Approach Examples of study types and characteristics Epidemiological Cross-section analyses; prospective analyses. Population-level intervention Green-space modification; personal computer-based interventions; cross-governmental approaches; work place based interventions; Setting: Whole population or sub-population. Clinical trial Randomized; placebo-controlled; blinded; pilot. Psychological and sociological study Qualitative and psychosocial analyses. Clinical neuroscience Methodology: Neuroimaging (e.g. structural and functional magnetic resonance imaging, positron emission tomography); serum and cerebral spinal fluid analyses. System: Neuroimmunology; neuroplasticity; oxidative stress; neurotransmission; hypothalamopituitaryadrenal axis physiology; mitochondrial physiology. Basic neuroscience Methodology: cell culture; rodent studies; neuroimaging. System: Neuroimmunology; neuroplasticity; oxidative stress; neurotransmission; hypothalamopituitaryadrenal axis physiology; mitochondrial physiology.

Table 2: Approaches to examining the role of physical activity in the treatmentand prevention of depression.