The Endocrine system is responsible for the regulation of our Hormones. Hormones are chemicals released in our bodies that control cellular functions. Hormones control a number of different reactions in the body including tissue growth, hydration levels, reproductive process, energy levels, metabolism, muscle growth, muscle loss and mood swings.
Hormones can be proteins, polypeptides, amino acids, or steroids.
It is great to understand how hormones influence muscle growth and fat metabolism so when we exercise we can make the most out of our results.
Hormones can be either anabolic, which means they help build new tissue, or catabolic, they play a role in breaking down tissue. Our hormones work together and affect one another, so a dysfunction or imbalance with one often affects many others.
INSULIN: A hormone produced by the pancreas, insulin regulates carbohydrates and fat metabolism. When your blood sugar levels are elevated after food consumption, insulin is released into the blood to promote the storage and absorption of glycogen in the liver and glucose in the cells. Insulin helps glucose by either being absorbed from the bloodstream into skeletal muscles or fat tissue. If we have excess glucose in the bloodstream and the body does not require it for fuel, it will be stored as fat in adipose tissue.
When we start exercising the sympathetic nervous system suppresses the release of insulin, so it is important if you are wanting to burn more adipose tissue throughout your workout not to consume high levels of sugar because this will elevate insulin levels and promote glycogen storage instead of it being used as a fuel source.
Glucagon is released in response to low blood sugar levels, the pancreas produces glucagon to stimulate the release so free fatty acids (FFA’s) from adipose tissue and increased blood glucose levels, both of which are very important for fuel during exercise. The liver also stores glycogen which is used for fuel when other levels deplete.
Cortisol is a catabolic steroid hormone produced by the adrenal glands in response to stress (fight or flight), low blood sugar levels and exercise. It supports energy metabolism during long periods of exercise by facilitating the breakdown of triglyceride and protein to create the glucose necessary to help fuel the activity. While cortisol helps promote fat metabolism, exercising for too long can elevate levels of cortisol to catabolise muscle protein for fuel instead of conserving it to be used to repair damaged tissues.
In addition to its role as a so-called “stress hormone” cortisol plays many key roles, it also aids in every physiologic system including blood pressure regulation, cardiovascular function, carbohydrate metabolism, inflammation and immune function.
EPINEPHRINE AND NOREPINEPHRINE
These hormones play an important role in helping the sympathetic nervous system produce energy and in regulating the body’s function during cardiovascular exercise.
Often referred to as ‘adrenaline’ because it is produced by the adrenal gland, it elevates cardiac output, increases blood sugar to help fuel exercise, promotes the breakdown of glycogen for energy and supports fat metabolism.
Testosterone is often referred to as the Male hormone, but is just as important for women. Testosterone is a steroid hormone is produced by the testes in males and the ovaries of females, with a small amount produced by the adrenal glands. Testosterone is responsible for muscle protein resynthesis and the repair of muscle proteins damaged by exercise, and also is significant in helping grow skeletal muscle.
HUMAN GROWTH HORMONE:
Human growth hormone is an anabolic hormone secreted by the anterior pituitary gland that stimulates cellular growth. It works on different receptors sites of the body
Which produces a number of responses including muscle protein synthesis responsible for muscle growth, increasing bone muscle, supporting immune system function and promoting fat metabolism. The body produces human growth hormone during sleep and is stimulated by high-intensity exercise such as heavy weight training, explosive power training or intensive cardiovascular training.
INSULIN-LIKE GROWTH FACTOR:
This hormone has a similar structure to insulin and is stimulated by the same mechanisms that produce human growth hormone. It is produced in the liver and supports the function of human growth hormone to repair protein damaged durning exercise, which makes it important hormone for promoting muscle growth.