Physical Activity & Mood November 21, 2002

Physical Activity and Depression Non-clinical depression Clinical depression (DSM) –loss of interest, lowered mood, at least 2 weeks –at least 5 of the following loss of appetite, weight gain or loss, sleep disturbance, decreased energy, psychomotor slowing, sense of worthlessness, guilt

Physical Activity & Non-clinical Depression Depression is reduced with physical activity Effect of exercise varies from small to medium

PA and Clinical Depression Depression is reduced with PA Effect of exercise varies from medium to large

Depression & PA: Moderators Task type Duration Combination of PA and psychotherapy provides best reduction

Why Does PA Benefit Mood? Cognitive explanations Physiological explanations

Cognitive Explanations Expectancy hypothesis

Cognitive Explanations Cognitive Behavioral hypothesis

Cognitive Explanations Social Interaction hypothesis

Cognitive Explanations Distraction hypothesis

Physiological Explanations Thermagenic hypothesis

Physiological Explanations Monoamine hypothesis

Physiological Explanations Opponent process hypothesis

Physiological Explanations Cerebral changes hypothesis (Cog. Func.)

Conclusion “If exercise could be packed into a pill, it would be the single most widely prescribed and beneficial medicine in the nation” (Presidents Council on Physical Fitness, 1997)

Exercise Addiction: How much of a good thing? Can an activity associated with SO many benefits have the potential to be harmful? –Exercise dependence –Physical activity and eating disorders –Physical activity and steroid use

Exercise Dependence Number of definitions have been provided for exercise dependence that include: –Behavioral correlates that might reflect dependence including PA duration, intensity & frequency –Psychological correlates including a pathological commitment to PA –combination of both of these People can be physically active 5, 6, or even 7 days a week who are NOT dependent

Exercise Dependence Not only indicated by behavior but also by psychological reasons underlying that behavior Diagnosed using DSM standards for substance dependence? Can be defined as a multidimensional maladaptive pattern of PA, leading to significant impairment or distress, as manifested by three or more criteria from a possible list of seven

Exercise Dependence Tolerance effects - increased amounts of PA are necessary to achieve desired effect OR individual has markedly lower effects from same amt. of PA Withdrawal effects - anxiety or fatigue are seen with cessation of PA, or PA is used to relieve or forestall onset of symptoms Intention effects - PA is undertaken with greater intensity, frequency, or duration than was intended

Exercise Dependence Lack of control - PA is maintained despite a persistent desire to cut down or control it Time - considerable time is spent in activities essential to PA maintenance Reduction in other activities - other social, work, or recreational pursuits are reduced or dropped because of PA Continuance - despite awareness of a persistent psychological physical or psychological problem, PA is maintained

Historical Contributions Frederick Baekeland

Exercise Dependence Research Hausenblas & Symons (2002) examined exercise dependence in over 2,300 exercisers who varied in their involvement Represents effects during periods of no physical activity Symptoms: Affective, Cognitive, Physiological, Social

Treatments of Exercise Dependence Adams & Kirkby (1997) interviewed 24 physiotherapists w/ED clients Treatments 71% experienced problems communicating--injured runners refused to stop exercising