General Benefits of Singing:
- improved mood.
- improved health.
- group singing creates a positive, supportive environment.
Physical Effects of Singing:
- releases endorphins, the brain's "feel good" chemicals.
- Singers show significantly decreased anxiety and depression rates.
- Proper use of breath reduces stress.
- singing for a crowd builds confidence.
- aerobic benefits (more oxygen in the blood for better circulation).
Psychological Effects of Singing:
- distraction from worries (creates a "stress-free zone").
- keeps the brain active (melody, harmony, tempo, dynamics, etc).
- positive social interaction.
- independence (solos, leadership roles, etc).
- teamwork.
- develop creativity through improvisation.
Note: all information found on this page was paraphrased from the following article on How Stuff Works?