Sportive is a good adjective to describe fun-loving people who are playful and lively, like your sportive friends who run straight to the water or hit the volleyball court when they get to the beach.
Sportive describes people whose idea of fun is being in motion. They run around, hike, bike, play sports — anything but sit still. There is another meaning of sportive that doesn't require so much action. Those sportive types are sports fans, who may be athletes themselves, or just big fans of a team or a sport.