• 15 million Americans suffer from depression.
• 10 -12 million Americans suffer from anxiety or stress reactions.
• The hectic pace of the Westernized, technological society.

Distraction Hypothesis:
This hypothesis maintains that exercise acts as a "time-out" from stressful life events. Exercise does not produce greater reductions in anxiety than control conditions, but the anxiety-reducing effects last longer.

Endorphin Hypothesis:
This hypothesis states that exercise releases endorphins that can give the exerciser a "natural high."

Exercise & Depression:
Exercise appears most helpful in relieving depression for subjects who are clinically depressed, as opposed to normal.

• Regular exercise has been shown to be related to long-term decreases in depression.
• The greater the total number of exercise sessions, the greater the decrease in depression.
• Exercise intensity is not related to changes in depression.
• The longer the exercise program, the greater the reduction in depression.
• The total exercise time per week is not related to changes in depression. 

Exercise & Anxiety:
Exercise is associated with, but does not cause changes in emotional states like anxiety.

"The Runner's High":

• The Runner's High is a "euphoric" sensation, usually unexpected, of heightened well-being, enhanced appreciation of nature and transcendence of time and space.
• Conditions facilitative of The Runner's High:
• Few distractions
• Cool, calm weather and low humidity
• Longer distances - at least 30 minutes of running
• Runners differ regarding how often they experience The Runner's High, and may require slightly different sets of conditions to get into it.

Research Findings:

• Aerobic activities such as running, swimming, and aerobic dance are associated with more positive changes in mood than are aerobic activities.
• Low-intensity exercise activities (e.g., walking) are associated with more positive changes in mood than are high-intensity activities.
• Exercisers demonstrate more positive mood states than do nonexercisers.
• Massage also is related to increases in positive mood states.

Personality:

• Regular exercise has been shown to be related to increased self-esteem.
• Exercise can help protect against stress-related illness, especially for hardy people.

Cognitive Functioning:

• Short duration, high intensity exercise enhances mental funtioning, whereas strenuous exercise for long-durations can inhibit performance unless the person is extremely fit.

What is Exercise Addiction?
Psychological and/or physical dependence on a regular regime of exercise characterized by withdrawal symptoms after 24 to 36 hours.

Withdrawal Symptoms:

• Anxiety
• Irritability
• Guilt
• Muscle twitching

Types of Exercise Addiction:

• Positive Addiction: (healthy habit)
• Negative Addiction: (exercise controls one's life)
• Only a small percentage of people have a negative addiction.

Results of Negative Addiction When One Cannot Exercise:
Not being able to exercise causes severe depression. Problems at home, work, and with relationships occur.

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