The results of regular and focused training can be quite remarkable. Before long, you could be slimmer, fitter and faster. However, there are also many processes occurring inside our bodies when we exercise. Hormones and exercise have a complex but fascinating relationship and health specialist Sarah Schunter is here with the basics.
Training triggers hormones
While your muscles are being used during (and also after) exercise, a bunch of different hormones are released that affect your entire body. Hormones control distinct regulatory and metabolic pathways, necessary for energy production, muscle building and fat reduction. The major hormones involved in exercise are...
Adrenaline and Noradrenaline
These two hormones belong to a group called catecholamines and are produced in the adrenal medulla. Anyone experiencing stressful situations knows exactly how the release of adrenaline feels: once released to the bloodstream, heart rate and blood pressure increase. In their role as stress hormones (triggering “fight or flight” reactions) they provide rapid energy through fat breakdown (lipolysis) as well as the release and biosynthesis of glucose leading to elevated glucose levels in the blood. During exercise, this supplies the muscles with energy.
Cortisol is a major steroid hormone which acts as an activator for catabolic pathways in order to provide high energy compounds e.g. during exercise. Cortisol triggers the production of glucose, acts on fat metabolism by promoting the lipolytic effect of adrenaline as well as noradrenaline and regulates protein turnover (catabolic). Cortisol levels in our blood vary during the day. The highest value is reached in the morning as the body is deprived of energy. However, when getting up we need to be active, meaning we need energy which will be provided by glucose.
Hormones of Happiness
So-called happiness hormones are often produced during exercise: dopamine and serotonin, endorphin and enkephalin and endocannabinoids contribute to the feeling of well-being and euphoria by acting as neurotransmitters in our brain. They are released especially during endurance training; the so-called "runner's high" mainly occurs during long distance runs.
Alongside its function as male sex hormone, testosterone is also responsible for muscle formation, firmer bones and stronger hair. Depending on age, fitness level and workout intensity, testosterone levels increase for between 15 and 60 minutes after training. Testosterone is produced in both sexes, but significantly more so in men (which is why it’s easier for men to develop muscle).
Peptide YY (PYY)
This hormone consists of 36 amino acids and is released from endocrine cells residing in the distal small intestine. The release of PYY is mainly induced postprandial (after eating) by fats. The hormone acts on brain regions that are responsible for appetite and hunger. It means that we’re less hungry after exercise and feel full faster after a meal. Studies have shown that endurance training significantly raises PYY levels.
It’s crucial to have an understanding of which hormone balances you might be influencing with your training program in order to get the most out of your training. The nervous and muscular systems obviously play considerable roles in the outcome of your training, but what’s often ignored is the significance of hormone production.