This structured review aims to determine the effectiveness of low impact physical exercise in improving mood in adults with mild to moderate depression. To achieve this aim, four objectives will be met: (1) identification of all eligible randomised controlled trials which assess the effects of low impact physical exercise and other therapies or no therapy on mild to moderate depression, through systematic database searches, (2) synthesis of the outcomes of these trials to determine the effectiveness of low impact physical exercise in improving mood in adults with mild to moderate depression, (3) analysis of the outcomes of these trials to establish the frequency and intensity of low impact physical activity required for there to be clinically relevant and / or statistically significant effects on mood in adults with mild to moderate depression, and (4) use of the findings of this review to develop recommendations for clinical practice. Randomised controlled trials have been selected as a focus for this review because they are recognised as high-quality evidence and, as they enable the quantification of effect, are well-suited to addressing the research topic. Randomised controlled trials will be identified through systematic database searches, screened for eligibility against a set of well-defined criteria, assessed for quality and subjected to data extraction. Results will be synthesised using statistical processes, and recommendations for practice developed and disseminated.
The term ‘depression’ describes a diverse range of mental illnesses characterised by “the absence of a positive affect … low mood and a range of associated emotional, cognitive, physical and behavioural symptoms” (British Psychological Society & Royal College of Psychiatrists, 2010: p. 17). The aetiology of depression is poorly understood, however it is believed to have a complex biochemical and neurophysiological basis (British Psychological Society & Royal College of Psychiatrists, 2010). Depression – and particularly mild to moderate depression – is a significant problem in the United Kingdom; indeed, it is estimated that approximately 2.6% of the population experience clinical depression and many more people experience ‘subthreshold’ depressive symptoms (Information Centre for Health & Social Care, 2009).
For the past four decades, the primary treatments for mild to moderate depression have been antidepressant medication and psychological therapies (British Psychological Society & Royal College of Psychiatrists, 2010). Indeed, medication and therapies are the basis of the UK’s current guidelines for the treatment and management of mild to moderate depression in adults (British Psychological Society & Royal College of Psychiatrists, 2010). However, as will be discussed in the following section, with the increasing prevalence of depression both globally and in the UK interest in ‘novel’ treatments for mild to moderate depression – including low impact physical exercise such as walking, physiotherapy and aerobics, etc.– is growing……………………………………………..