​PHILADELPHIA — For many power hitters, aging often brings a decline in their swing.For Kyle Schwarber, it has brought the exact opposite: improvement.Since joining the Philadelphia Phillies in 2022 as a free agent, Schwarber has refined his swing and produced some of the best numbers of his career, cementing his place among baseball’s premier power threats.”I hope so,” Schwarber told USA TODAY Sports on Monday at Citizens Bank Park ahead of the MLB Home Run Derby when asked if he’s beating Father Time with his swing. So what’s been the key to success for Schwarber, who was non-tendered by the Chicago Cubs after the 2020 season before reviving his career with the Washington Nationals and Boston Red Sox, and ultimately finding sustained success in Philadelphia?He mentioned adapting his swing as baseball continues to adapt itself as a game, as well as trying to “stay the same guy every year” by sticking to his routines, which begins with hitting off the tee.”Being able to address different things and feeling that if you can look at your season from top to bottom at the end of the year and try to address things that you need to get better at and not just be okay with it,” Schwarber said. “… The game’s changed from 2015 when I first came in to where it’s at now.”Schwarber has hit 219 homers in five seasons with Philadelphia, second only to Aaron Judge’s 227 during that span. He sits 16 shy of Babe Ruth’s MLB record for most home runs in a player’s first five seasons with a team, with only Mark McGwire’s 220 with the St. Louis Cardinals in between Schwarber and Ruth. “You can go back 20 years, you can go back to Babe Ruth, what he is doing now is unbelievable,” former Phillies shortstop and manager Larry Bowa told USA TODAY Sports back in May.To further underscore Schwarber’s dominance with the Phillies, he hit just 153 homers across his first seven MLB seasons. He’s already launched 66 more in less time in Philadelphia, as he has reached at least 45 home runs in three of his four seasons.”Think it helps to take the glove away from him and all he has to do is carry his bat. We joke with him about that a lot,” Phillies first baseman Bryce Harper joked Monday about Schwarber’s transition from the team’s left fielder in 2022 to a full-time designated hitter in recent seasons.Phillies interim manager Don Mattingly didn’t necessarily agree with Harper’s assessment and the notion being an everyday DH has made hitting easier for him. “You still have to be able to hit,” Mattingly said on Monday. “DHs are better, it seems, when they get older because now they know they’re swinging, they know what they do, they know how to get ready.”Schwarber credits that success to working with Phillies hitting coach Kevin Long, who helped revitalize his career in Washington in 2021, and the assistant coaches he’s had at both stops. “They do such a great job of making sure that I just stay with what I need to do and keep me on track,” said Schwarber