The volunteers did yeoman's service cleaning up the park today.
yeoman's service
idiomArduous work, performed in a vigorous, committed manner.
Origin
disputed originAn allusion to stouthearted, dutiful labor performed by a yeoman.
Our assistant did yeoman's service during the busy season, working late every night to ensure we finished the project on time.
Throughout the long and difficult campaign, the dedicated staff performed yeoman's service, tirelessly managing every detail to secure the final victory.