Physical exercise has proven to be an effective supplement in preventing and treating depression . Among other effects, physical exercise stimulates the production of proteins that repair neurons and increase their proliferation, regulates the levels of serotonin and other neurotransmitters , increases cerebral blood flow and stimulates the release of endorphins.
Depression, a very common evil
It is estimated that one in six women and one in ten men suffers or will suffer from depression in their lifetime. Today 350 million people suffer from it, possibly an underestimated figure given that depression is considered taboo in many societies today.
We are all familiar with depression due to its high prevalence. However, its diagnosis should always be made by a specialist to avoid confusion with other disorders such as anxiety, grief, sadness or simply apathy. The reality is that a depressed person is sad, is not able to enjoy, has low self-esteem, feelings of guilt, shows fatigue and lack of concentration. As depression increases in severity it can trigger sleep or appetite disorders and, in the worst cases, suicide.
Treatments for depression
The treatment of depressive disorders is effective and is mainly based on two approaches: dialogue with a therapist or psychological therapy (cognitive-behavioral or psychotherapy) in mild and moderate cases; and antidepressant drugs ( serotonin reuptake inhibitors and other neurotransmitters and tricyclic antidepressants ) for moderate and severe depression. Although it depends on each person, drug treatment is not without adverse effects including nausea, headache, dry mouth, insomnia, sexual dysfunction and sedation.
Despite the efficacy of these interventions, it is estimated that more than half of those affected worldwide are not treated. In addition, taking into account its high prevalence and the adverse effects of some antidepressant drugs, it is vital to use complementary tools to psychological and pharmacological treatment that help prevent and treat this disease and its dire consequences for those who suffer from it.
But … what other intervention, besides antidepressants and psychotherapy , prevents and helps treat depression ?
Physical exercise. Numerous prevention-oriented scientific studies have shown that physical exercise reduces the risk of depression. Additionally, research suggests a dose-response; that is, the more physical exercise is practiced (more than five hours per week), the lower the probability of suffering from this disorder. However, if you already suffer from depression , you still have time to benefit from the therapeutic effects of physical exercise . Exercise has an effect similar to that of psychological therapy and some antidepressants, reducing the symptoms of depression. Furthermore, the evidence underscores that aerobic exercise (running, swimming, cycling, etc.) induces greater benefits than strength-based exercise.
Even knowing these benefits, it is not easy to get the depressed person to start a routine physical exercise program. In psychiatry consultation we usually find poorly motivated patients. However, by reinforcing the bond and trust in the professional, highly effective involvement and adherence to training can be achieved.
How can physical exercise prevent and improve the symptoms of depression?
The repeated muscle contractions produced during physical exercise produce signals that affect all organs and systems, including the brain. The changes produced in the brain during physical exercise counteract the neuronal disturbances that cause depression.
While we do physical exercise, our muscles release a multitude of chemical substances into the blood that affect our neurons, making them able to repair, proliferate, improve their functionality and increase their connections (neuroplasticity). They are the so-called neurotrophic factors. Precisely, some antidepressant drugs mediate their action by increasing the brain levels of these factors, an effect produced naturally when doing physical exercise.
The proliferation of neurons (neurogenesis) occurs in the hippocampus, a region especially affected in disorders such as depression and Alzheimer’s. In addition, endogenous opioids (the famous endorphins) and endocannabinoids are released, which modulate the brain to produce an anxiolytic, analgesic and a feeling of happiness.
Depressed people have altered neurotransmitters such as norepinephrine, dopamine and serotonin, factors that mediate our mood (hence one of the most widely used drugs are serotonin reuptake inhibitors). At the blood and brain level, exercise increases serotonin levels, thus reversing its alteration in patients with depression.
When a person is trained they do not need to be exercising for their brain to benefit. Physically active people have better brain irrigation that helps them oxygenate their neurons and eliminate the waste that they produce naturally. In addition, they show less inflammation, a greater antioxidant capacity and a better metabolism, all of them targets in antidepressant treatment .
In summary, while we do physical exercise , an infinity of signals are modulated that counteract the metabolic and neuronal alterations that occur in depression , preventing its appearance or assisting in its treatment. Thus, given that the classic treatments have certain limitations, we can consider physical exercise as a powerful complementary tool that, in the short and long term, will provide us with mental health.
Helios Pareja , researcher and professor at the European University and the Hospital 12 de Octubre Research Institute; and Sara Mayero , professor at the European University and psychiatrist at Moncloa University Hospital (ASISA).
