Metabolic Fuel Mobilization is the acute physiological process of breaking down and releasing stored energy substrates, primarily glucose from glycogen and fatty acids from triglycerides, into the bloodstream for immediate use by active tissues. This process is rapidly initiated by the neuroendocrine response to stress or energy demand, such as intense exercise or fasting. Hormones like epinephrine, norepinephrine, and glucagon are the key regulatory signals that ensure adequate substrate availability to support high-performance activities. It is essential for maintaining energy homeostasis during periods of high metabolic need.
Origin
This concept is foundational to endocrinology and metabolism, stemming from the discovery of hormones like insulin and glucagon and their roles in glucose homeostasis. The understanding of how the sympathetic nervous system and its catecholamines rapidly override resting metabolic states emerged from early research on the ‘fight or flight’ response and exercise physiology. The term describes the systemic shift from energy storage to energy utilization.
Mechanism
The process is largely mediated by the binding of catecholamines (epinephrine and norepinephrine) to beta-adrenergic receptors on adipose tissue and the liver. In the liver, this binding activates glycogenolysis and gluconeogenesis, releasing glucose. In adipose tissue, it activates hormone-sensitive lipase, initiating lipolysis and the release of free fatty acids. This hormonal cascade ensures that the circulating levels of glucose and fatty acids are sufficient to meet the immediate, increased energy demands of the central nervous system and skeletal muscles.
We use cookies to personalize content and marketing, and to analyze our traffic. This helps us maintain the quality of our free resources. manage your preferences below.
Detailed Cookie Preferences
This helps support our free resources through personalized marketing efforts and promotions.
Analytics cookies help us understand how visitors interact with our website, improving user experience and website performance.
Personalization cookies enable us to customize the content and features of our site based on your interactions, offering a more tailored experience.