Regular exercise reduces anxiety. This much we have known for decades. But how?
First there’s a few definitions we need to know.
Amino acids, often referred to as the building blocks of proteins, are compounds that play many critical roles in your body. They’re needed for vital processes like the building of proteins and synthesis of hormones and neurotransmitters.
Serotonin or 5-hydroxytryptamine is a neurotransmitter (Chemical used to pass messages between nerve cells.) It is thought to be active in constricting smooth muscles, and it contributes to wellbeing and the feeling of happiness, among other things.
Tryptophan is an essential amino acid found in foods like turkey, chicken, fish and eggs.
After absorbing L-tryptophan from food, our bodies convert it to 5-HTP (5-hyrdoxytryptophan), and then to serotonin, melatonin, and vitamin B6 (nicotinamide)
Endorphins are neurotransmitters produced in the pituitary gland, your spinal cord and throughout other parts of your brain and nervous system. They interact mainly with receptors in cells found in regions of the brain responsible for blocking pain and controlling emotion.
Cortisol is a steroid hormone that is produced by the adrenal glands. When released into the bloodstream, cortisol can act on many different parts of the body. It can help your body respond to stress or danger & increase your body’s metabolism of glucose.
The amino acid and tryptophan effects
Exercise causes branch chain amino acids to be taken to the muscles. It is believed that this increase in amino acids arriving in the muscles allows more tryptophan to head to the brain. More tryptophan in the brain means more serotonin. More serotonin means more happiness 🙂
We have all heard of the runners high. A feeling of euphoria experienced during/after a good run. We experience the same feeling after an intense workout.
When we exercise, we put our bodies in a state of stress and pain. Endorphins are released as our bodies natural pain killer. With a morphine like high, we feel less pain and increased happiness. Endorphins also have a sedative effect improving sleep regularity for habitual exercisers.
The cortisol response
Cortisol is released as a response to threat. This lowers non-essential bodily functions that could prevent the effectiveness of the fight or flight response (e.g. digestion, growth, and reproduction)
This increase in cortisol has some positive effects on the body if you are in a situation that requires evasive manoeuvres. It increases blood sugar so you’ve got energy to burn. It increases memory and attention (Optimising cognitive ability is essential if you’re preparing to fight for your life). And it decreases sensitivity to pain, also essential if your about to fight.
But it does have some negative effects. Suppressed immune function and decreased serotonin to name a few.
In a normal threat situation these cortisol effects are all good. The positive effects increase your survivability and the negative effects subside as soon as the threat is gone. Making way for the happy, i’m alive, feeling post fight or flight.
But what happens if the threat is not real. This is often the case with veterans who have returned from a war zone where they are required to be alert and searching for threat 24/7. They get home and remain hyper-alert even though the threat is gone.
The body will release cortisol in preparation for fight or flight. But because the threat is not real, there is no cut off point. No, I’m safe, moment. This can lead to prolonged or repeat exposure to excess cortisol.
Long term or repeat exposure to cortisol can cause other chronic issues with your body. Anxiety, depression, loss of sleep and weight gain to name a few. These issues create a vicious cycle. Eg, Cortisol causes anxiety. Anxiety causes increased perception of irrational threat perception. Irrational threat perception releases cortisol and causes anxiety. The beginning of the downward spiral.
So how do we curb our chronic exposure to cortisol?
Anthropologically speaking, when we exercise we are simulating a fight or flight activity. We are training our body to be stronger, faster, bigger, in order to be better at fighting or running away. As such, when we exercise, our body goes through the cortisol release cycle. Increasing cortisol levels while training, then reducing cortisol levels when we are finished.
Setting your workout to simulate a fight for your life, or a sprint for your life, is the best method to teach your body the natural cortisol cycle.
This is simulated best with HIIT (high intensity interval training). During a HIIT workout, you are pushing yourself as hard as possible for a short period of time, then rest. Your average workout should be between 20-40 minutes. Ideally you will push yourself to the point of, I’m going to die, in under 20 minutes, then you are done.
This takes your body through the full cycle – Im in danger, release cortisol, fight for my life (The workout), then i’m safe (The workout is over). While your cortisol levels are high during your workout, the completion of your workout will see your cortisol reduced to normal levels.
For people suffering from anxiety, depression or experiencing states of hyper-alertness, exercise is a great tool for reducing cortisol levels and paving the way to recovery. Combined with good diet, regular sleep patterns and meditation, regular exercise is the perfect, drug free, mental health improver.
Caveat – Extended endurance training, while it does have its place and benefits, can have the opposite effect. It puts your body in a prolonged state of stress with high cortisol levels and will not trigger the complete cortisol cycle.