Regular physical activity brings a multitude of benefits encompassing physical, mental, and physiological aspects. A significant benefit category involves the influence exercise has on various hormones within the body, which are critical chemical messengers impacting nearly every function of human physiology:
- Growth Hormone
- Enhances protein synthesis which benefits muscle tone and development, and strengthens bones, tendons, ligaments, and cartilage.
- Reduces glucose utilization while boosting fat burning during physical activity. This shift not only helps in reducing body fat but also stabilizes blood glucose levels, enabling longer exercise durations. Growth hormone secretion from the brain’s pituitary gland escalates with increased duration and intensity of aerobic activities, such as interval training.
- Endorphins
- These natural opioids produced by the pituitary gland help in blocking pain, reducing appetite, inducing euphoria (often referred to as the ‘runner’s high’), and lowering both tension and anxiety.
- Endorphin levels can rise up to five times the resting levels during prolonged, moderate to intense aerobic exercises or during interval training sessions. Regular exercise enhances sensitivity to endorphins, allowing them to remain in the bloodstream longer, thus prolonging the pain-free and euphoric effects post-exercise.
- Testosterone
- Crucial for both males and females, testosterone aids in maintaining muscle mass and strength, elevates basal metabolic rate, reduces body fat, and enhances self-confidence. It is produced by the ovaries in females and the testes in males.
- Although females have significantly lower levels of testosterone compared to males, it still plays a crucial role in female libido and orgasm intensity. Testosterone production starts to wane with age, particularly as women approach menopause and men enter their forties. Exercise boosts testosterone levels in the bloodstream temporarily, beginning about 20 minutes into physical activity.
- Estrogen
- The most biologically active form of estrogen, 17 beta estradiol, intensifies the breakdown of fats from stores for energy, boosts metabolic rate, elevates mood, and enhances libido. While predominantly higher in females, its production decreases as menopause approaches.
- Exercise can increase the secretion of 17 beta estradiol, with elevated blood levels lasting from one to four hours post-exercise.
- Thyroxine (T4)
- Produced by the thyroid gland, Thyroxine accelerates the metabolic rate across almost all body cells. This boost in metabolism increases energy levels and calorie expenditure, playing a key role in weight management.
- Thyroxine levels can surge by about 30% during physical activity, with elevated levels persisting for several hours, especially with increased exercise intensity or duration. Regular physical activity also raises resting thyroxine levels.
- Epinephrine
- Primarily secreted by the adrenal medulla, epinephrine amplifies heart output and directs blood flow to essential areas during exercise.
- It stimulates the breakdown of glycogen in muscles and liver for fuel and enhances fat breakdown for energy. The release of epinephrine correlates with the intensity and duration of the exercise.
- Insulin
- Insulin plays a vital role in lowering blood glucose levels and aiding the transport of glucose, fatty acids, and amino acids into cells. It is secreted by the pancreas in response to rising blood sugar levels, typically after meals.
- Engaging in aerobic exercise causes a decrease in insulin levels starting around 10 minutes into the session and continuing through about 70 minutes of activity. Regular exercise also enhances cellular sensitivity to insulin, improving glucose regulation.
- Glucagon
- Also secreted by the pancreas, glucagon’s primary function is to elevate blood glucose levels when they drop too low. It prompts the liver to convert stored glycogen into glucose for release into the bloodstream and stimulates fat breakdown for energy.
- Glucagon secretion generally starts after 30 minutes of exercise as blood glucose levels begin to decline.
Understanding and harnessing these hormonal responses through regular exercise can significantly aid in managing and reducing body weight, all while enhancing overall well-being.
