**3. Conclusion: implications of using exercise to impact anxiety, depression and PTSD**

There is abundant and ever increasing evidence that exercise can be of significant benefit in reducing adult affective disorders including PTSD. There are literally hundreds of empirical studies demonstrating the beneficial effects of exercise on adult anxiety and depression and these are major components of PTSD. There are also a growing number of studies showing that exercise can beneficially impact adult PTSD directly. The emerging research shows that it can be of value for adolescents and children. The benefit of physical exercise in reducing negative affect is that exercise fits within the natural ecology if childhood and adolescent activity. In contrast psychotherapy and psychotropic medication are alien to youngsters. Physical education classes often exist within their schools so exercise is seen as an integral part of the educational process and part of what it means to be student within the school system.

Further work is needed to develop empirically sound methodologies for investigating the role of exercise in dealing with PTSD and other affective disorders. Exercise has long been seen as being of value for the physical wellbeing of children, adolescents, adults, and seniors. Empirical findings indicate that exercise has beneficial effects on psychological functioning as well. Further research should examine its benefits as a method of prevention for children and adolescents at risk for internalizing disorders, i.e., troubling emotional states that do not find outward expression.
