Neurotransmitters and Prolonged Exercise
Written by: Kevin Cann
We live in an age where sleep is a luxury, chemicals fill our air, and processed foods make up the majority of our supermarkets. To attempt to stay healthy and de-stress, we may go for a run, or sign up for a membership at our local gym. The lack of sleep and poor food choices may have made us get a little soft around the midsection, and instead of fixing those issues a lot of us decide we need to workout harder or run longer. What we fail to understand is that this could be devastating to our physical and emotional health.
When we decide to make these decisions, we are wreaking havoc on our biochemical balance in our brains. Serotonin and dopamine are two neurotransmitters that are responsible for our mood and energy. We need enough of them floating around to elicit a response, and they also must be in balance with one another for us to feel good. With our current lifestyles and living conditions, we compromise this balance, and this compromises our emotional and physical health.
Poor diet, lack of sunlight, stress, and caffeine consumption can all affect the abundance of these neurotransmitters. What a lot of people do not know is that prolonged exercise also affects these neurotransmitters. Studies showed that exercise caused an increase of serotonin precursors, as well as dopamine, in the brainstem and the hypothalamus. These researchers stated that it is possible that the changes in the neurotransmitters could affect both physical and mental fatigue as well as mood (Blomstrand, 1989).
The central fatigue hypothesis was a theory developed to explain the fatigue associated with prolonged exercise. Originally it stated that fatigue was associated with increased amounts of serotonin in the brain. That hypothesis has now been changed to state that it is related to increased amounts of serotonin in the brain in relation to dopamine (Meeuessen, 2006). These studies are important to understand for a couple of reasons.
For one, if we have decreased amounts of dopamine, or there is not the proper balance between serotonin and dopamine, exercise will be a difficult task. We will fatigue quickly and it will not be a pleasant experience. Also, if we decide to keep increasing exercise due to failure to reach goals, we can eventually burnout our ability to make these neurotransmitters, leaving us deficient in them. This is where negative mood changes can occur.
Another issue comes in terms of our hunger response. An increase in physical activity will drive us to increase our caloric intake to balance off the energy lost. Kenneth Blum developed the Reward Deficiency Syndrome for addiction, and stated that he believes that glucose cravings and obesity are due to a lack of dopamine receptors in the brain (http://robbwolf.com/2012/09/14/12377/). Not only may our moods and energy levels be affected, but an increase in food cravings can occur as well.
Exercise that fits our lifestyles is an important factor to overall health. If we lack sleep, are stressed, vitamin D deficient, etc. it may be a good idea to not exercise too strenuously. Also, we need to manage our stress, get some sleep, and eat a diet rich in amino acids and nutrients to give us the tools to build our feel good neurotransmitters. There are times when we need some extra support to get through stressful situations and finding the appropriate healthcare practitioner can help.