Bartel flew to the USA the day after the Cats defeated Greater Western Sydney at Skoda Stadium in round 11.
He headed to the Texas city of San Antonio where he watched the Spurs play in the NBA finals.
The three-time premiership player returned to Australia last Friday and hit the training track with his teammates at Simonds Stadium on Wednesday morning.
"I've caught up with Jimmy and he had a great time," Geelong coach Chris Scott before the training session. "He's come back ready to go.
"His program over the break was well planned and we spent quite a bit of time on it, and we're really comfortable with the outcome.
"To be honest, the proof will be in the pudding, but I'd be very surprised if Jimmy Bartel doesn't play great footy in the last half of the season.
"We understand that people out there in the football world will have differing views (about Bartel being allowed to go to the United States).
"To be honest, there are differing views within our football club as well. But it was a well considered decision and one that we're very, very comfortable with."
Although Bartel training strongly on Wednesday, Scott says he is only "50-50" to play against the Lions.
"He's come back in pretty good shape and he's feeling pretty good," Scott explained.
"He certainly would be available to play if we really needed him to for this week.
"But we consider more than this week when we manage our players, so if it's going to be better for him later in the season not to play (against the Lions), then we'll probably do that."
"He has had some issues that we've had to manage over the last 18 months."
Defender Harry Taylor, ruckman Mark Blicavs and half-forward Steven Motlop, who all missed Geelong's last game against the Giants, will return to face the Lions.
Taylor Hunt, who has recovered from the broken collarbone he suffered against Essendon in round seven, will also make his competitive return this weekend.
"He's certainly play," Scott said. "Whether he plays AFL footy or not is something we've got to decide.
"He's trained really well in our match simulation and we don't think his footy touch is going to be too much of an issue.
"To be brutally honest with you, we're probably leaning towards playing him at AFL level."
Adam McNicol covers Geelong news for AFL.com.au. Follow him on Twitter at @AFL_AdamMcNicol