February 28 — 29, 2008 Advisory Committee Meeting
Subcommittee Report: Mental Health
Rod Dishman, Ph.D., led discussion on the subcommittee report on
mental health. The methodology the subcommittee utilized included meta-analytic
or otherwise systematic reviews of studies of mental health published since
1995. The questions researched included:
Does physical activity protect against the onset of disorders
Does physical activity reduce symptoms?
Do the effects of physical activity on symptoms differ
according to age, gender, race/ethnicity or medical condition?
Do the effects of physical activity vary according to features
of physical activity including type, intensity, or timing?
The topics the group reviewed included depression, anxiety,
distress/wellbeing, cognitive function and dementia, sleep, self-esteem, chronic
Overall the scientific evidence from prospective cohort studies
and randomized controlled trials supports the overall conclusion that regular
participation in moderate-to-vigorous physical activity is associated with fewer
symptoms and incident cases of major depression, fewer symptoms of anxiety and
distress, reduced onset of cognitive decline and onset of dementia and enhanced
feelings of well-being, cognitive function, sleep quality, feelings of energy
and self-esteem. The outcomes are generally positive for men and women of
differing ages, nationalities and health status; however, there are few direct
comparisons according to ethnic groups. The evidence from both observational and
randomized controlled studies suggests a dose-gradient for depression symptoms
that occurs within current public health recommendations for
moderate-to-vigorous physical activity. There is insufficient evidence to
determine whether an increase in fitness is necessary for mental health
benefits. Positive relations seen for depression and self-esteem may be a
surrogate index of intervention adherence.
Future research needs include more prospective cohort studies
and tightly controlled RCTs, especially for anxiety and sleep disorders. Also,
more studies that manipulate standardized features of physical activity and its
setting are needed. Accelerated synergy between human brain imaging studies and
neuroscience studies using animal models of human disease to elucidate
biological mechanism and more modeling of social-cognitive mediators of mental
health outcomes and studies of gene-environment interaction are needed.