This is multi-center, psycho-education randomized controlled trial, consisting of two periods with each of 6 months (i.e supervised and maintenance period). In the exercise intervention arm, during the first 6 months, participants will be asked to do moderate-intensity aerobic exercise 3-4 times a week, which will be supervised in person by physical educators/professionals. In the next 6-month maintenance period, participants will be asked to continue doing aerobic exercise at the same intensity and frequency, which will not be supervised in person by educators/professionals, but they will be sent reminders and report adherence weekly. All of the physical activity will be recorded by accelerometer at scheduled time points (e.g. the first week, 6 week, 3 month, 6 month, 9 month, 12 month). Psycho-education group will be given 6 sections of general psycho-education onsite and/or virtually dependent on the surroundings with regards to the impact of the COVID-19 pandemic. The main aim of this trial is to investigate the effect of long-term aerobic exercise on prevention depression in young people with subthreshold depression.
It is estimated that approximately 30% of child and adolescents manifest subthreshold depression, which can further develop into major depression with as high as 25%-50% within one year. The main aim of this trial is to investigate the effect of long-term exercise on preventing major depression and depressive symptoms in young people (aged 10-17 years old). Other aims include the underlying mechanisms of how aerobic exercise works and predictors for treatment response.