Yes, many cyclists use whey protein. Whey protein is a byproduct of milk and the main component in many protein powders.
Many athletes supplement their diets with whey protein after a ride to help with muscle recovery and repair. Whey protein is rich in leucine, an amino acid shown to stimulate muscle protein synthesis . (You can read more about leucine here.).
 Kerksick, C.M., Wilborn, C.D., Roberts, M.D. et al. ISSN exercise & sports nutrition review update: research & recommendations. J Int Soc Sports Nutr 15, 38 (2018). https://doi.org/10.1186/s12970-018-0242-y