Exercise as it relates to Disease/Exercise is for the heart and the mind

This is a critique on the article 'Benefits from aerobic exercise in patients with major depression' by Dimeo F (2001). This has been created by u3083570 as an assignment for the University of Canberra.

Background
Physical activity has been reported to reduce the severity of symptoms in patients suffering from depression. This study looked at the short term effects of an aerobic training program on patients with moderate-severe major depression. The prevalence of depression is high throughout life with 1 in 7 Australians experiencing depression within their lifetime. Depression is a disorder which causes feelings of sadness, loss of interest, affecting how one feels, thinks and behaves, leading to a variety of emotional and physical problems. Exercise has been found to increase the level of serotonin within the brain which is involved in regulating mood, libido, sleep and other functions. Difficulties in the serotonin pathway have been linked to depression. Regular exercise may improve the symptoms of depression by:


 * Increasing energy levels
 * A form of distraction
 * Social support/reduction in loneliness if exercising in a group
 * Improving sleep
 * Improving one's sense of control

The current exercise recommendations for Australians by the Department of Health
 * Accumulate 150 to 300 minutes of moderate intensity physical activity or 75 to 150 minutes of vigorous intensity physical activity each week. Or a combination of both moderate and vigorous.
 * Being active in as many ways as possible each day. An example of this includes taking the stairs rather than using a lift.
 * Strengthening activities on at least 2 days each week.

Source of Research
This study was conducted by researchers from the Department of Sports Medicine in Germany and was approved by the Institutional Ethics Committee. The article was published in the British Journal of Sports Medicine in 2001.

Research Type
The study conducted in this article is a pilot study. This article detailed the purpose of conducting this pilot study; to examine the effects of a short term aerobic training programme on patients with major depression. The data was collected by looking at the changes in depression scores pre and post completing the training program, via the Hamilton Rating Scale for Depression (HAMD) and the scale for self assessment of Depression (D-S). Data which was obtained before and after the training program were included in the statistical analysis. Depression scores were compared by the two tailed Wilcoxon test and the correlation between subjective and objective improvement in depression were evaluated by the Spearman rank correlation test.

Research Involved
The study consisted of 12 patients, consisting of 5 men and 7 women, ranging between 28–64 years of age. The patients were recruited from either being an inpatient or an outpatient with major depression. According to the Diagnostic and Statistical Manual of the American Society and Psychiatry (DSM IV) criteria all patients had been diagnosed as suffering from major depressive disorder. Patients completed a training program which consisted of walking on a treadmill for 30 minutes over a 10 day period. The program was only carried out for 10 days which I do not believe is a significant length of time to see true results. Other studies conducted within this field have looked at 12–16 weeks of training. At the end of the 10 days, the researchers observed a significant improvement in 6 of the patients, a slight improvement in 2 and 4 patients had unchanged severity of symptoms.

Important Findings
At the end of the exercise program the researchers found a clinically and statistically significant reduction in depression scores. The HAMD before 19.5 (3.3) and after 13 (5.5), producing a p value = 0.002. Self-assessed intensity of symptoms (D-S) before, 23.2 (7) and after, 17.7(8.1) producing a p value = 0.006. The researchers also found that subjective and objective changes in depression scores correlated strongly (r = 0.66, p = 0.01). Five patients had scores of 10 or less on the HAMD. The response to therapeutic intervention had been defined as a reduction of 50% or more or a final score in the HAMD of 10 or less. Six of the patients at the end of the study asked to continue the aerobic exercise program.

Conclusions
The study found that aerobic exercise can produce a substantial improvement in mood in patients with major depressive disorders within a short period of time. I believe that the findings from this study and studies completed since, should be taken into serious consideration. Depression affects 1 in 7 Australians throughout life and if there is a way to treat this that does not involve taking medication and will also prevent other diseases from occurring as exercising regularly helps one to stay healthy, then this topic needs to be researched more. A study completed in 2006 by Knubben et al, found similar results to Dimeo F (2001) with a substantial improvement in mood in a short period of time. In 1999 Blumenthal et al, looked at the response of exercise, drugs or the combination of both. In this study they found that antidepressants facilitated a quicker therapeutic response then exercise. The exercise protocol that they undertook, only exercising 3 times a week and at a lower intensity than the participants of Dimeo F (2001) and Knubben et al (2006), suggests that patients are required to reach a certain intensity of exercise to achieve a reduction in depression scores that is considered clinically significant in a short period of time. Blumenthal et al completed a study in 2007 which found that both exercise and medication treatment are both better than no treatment at all.

Practical Advice
The results from this study are clinically relevant, with the participants being comparable to the general population suffering from severe depression. Antidepressants which have been shown to relieve symptoms of depression have a latency period of several weeks until an effect can be seen. During this latency period patients as well as physicians are left with a lack in therapeutic treatment options. Therefore there is a need for a treatment which reduces symptoms within s short period of time. The benefits in this study were seen within a short period of time which is of significance. Therefore, patients may benefit from an exercise program while waiting for the medication to take effect or as an alternative to taking medications to avoid the side effects of antidepressants. The limitations to this study, small sample size and lack of control group, are acknowledged by the authors with future studies planned to further explore and rigorously test the effects of aerobic exercise programs and improved depression scores.

Further Information/Resources

 * Facts on Depression http://www.blackdoginstitute.org.au/factsheets/
 * Facts on Exercise and Depression http://www.blackdoginstitute.org.au/docs/ExerciseandDepression.pdf