Alternately you can just keep the names/numbers of all the people in your cycling group, in a text file separated by SEMICOLONS
Open the text file, copy the line, paste into the white box of an SMS, and press send

e.g. your line is:
John Smith;Ann Smith;Peter Thorn;Jack King

Paste and send. Phone will only ask for clarification if one person has multiple numbers, or two people have same name