It’s no good moaning about hormones – we all have them after all!
The endocrine system has a wide variety of functions from regulating metabolism to opening up (dilating) airways. It uses chemical messengers called hormones which play a vital role in maintaining the balance within our bodies – a condition called homeostasis. In this article we’ll explore the major endocrine organs, some of the hormones they produce and the functions of these specialised chemicals…
Endocrine organs:-
1) Thyroid gland – situated in the front of the throat and shaped like a butterfly, the thyroid gland secretes thyroxin which is responsible for regulating metabolism and body temperature. To function properly, the thyroid gland requires iodine (which we get from our diet) but in some people the thyroid gland can become dysfunctional which may result in an underactive thyroid or “hypothyroidism” (hypo = low). Low levels of thyroxin can lead to lowered energy levels, increased sensitivity to cold or unexplained weight gain. Hypothyroidism is usually diagnosed by blood test and can be treated with thyroid medication.
2) Adrenal glands – located on the top of the kidneys, the adrenals produce adrenaline which is responsible for initiating the” fight or flight” response associated with stress. Adrenalin speeds up the heart rate, dilates blood vessels, increases blood glucose levels and prepares the body for activity. Adrenalin is essential – too little adrenaline may result in lacklustre physical performance, poor concentration and lowered motivation But excessively elevated levels of adrenaline can causes problems too such as nervousness, irritability and impaired fine coordination (shaky hands!). Prolonged and excessively high levels of adrenalin can result in stress related diseases such as CHD, diabetes and hypertension (high blood pressure) so it’s important to try and manage stress (and therefore adrenalin) levels. The adrenals also produce cortisol which responsible for the regulation of protein, carbohydrate and fat metabolism. Like adrenalin, it is normally produced when we are stressed either physically or emotionally. It is deemed to be a “catabolic” hormone meaning it breaks things down. Whilst cortisol is essential for maintaining homeostasis, however by promoting protein breakdown and inhibiting protein synthesis, recovery from exercise can be impeded. As cortisol is linked to too much stress it’s best to keep levels to a minimum to maximise results from your training!
3) Pancreas – a flat gland located in the abdomen, the pancreas has many functions but we’ll focus on its involvement with regulation of blood glucose levels. When blood glucose levels begin to rise e.g. after eating carbohydrates, the pancreas produces the hormone insulin. Insulin works to keep blood glucose levels from rising excessively by promoting the uptake of glucose into cells to be stored as glycogen, inhibiting the burning of fat so that glucose can be used as fuel and converting excess glucose into fat for storage for use later. Insulin is essential for carbohydrate metabolism but excessively high levels or prolonged elevation (e.g. caused by a high sugar diet) is strongly linked to diseases like obesity, type II diabetes and CHD. Should blood glucose levels begin to drop too low e.g. after strenuous exercise, missing breakfast or a low calorie/carb diet, the pancreas will release another hormone called glucagon. Glucagon causes the release of glycogen (stored glucose) from the liver and the breakdown of muscles so they can be used for fuel. Like cortisol, glucagon is deemed a catabolic hormone and as such, its presence will impair the recovery from exercise so it’s important to maintain blood glucose levels within normal range to minimise its impact.
4) Testes/ovaries – the male and female gonads are responsible for the production of testosterone, the major anabolic hormone. Testosterone is also the main hormone responsible for development of the secondary male sex characteristics e.g. body hair, facial hair and muscle mass as well as protein synthesis which is essential for the development of the muscular system. Men have around ten times the amount of testosterone than women and as a result are much more able to develop larger muscles (in a process called hypertrophy). Testosterone levels can be optimised in both sexes by engaging in regular resistance exercise, eating a diet rich in fruit, vegetables and essential fats, consuming adequate zinc and magnesium and avoiding too much stress.
To keep your endocrine system the hormones it produces working properly it’s important to consider the following…
- Keep blood glucose levels stable by eating both pre and post exercise meals which contain carbohydrates and avoiding too much refined carbohydrate in the diet
- Keep stress levels to a minimum except when trying to get “psyched up” to train or compete. Make sure relaxation and recovery periods are included in weekly training plans.
- Eat well, consuming a varied diet containing plenty of the essential nutrients required so that endocrine organs can work properly. Very low calorie and very low fat diets have been linked to disruption of testosterone and oestrogen production, as has over training so avoid these practices to maximise testosterone production.
Popularity: 3% [?]
