by Kirill Micallef-Stafrace
MD MSc Sports Med (Lond.) FFSEM (I)
Sports and Exercise Medicine Specialist

The World Health Organisation has identified mild to moderate Major Depressive Disorder (MDD) as ranking behind Ischaemic Heart Disease for years of life lost due to disability or premature death. Although a number of effective pharmacologic and psychotherapeutic treatments for MDD have been developed, many people do not seek treatment or do not receive adequate treatment. Within this scenario a niche does exist for new treatment approaches that will accommodate the diverse needs and preferences of potential sufferers and yet take into account the limited resources of current healthcare systems. Exercise might be one of these new treatments that can provide a cost effective stratagem and in some cases, maybe even a solution.

In 1999 Lawlor and Hopker reviewed 14 studies that reported the beneficial effects of exercise on MDD and even proposed its effectiveness to be equivalent to cognitive therapy. However, as they rightly pointed out, many of the studies reviewed exhibited flawed research methodologies. Yet this review probably inspired the large number of higher quality investigations that have surfaced in recent years. These studies irrefutably show that subjects suffering from MDD that undertook regular exercise had a greater improvement in their condition than non-exercising control subjects. What is more interesting is that even after exercise was stopped the anti-depressant effect was felt for months after. Thus these newer studies upheld the results of the pre-2000 research, that exercise has a significantly beneficial effect on symptoms of depression. Also, one must not forget the various health benefits a patient can reap if he/she undertakes regular exercise, thereby tackling the co-morbidities commonly found in depressed patients.

Obviously, exercise must be used as an adjunct to conventional therapy and should be undertaken cautiously, especially if the subject is new to exercise or has not exercised for some time. From a health perspective, exercise is ideally practiced most if not all days of the week for a minimum of 30 minutes each time. Aerobic forms of exercise such as running, cycling and swimming, appear to have better results in MDD and if this is the primary reason for referral, health professionals should strive to prescribe these activities.

Health professionals who work with depressed patients know that one of the major stumbling blocks is motivating the subject. This is no different with exercise and thus the chosen exercise must be tailored to the patient and must reflect preferences and accessibility. Some will thrive in individual sports whilst others would require a group exercise setting in order to achieve results.

Whatever the form of exercise chosen, the health professional is integral to the success of the whole scheme. Regular input and encouragement is a must if the therapeutic exercise is to succeed. Familiarisation with the different forms of exercise available to the patients, although not necessary, is a definite bonus. The ability to speak the jargon and communicate in exercise terms with both trainers and patients can break down a number of obstacles before they even appear and smoothen the whole process, thereby increasing the chances of success.

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