"Horseback riders" refers to people who sit on top of horses and use them for transportation, leisure activities like riding for fun, or participate in sports like horse racing or rodeo events. Full definition
By the way, this series of exercises seems like it would be really good for horseback riders. (hab-it.com)
She became interested in animal care and Veterinary medicine in middle school when she was a competitive horseback rider. (apchospital.com)
This horseback riding is great for both experienced horseback riders as well as for those whose first time it is on a horseback. (bluesurfsanctuary.com)