute exercise is usually a single episode of either aerobic or resistance exercise, chronic exercise is described as multiple exercise episodes that are performed over the course of weeks to months.
Through endocrine, paracrine and/or autocrine pathways, exerkines may be responsible for many of the established benefits of exercise, such as preventing and mitigating disease. Moreover, these signaling molecules may be capable of promoting healthy aging and increasing resilience, which is the ability of the body to resist, adapt to, recover or grow in response to stressors.
How Do Exerkines Affect Our Organ Systems?
While the initial focus of exerkine research was primarily on skeletal muscles, recent exploration of these molecules has demonstrated that they are released by and influence multiple tissues and organs within the body. A few illustrations of their their wide-ranging and systemic effects include:
In the cardiovascular system, exerkines lead to cardioprotection by enhancing vascularization and angiogenesis, and improving blood pressure, endothelial function, and overall fitness.
In adipose tissue, exerkines increase fatty acid uptake, the breakdown of fats and other lipids, energy expenditure, and glucose metabolism.
In the liver, exerkines also increase fatty acid uptake and glucose metabolism.
In skeletal muscle, exerkines enhance mitochondrial biogenesis, protein synthesis, stem cells, and capillarization to stimulate muscle regeneration.
In the quest to demystify the health benefits of exercise, our understanding of exerkines is emerging as a hopeful frontier. Alongside the potential to improve cardiovascular, metabolic, immune, and neurological health, new targets for treating cardiovascular disease, type 2 diabetes, and obesity may be found through exerkine research.
With every step, jump, and lift, we are not just strengthening muscles and burning calories – we are releasing a team of powerful signaling molecules that are a testament to the enduring truth: exercise is medicine.
- Chow, L.S., Gerszten, R.E., Taylor, J.M. et al. Exerkines in health, resilience and disease. Nat Rev Endocrinol 18, 273–289 (2022). https://doi.org/10.1038/s41574-022-00641-2