Exercise-hormone response helps keep systems in balance


The human body is complex with so many systems overlapping, working together in search of harmony and balance. When we exercise, a hormonal response begins, allowing the body to adapt and change. While there are many different hormones in the body that are responsible for multiple functions, there are hormones that are directly influenced by physical activity that can either build up or break down tissues.

The endocrine system regulates the production of hormones that influence metabolism, reproduction, mood and tissue function. Hormones are responsible for building new muscle or breaking it down, as well as storing and breaking down fat. Hormones are classified as steroids, peptides and amines, and they all have a different role in the body.

Insulin is a peptide hormone that regulates carbohydrate and fat metabolism, influencing whether foods are used for fuel or stored as fat. Insulin helps reduce the levels of glucose, or sugar, in the blood by promoting the transfer of glucose into the skeletal muscle cells or fat cells. When exercise starts, the sympathetic nervous system prevents the release of insulin, meaning that the consumption of high-sugar foods and drinks can lead to fat storage. Experts recommend waiting to consume any high-sugar drinks, gels or food until after the activity or after the body has begun sweating, if it is an intense or long workout.

Cortisol is a catabolic steroid that supports energy metabolism during long periods of exercise. Cortisol is released when the body experiences too much physical stress from a workout or there hasn't been enough rest to allow for recovery between workouts. This can cause muscle proteins to be broken down, causing muscle loss instead of muscle conservation or growth. Testosterone, on the other hand, is a steroid hormone produced by both men and women that is responsible for muscle repair and growth.

Epinephrine and norepinephrine are amine hormones that support energy production during exercise. Epinephrine is often referred to as adrenaline, that spike in cardiac output that increases heart rate, oxygen to the muscles and blood sugar, which helps fuel the activity. Norepinephrine helps to constrict the blood vessels in the different areas of the body that are not involved in exercise.

Human Growth Hormone, HGH, is an anabolic peptide that supports muscle growth, bone mineralization and fat metabolism. HGH is stimulated by high-intensity training, whether through cardio, weight training or plyometric training. The Insulin Growth Factor, IGF, is a peptide hormone that supports the function of HGH in promoting muscle growth.

Missy Corrigan is executive of community health for Sumter Family YMCA. She can be reached at mcorrigan@ymcasumter.org or (803) 773-1404.