"competitive activities" is correct and usable in written English.
It can be used when referring to activities that involve competing against each other. For example, "Many schools offer competitive activities such as sports and debate to help students stay engaged."
Very much interested in all competitive activities invented by Europeans.
It proposed setting up a subsidiary that would take over competitive activities such as corporate lending and investment banking.
The Korean Workers Party, the military and citizens all engaged in competitive activities to attract foreign cash, but in order to keep up with socialist appearances such enterprises were named "ABC Factory" or "123 Operation".
She is looking for winners, and winners of a certain sort: survivors in highly competitive activities in which a single physical, mental, or technical skill can be cultivated through relentless practice.
Orwell's rewrite: "Objective consideration of contemporary phenomena compels the conclusion that success or failure in competitive activities exhibits no tendency to be commensurate with innate capacity, but that a considerable element of the unpredictable must invariably be taken into account".
The complementarity of peace chiefs and war leaders and the occurrence of competitive activities between neighbouring groups including ball games, hunting contests, and trading expeditions imbued traditional social structures with a characteristic dualism.
They played at a club in Wimbledon, a spot more famous for a different competitive activity.
In the US, McDonald's blamed the sales decline in February on "ongoing aggressive competitive activity".
(Such competitive activity is an example of what has been called "peer-polity interaction").
Extreme sports seemed like child's play; sex became a competitive activity.
With the advent of ingenious microtechnology, Top Golf makes golf practice a competitive activity.
