"I play at midnight," he tells Ellen DeGeneres on her talk show Wednesday. "Kind of vampire style."
Thankfully, the star, 55, can actually find people to play with him then – his household staff.
"The house manager and the house maintenance person, they both live my hours, so ... at midnight we go to the local tennis court," he says.
Also piping in on the show was Travolta's daughter, Ella Bleu, 9. She's making her big-screen debut opposite dad and mom Kelly Preston in the upcoming movie Old Dogs.
"It was really fun to see me," she says. "I was like 'Yes! Not only just my parents, but it's me up there too.' "
The interview keeps it mostly lighthearted, but Travolta does touch on the recent tragedies of son Jett's death, and the subsequent mistral for two Bahamians who allegedly tried to blackmail the star.
"I just want to take one moment to thank each and every one of you throughout this country, throughout the world for all your support and all your love for our family," Travolta says. "Thank you very much."