Exercise is a familiar phenomenon when it comes to living a healthy lifestyle. The general population understands the idea of exercising for 30 minutes per day along with eating healthy is recommended in order to live a healthy life. Much research and publicity have been put into the benefits of exercise. Some of the well-known benefits include, but are not limited to, mood improvement, an increase in energy, prevention of health problems, as well as memory improvement. With anxiety, exercise has been shown to reduce the perception of stress, be a coping mechanism, and improve mental health in general. Exercise is divided into three categories; aerobic, anaerobic, and flexibility. Each category is further divided into mild, moderate, and intense levels.
Some of the ways stress affect the brain is understood. Stress induces a high concentration of corticosterone hormone in order to decrease inflammation within immune cells in the brain. Within anxiety, however, resistance to corticosterone hormone can be seen within the immune cells in the brain resulting in a need for an even higher concentration in order for a decrease in inflammation. However, there are categories of exercise which have been shown to have different effects within human and animal studies on anxiety.
Mild/Moderate exercise counteracts stress behaviors by changing neural activity, however, the mechanism is not understood yet. This would include exercise like walking, jogging, swimming, lifting, etc. for a shorter period of time than intense exercise. Post-Traumatic Stress Disorder (PTSD) has been linked to reduced hippocampal volume whereas regular exercise has the opposing effect by increasing cognition, working memory, hippocampal neurogenesis, and an increase in BDNF. Military veterans suffering from PTSD show that the majority also have anxiety and/or depression. A barrier PTSD veterans face for treatment is the stigma, access, and cost for treatment, but an alternative treatment a study completed with veterans suggest exercise as a management option. Within nonveteran patients with PTSD, exercise was also shown to alleviate the symptoms of the disorders, including anxiety and depression.
Intense and/or forced exercise has been shown to have the adverse effect by increasing the stress level within animal studies. Chronic stress is reported to suppress neurogenesis and negatively impact hippocampal function. Stress may lead to stem cells being differentiated into astrocytes rather than neurons within the dentate gyrus of the hippocampus. Therefore, the rate of new neurons decreases. Intense exercise is defined as above lactate threshold. Lactate has shown a critical role in long-term memory by being involved in growth-factor signalings, such as BDNF, and expression of genes. Studies done with mice show exercise above the LT and exercise forced by shocks resulted in higher stress shown by an increase in corticosterone and adrenocorticotropic hormone concentration and produced lower results for hippocampal neurogenesis in mice. Stress from exercise indicates that exercise benefits have a lessened effect on the management of anxiety. Therefore, intense and/or forced exercise can be shown to lower hippocampal neurogenesis and not help in the management of anxiety through the stress that is caused by an intense and forced type of exercise.
Exercise’s Influence on Anxiety
