LAS VEGAS — The Celtics are making a deeper plunge into the sports science realm, parting ways with longtime trainer Ed Lacerte, while strength coach Bryan Doo has chosen to move on.

The work the latter began with rookies Jayson Tatum and Ante Zizic will continue to have an effect.

“The team was making some changes and looking at some new and different things, and I think it’s really good that they’re doing that,” Doo said. “But when I looked at what was going to be needed from me, I had to make some decisions. They gave me options, but when I looked at everything, I decided to make a clean break. I’ve got five little kids at home. I don’t want to miss them growing up, and I’ve already missed too many things. My wife’s been a single parent for a long time. And I don’t get to see my parents enough.

“I love the Celtics, and I can’t tell you how much of a dream job this has been. I am so grateful to the team and all the great people I’ve worked with and how they were willing to work with me on this, but then you start thinking about things. This seemed like the right decision.”

Doo also has a private company that he founded, Optimal Fitness, and he may be getting some additional clients. A number of former and current Celtics have already asked if they can still work with him.

According to Doo, the game plan for Tatum and Zizic this offseason has already been set.

“Jayson is special, and not just in the basketball sense,” he said. “And Ante is one of the hardest-working people I’ve met. He will do what it takes to get better.

“He’s a Perk-like hard worker,” he added, referencing Kendrick Perkins.

As what Tatum, the No. 3 overall draft pick, needs to work on, Doo said, “I think strength’s the most important thing for Jayson and just also understanding his body.”

The age-old question with hoop players and weight training is what it will do to their more delicate shooting skills. But Doo dismisses the issue.

“I think people who have touch, have touch,” he said. “It’s not like we’re putting body builder’s muscles on them. We’re just trying to make them stronger. But I think it’s a misnomer that getting stronger gets in the way of touch. People that know how to shoot can shoot whether they lift or not. Steph Curry lifts all the time, and that guy can shoot. No one’s worried about him.”

When it was pointed out that Michael Jordan followed his lifting schedule religiously, even hitting the weight room on game days in the playoffs, Doo nodded.

“So I’m not worried about that,” he said. “For us, it’s more body control and core strength. The nice thing about Jayson for me is that he’s very relaxed. I’m not worried about the basketball stuff. I leave that to the coaches. I just need to get him stronger and teach him how to be stronger in a defensive stance and also just how to move better. He moves well, but we have to teach him how to move better.”

Zizic is a different project, though strength training will also factor into his plan. The 7-footer from Croatia is a willing combatant, but he has to get ready for the speed of the NBA, as well as the much longer schedule.

“With Ante, I talked to one of our scouts and gone through all his programming and what he’s done the last two years,” Doo said. “I wanted to see where he needs to get his breaks and where he needs to go harder.

“It’s a faster game than in Europe. At practices, we’ve talked about the differences, and right now it may be a little overwhelming at times. But he’ll get there. He works extremely hard. He’s hard-nosed, and I think he’s got great work ethic, so he’ll have no problem getting better.”

Added Doo: “I really think the Celtics are in a great position. You’ve got so many guys on that team that are committed to working hard and getting better. Guys like Isaiah (Thomas) and Marcus (Smart) and Al (Horford) and so many others really put in the time in the offseason. I can’t wait to see how good all these guys are going to be this year.

“I’ve been so lucky to work for an organization like the Celtics. I can’t begin to tell you how great it’s been to be with these guys for the last 14 years.”