A LITTLE BIT OF RESEARCH ON THE BENEFITS OF  GROUP SINGING

Belting Out Music Is Great for Your Health, And Here’s Why
Go ahead and sing it loud. https://www.goodhousekeeping.com/health/news/a47211/singing-health-benefits/

http://worldsingingday.org/research-on-group-singing/

http://www.howtosingsmarter.com/choir/

http://theconversation.com/choir-singing-improves-health-happiness-and-is-the-perfect-icebreaker-47619
http://singfit.com/clinical-research-on-the-benefits-of-singing/
https://heartresearch.org.uk/fundraising/singing-good-you
https://www.telegraph.co.uk/news/health/news/10496056/Choir-singing-boosts-your-mental-health.html
http://ideas.time.com/2013/08/16/singing-changes-your-brain/

NOTE: There is a lot more research and anecdotal evidence that shows singing is a good idea. I have experienced it in myself and have seen it in others. It’s not a strange concept.