Manager Joe Maddon grinned when the question was asked.

The Cubs look like a different team since the All-Star break. They wrapped up a three-game sweep of the Pirates with an 8-3 victory Sunday. It completed a dominant series in which they outscored Pittsburgh 22-10.

What was the secret?

“It’s rest,” Maddon said with a shrug. “I mean, people don’t want to listen to that because it’s way too simple. It’s a simple concept. If you’re more rested, you tend to do what you do better. If you’re not, you tend to do it not as good.

“They don’t let pilots fly too long. They don’t let bus drivers drive too long. I don’t like to drive my RV more than six or seven hours. You lose something. We all do.”

The next challenge for Maddon will be to keep his players feeling fresh as the second-half grind awaits.

Everything clicked for the Cubs on a sunny afternoon. After falling behind 3-1 in the third inning, they closed the game with seven unanswered runs.

Jason Heyward, Albert Almora and Kyle Schwarber homered as part of a 13-hit effort. Kris Bryant, Anthony Rizzo, Victor Caratini and Robel Garcia had two hits apiece.

Oh, and Jose Quintana (7-7) notched his third consecutive quality start by limiting the Pirates to three runs in six innings.

“It’s a really good feeling, the sweep and to start the second half like this,” Quintana said.

Heyward provided the turning point with a go-ahead, two-run blast in the fifth.

It was his 15th homer, which is the most he has hit since 2012, and one of his most impressive of the year as the ball traveled 410 feet into the wind.

“I hit it great, and I wasn’t thinking about the wind, honestly,” Heyward said. “It did get out. But then [Schwarber] right after that showed me what it was like to cut the wind. That was funny for me.”

Schwarber’s 437-foot blast came one pitch after Almora hit his first career pinch-hit home run in the sixth. It was the seventh time this season the Cubs have hit back-to-back homers.

The Cubs also became the third National League team to reach 50 wins, joining the Dodgers and Braves.

Could a four-day break really explain this weekend’s success at Wrigley? Weren’t the Pirates rested, too?

“It’s more mental,” Bryant said. “You can play through the physical tiredness, but when you’re going at it every day and getting beat up like we were before the All-Star break, it’s more of a mental grind. I think we’re mentally rested, and that’s a good thing.”

The Cubs now stay home, where they are 32-16, to welcome the Reds for a three-game series.

Then comes another day off — and more precious rest.

Bryant and his teammates say they’re ready to make a second-half run. They fully expect that bumps and bruises will return, particularly with the team scheduled to end the season with 24 games in 25 days.

“We know we’re going to hit rough patches again this year,” Bryant said. “It’s just part of the game. But if we can find a way to minimize that and find a way to win three games in a row, win four games in a row, rather than win one, lose one, back and forth, that kind of just gets to you.

“If we’re able to come together as a team and pull together some wins where we shouldn’t win and win the ones that we’re supposed to win, I think we’re going to be great.”