The Effects of Physical Fitness on Depression

Depression disorders constitute one of the major health issues of our time. Depression is ranked fourth in Disability Adjusted Life Years (DALYs) according to the World Health Organization (WHO), a figure which is expected to grow over the coming years to reach second place by the year 2030 1. Depression is a disorder, which if untreated can increase the risk of suicide. According to the WHO suicide occurs in close to one million cases every year making it one of the 20 most common causes of death2.

Researchers are discovering more natural ways of reducing the symptoms of depression. The following study examined older patients with clinical depression and tested the effects of physical exercise on their depressive state. Volunteers were of age 50+, underwent an initial screening, and were analyzed by a trained clinical psychologist, who determined the level of severity of the depression using the 17- item Hamilton Rating Scale for Depression (HAM-D).

The volunteers qualified for the study only if they met the four following symptoms of clinical depression (MMD): sleep disturbance, weight loss or loss in appetite, psychomotor retardation, and feeling of worthlessness or excessive guilt impaired cognition or concentration and recurrent thoughts of death. The selected participants scored at least 13 on the HAM-D testing. The group of subjects was narrowed down to 156 older men and women. After the baseline assessment each volunteer was placed into one of three groups: exercise, medication, or combination of both.

None of the participants were taking medication prior to this study. Randomized procedure was used to ensure that a even amount of each level of depression was put into each group. The treatment started one week after the diagnostic review. The participants in the study were given a schedule that consisted of three supervised exercise sessions per week for 16 weeks. Volunteers were given individual customized training ranges equal to 70% to 85% of the heart rate reserve calculated from the persons maximum heart rate reached in an earlier treadmill test on each subject.

The workout sessions consisted of 30 minutes of continuous walking or jogging at the intensity that would maintain the heart rate within the assigned range. Each session would start with ten minutes of warm up exercises and conclude with five minutes of cool down exercises. Each participant’s workout monitored and recorded radial impulses by a trained exercise physiologist. The results of each group were not what the researchers expected. The group who took medication showed the fastest improvement with less symptoms of depression.

Yet, among those who did the combination of medication and exercise with more severe levels of depression show the fastest improvement. While medication may help older patients show quicker improvement in lowering depression symptoms. The combination of therapies that include exercise is equally effective over a longer period of time. Exercise might be beneficial because patients are actually taking an active role in trying to recover. Simply taking a pill everyday is very passive.

Patients who exercise may feel a greater sense of ownership over their condition and gain a greater sense of accomplishment. One might be more self-confident and have a greater self-esteem because they are able to do it themselves, and are able to attribute their improvement to their own ability to exercise. While we don’t know exactly why exercise confers such a benefit, this study shows that exercise should be considered as a credible form of treatment for these patients.

Almost one-third of depressed patients in general do not respond to antidepressant medications, and for others, the antidepressants can cause unwanted side effects. Physical exercise can be an effective treatment against depression. 1 Mathers CD, Loncar D,”Projections of global mortality and burden of disease from 2002 to 2030”. PLoS Med, 2006. 2Kringlen E, Torgersen S, Cramer V. A “Norwegian psychiatric epidemiological study” . Am J Psychiatry 2001