People who exercise have better mental fitness, and a new imaging study from UC Davis Health System shows why. Intense exercise increases levels of two common neurotransmitters — glutamate and gamma-aminobutyric acid, or GABA — that are responsible for chemical messaging within the brain.
Published in this week’s issue of The Journal of Neuroscience, the finding offers new insights into brain metabolism and why exercise could become an important part of treating depression and other neuropsychiatric disorders linked with deficiencies in neurotransmitters, which drive communications between the brain cells that regulate physical and emotional health.
“Major depressive disorder is often characterized by depleted glutamate and GABA, which return to normal when mental health is restored,” said study lead author Richard Maddock, professor in the Department of Psychiatry and Behavioral Sciences. “Our study shows that exercise activates the metabolic pathway that replenishes these neurotransmitters.”
The research also helps solve a persistent question about the brain, an energy-intensive organ that consumes a lot of fuel in the form of glucose and other carbohydrates during exercise. What does it do with that extra fuel?
“From a metabolic standpoint, vigorous exercise is the most demanding activity the brain encounters, much more intense than calculus or chess, but nobody knows what happens with all that energy,” Maddock said. “Apparently, one of the things it’s doing is making more neurotransmitters.”
The striking change in how the brain uses fuel during exercise has largely been overlooked in brain health research. While the new findings account for a small part of the brain’s energy consumption during exercise, they are an important step toward understanding the complexity of brain metabolism. The research also hints at the negative impact sedentary lifestyles might have on brain function, along with the role the brain might play in athletic endurance.
“It is not clear what causes people to ‘hit the wall’ or get suddenly fatigued when exercising,” Maddock said. “We often think of this point in terms of muscles being depleted of oxygen and energy molecules. But part of it may be that the brain has reached its limit.”
To understand how exercise affects the brain, the team studied 38 healthy volunteers. Participants exercised on a stationary bicycle, reaching around 85 percent of their predicted maximum heart rate. To measure glutamate and GABA, the researchers conducted a series of imaging studies using a powerful 3-tesla MRI to detect nuclear magnetic resonance spectra, which can identify several compounds based on the magnetic behavior of hydrogen atoms in molecules.
The researchers measured GABA and glutamate levels in two different parts of the brain immediately before and after three vigorous exercise sessions lasting between eight and 20 minutes, and made similar measurements for a control group that did not exercise. Glutamate or GABA levels increased in the participants who exercised, but not among the non-exercisers. Significant increases were found in the visual cortex, which processes visual information, and the anterior cingulate cortex, which helps regulate heart rate, some cognitive functions and emotion. While these gains trailed off over time, there was some evidence of longer-lasting effects.
“There was a correlation between the resting levels of glutamate in the brain and how much people exercised during the preceding week,” Maddock said. “It’s preliminary information, but it’s very encouraging.”
These findings point to the possibility that exercise could be used as an alternative therapy for depression. This could be especially important for patients under age 25, who sometimes have more side effects from selective serotonin reuptake inhibitors (SSRIs), anti-depressant medications that adjust neurotransmitter levels.
For follow-up studies, Maddock and the team hope to test whether a less-intense activity, such as walking, offers similar brain benefits. They would also like to use their exercise-plus-imaging method on a study of patients with depression to determine the types of exercise that offer the greatest benefit.
“We are offering another view on why regular physical activity may be important to prevent or treat depression,” Maddock said. “Not every depressed person who exercises will improve, but many will. It’s possible that we can help identify the patients who would most benefit from an exercise prescription.”
So we all know that feeling that we get after exercise – we feel generally happier, less stressed, less anxious and also sleep better. Exercise produces a rush of happy hormones we also know as endorphins. So what are these endorphins and why do they make us feel happy?
Endorphins are chemicals that are produced in our brains in response to stress or pain. Running, doing a hard workout, playing a sport or any exercise at all that increases our bodies stress response has the ability to make our brains release endorphins. The endorphins have the ability to travel through our neural networks as a neurotransmitter. One thing we do know about endorphins is that they make us feel really good. So how does this work then?
A part of the brain called the hypothalamus sends a signal to increase endorphin uptake through our bodies neural network when we subject ourselves to certain activities like exercise, sex, eat certain foods or experience pain. The endorphins then attach themselves to specific receptor sites within our neural network – these are called opioid receptors. These special receptors have the ability to block out pain signals and also to increase that euphoric happy feeling we get after we exercise. It is the same receptors that are locked onto when we take pain relief in the form of opiates.
Once we achieve a positive result in something we do, either though through exercise or simple activities like sticking to a plan you’ve made, your brain will also release another happy hormone called dopamine. Dopamine is responsible for us feeling addicted to pleasure seeking behaviors. By setting regular and achievable exercise goals that you reach it is highly possible to make exercise the trigger for your brain to release dopamine.
Serotonin is another one of our brains happy hormones that act as a natural anti-depressant. When we exercise serotonin levels in our brain increase and so does your level of happiness.
I know all these terms may seem confusing but there is another very important happy hormone called oxytocin. Oxytocin is released when we feel loved, cared for and connected to others. Your brain will also release oxytocin when you are kind to others.
So no matter how hard it may seem to get yourself moving on some days, putting one foot in front of the other and pushing yourself to move and exercise is not only good for your muscles and joints but also stimulates your brain. You’ll produce your very own happy hormones, reduces your stress levels and have you wanting to repeat it all over again next time. Give your fellow team mates, friends and family an encouraging kind words regularly as well- it will not only help them feel happy but will increase your happiness as well.
Feeling dizzy? You Could Have a Vestibular Disorder
Do you experience dizziness? Perhaps when rolling into or over in bed, or turning your head to one side?
Dizziness can be more than dehydration, a big night out, or a compulsion to spin in circles on your office chair. It can be a symptom of asymmetry in your body’s sensory systems.
The most common condition that causes dizziness is benign paroxysmal positional vertigo, or BPPV. The brain has three main mechanisms for perceiving how we interact with the environment around us. These are the visual, proprioceptive, and vestibular systems.
The visual system is self-explanatory. The proprioceptive system is a network of nerves in all of your muscles and joints that relay information about the position of those muscles and joints back to the brain. It is how you can close your eyes and still accurately position your arms and legs in different poses.
The vestibular system is located in your inner ear and is used to identify the position and movement of the head in space. This is the system commonly linked to dizziness and vertigo.
The vestibular system is made up of three perpendicular fluid filled canals in each ear, which relate roughly to the planes of movement.
These canals each have sensory nerves at one end that are made up of crystals resting on fine hairs. When you turn your head, the fluid moves through the canals and pushes on the crystals. This causes the hairs to move and stimulates the nerves.
Your response in each ear should be equal and opposite, and work in tandem with your visual and proprioceptive systems. If things are not working in tandem, then dizziness, vertigo (room spinning), or nausea may result.
Have you ever felt nauseated in a car, or on a boat? This is because your vestibular system recognises that your head is moving but according to your eyes, you are still or moving a different way.
Someone may have suggested looking out the window or finding the horizon. This is great advice as fixating on something which the car or boat is moving relative to, provides a visual reference point and reduces or eliminates the disagreement between the visual and vestibular system.
In patients suffering BPPV, a similar disagreement occurs but it is completely internal. It occurs when crystals in one ear canal become dislodged from the hairs and drift down into the canal. This can happen as a result of trauma but is just as frequently unrelated to any incident.
When the head is turned, the nerve stimulation in one ear is different to the other and a combination of dizziness, vertigo, and nausea can result.
Generally, this resolves in seconds, or in more severe cases last up to two minutes. Usually only one canal will be affected at a time so symptoms are commonly worse to one side, and occur most severely in a single plane of movement.
If you are dizzy due to asymmetry, then your physiotherapist can assess and treat it. Assessment of specific movements can isolate which ear and which canal is causing the problem and treatment involves techniques designed to use gravity and inertia to relocate the crystals back to where they belong at the end of the canal.
NOTE: If you are suffering from severe, sudden onset headache, or persistent dizziness, double vision or nausea that seem unrelated to any particular movement then consult a medical doctor immediately.
At first it was just a niggle in your knee when you climbed stairs or were squatting. Then the pain and stiffness became more than a niggle and you began to feel it when walking, sitting and resting.
You may be hearing popping or cracking sounds in your knee, and notice that your knee “gives out” every now and again.
The knee is an amazing but complicated joint and knee pain is one of the most common reasons that people visit a physiotherapist.
Pain behind the kneecap is commonly called runner’s knee because it is often seen in athletes and people with an active lifestyle, although it can also be seen in everyone from the young adolescents during growth spurts to elderly people.
The medical term is patellofemoral pain syndrome. It is pain behind the kneecap where your patella (kneecap) slides along the groove in your femur (thighbone) beneath.
Pain and stiffness occurs when the kneecap does not slide smoothly and misaligns causing it to rub against your femur. Repeated mis-tracking causes pain, stiffness, and ultimately can cause damage to your kneecap joint surface.
Knee pain is most commonly noticed during activities that involve knee bending, jarring or weight bearing.
People most at risk are those whose sport or activity includes running, jumping or the need to land in a squatting position. Sports most commonly associated with knee pain include running, netball, volleyball, basketball, tennis, skiing and cycling. Many tradies such as tilers and carpet layers also have problems.
Causes of Runner’s Knee
Overuse – increased activity or increased duration and intensity of the activity
Changes in footwear or playing surfaces
Tight outer thigh muscles and weaker inner thigh muscles causing the kneecap to be pulled to one side
A twisting injury
Flat feet and lack of arch support
Weak hip control muscles
First aid for Runner’s Knee
Generally, knee pain is gradual onset, which means it gradually increases in severity over time.
As with most injuries, the best initial first aid is rest, ice packs (15 minutes at a time every 2-3 hours), and taking anti-inflammatory painkillers such as ibuprofen.
You do not need a referral from a doctor to see a physiotherapist. If the pain is moderate, then you can seek treatment with your Physiotherapist immediately.
Physiotherapy is a proven treatment for runner’s knee. Your physiotherapist may initially tape or strap your kneecap to help pull it back into alignment and reduce pain.
Massage and joint mobilisation techniques are also commonly used to reduce swelling and restore movement.
You will be prescribed exercises to stretch and strengthen muscles that may be contributing to the problem. These exercises will change as you heal and will gradually increase in intensity to match your recovery.
If you wish to continue exercising to maintain your fitness during your treatment, then explore swimming, deep-water running and low-impact gym equipment such as elliptical trainers.
Depending on your knee pain cause, you may also be advised to explore arch supports, orthotics or different footwear. You may also require postural or technique correction in your chosen sport to stop problems from recurring, as well as a strength and conditioning plan to get you back to full competitive fitness.
In our experience, over 90% of runner’s knee physiotherapy clients will be pain free within six weeks of starting treatment. However, for severely damaged joints or arthritic joints, surgery may be required.
Things to Remember
Runner’s knee or patellofemoral pain syndrome is a common cause of knee pain.
It is a gradual onset injury and is most commonly noticed during activities that involve knee bending, jarring or weight bearing.
Physiotherapy is a proven method to speed healing, and prevent recurrence of knee pain.
Future management may also involve assessment of your gait and posture during exercise, and prescription of arch support or custom made orthotics.