In a prior post, we introduced sirtuins, a group of enzymes integral to various physiological functions in our bodies. We then explored natural methods for enhancing sirtuin expression, specifically through diet, with a focus on the popular SIRTfood diet.
Now, our attention turns to exercise.
Evidence suggests that physical activity stimulates sirtuin expression, leading to improved cellular processes such as enhanced oxidative metabolism efficiency, increased mitochondrial function, and the preservation of the antioxidant system (1). Over the past two decades, research has accumulated regarding the impact of exercise on sirtuins, with much of this knowledge originating from animal and cellular models, and to a lesser extent, from studies in humans, mostly in healthy individuals (1). In this post, we will share insights from a recent study examining the effects of various exercise types on sirtuins in humans. However, before delving into the relationship between sirtuins and exercise, it’s essential to understand the significance of skeletal muscles and the connection between them, exercise and sirtuins.
The connection between muscles, exercise and sirtuins
We usually think of our muscles as what helps us move but they do more than just move; they are very important for our overall health.
- Skeletal Muscle as endocrine organ- Skeletal muscle is not simply a component of our locomotor system but has been recognized as a secretory organ (2). It is responsible for releasing different substances, such as cytokines and transcription factors, into the bloodstream and helping regulate the function of our organs such as the liver, pancreas, bones and brain (2)
- Muscles Play a Key Role in Metabolism: They play an active role in controlling how our body uses energy. As they make up about 40% of our body mass they are important for sugar (glucose) processing and fat burning (1).
- Muscles Need to Be Flexible: Skeletal muscles also need to be flexible to allow for maintaining physiological functions and metabolic equilibrium – the ability to switch between using glucose and burning fat for energy (1).
So muscles play role in how our body uses energy and they need to be flexible to switch between using glucose and burning fat for energy. But what is the connection between muscles, exercise and sirtuins?
- Sirtuins and Exercise: Sirtuins are special proteins known for their influence on how our body handles glucose and fat, responds to insulin, generates energy in our cells, and maintains muscle function. When we exercise, our muscles are being stressed, and that impact sirtuins.
- Different Types of Sirtuins: As mentioned in a previous post there are different types of sirtuins found in different parts of the cells. The two types of sirtuins that are most related to exercise are SIRT1 and SIRT3. They respond to exercise in different ways. While we will focus on SIRT1 in greater detail in subsequent sections to align with scientific research, it’s important for readers not to get overly absorbed in these intricacies from a general perspective.
- Exercise Boosts Energy Production: When we exercise, the demand for energy in our cells is increased. That triggers metabolic changes, for example increase in NAD+ levels. The increased NAD+ levels result in enhanced sirtuin activity, which ultimately contributes to improved energy production and muscle function.
Scientists are studying how sirtuins and exercise are connected to better health. Understanding this connection could lead to new ways to stay healthy and protect our muscles.
Studies on sirtuin expressions and exercise
We would like to share the results of a recent study published just this month in the prestigious journal Nature investigating the SIRT1 response to exercise (3). The study is a systematic review and meta-analysis which is considered as one of the highest quality of evidence (4). For the study the authors collected all possible studies on the topic of the SIRT1 response to exercise and reviewed and analyzed the results using objective and scientific methods.
The purpose of the review was to systematically assess existing studies on exercise interventions that measure SIRT1 in apparently healthy individuals (3). The primarily objective was to understand whether exercise has the potential to increase SIRT1. Furthermore, the researchers were interested to determine what type of exercise can influence SIRT1 levels. Studies were categorized based on several factors, including the type of exercise, its intensity, duration, and whether participants were in a fasted or fed state. Additionally, it’s worth mentioning that SIRT1 levels were assessed in various parts of the body, such as skeletal muscle or blood, and different analytical methods were used across the studies. In this discussion, we won’t delve into the specific details of where SIRT1 was measured or the techniques used for its measurement.
The study has revealed two key findings (3):
1. A single session of high-intensity exercise led to an increase of SIRT1. Some types of exercises that brought a positive impact included:
- Sprint interval training
- 5 h of cycling or loaded treadmill walk
- 45 min of treadmill run
2. Repeated exercise training was found to elevate SIRT1 levels. Some of the types of exercise include:
- High intensity interval training – 3 times/week for 10 weeks
- Pilates with weights and bands – 3 times/week for 12 weeks
- Progressive full-body resistance training – 3 times/week for 12 weeks
- Water training – 3 times/week for 8 weeks
- Progressive yoga 5 times/week for 12 weeks
The findings suggest that a single session on high –intensity exercise led to an increased amount of SIRT1 (3). Repeated exercise was also found to elevate SIRT1 levels. Overall, these findings emphasize the potential of exercise to enhance overall health by boosting SIRT1 levels. The study suggests that adjusting exercise variables such as intensity, incorporating resistance exercises, or considering fasting may optimize the health benefits of exercise. It is worth noting that more studies are needed, especially considering different populations such as older individuals and those who are overweight or obese. As SIRT1 is considered a key physiological regulator of metabolism and a target for therapeutic interventions for age-related disorders, this research underscores the role of exercise in promoting health through SIRT1 modulation. It highlights the value of exercise as a strategy to enhance well-being and potentially address age-related disorders.
If you are curious to learn what other ways there are to boost sirtuins in your body make sure you don’t miss our upcoming post on sirtuin boosting supplements- do they really help?
- Vargas-Ortiz K, Pérez-Vázquez V, Macías-Cervantes MH. Exercise and Sirtuins: A Way to Mitochondrial Health in Skeletal Muscle. Int J Mol Sci. 2019 Jan;20(11):2717.
- Legård GE, Pedersen BK. Chapter 13 – Muscle as an Endocrine Organ. In: Zoladz JA, editor. Muscle and Exercise Physiology [Internet]. Academic Press; 2019 [cited 2023 Sep 14]. p. 285–307. Available from: https://www.sciencedirect.com/science/article/pii/B978012814593700013X
- Juan CG, Matchett KB, Davison GW. A systematic review and meta-analysis of the SIRT1 response to exercise. Sci Rep. 2023 Sep 7;13(1):14752.
- Ahn E, Kang H. Introduction to systematic review and meta-analysis. Korean J Anesthesiol. 2018 Apr;71(2):103–12.