Refers to a male with unfulfilled dreams of sports stardom who then pressures his children into playing sports in the hope they achieve the stardom he failed to achieve.
The sports jockey is the male equivalent of the stage mom
Wife 1: (Sighing) My husband enrolled (insert child's name here) in softball, gymnastics, tennis, and track this year at school.
Wife 2: You poor thing. You married a sports jockey too?