"He's in the best shape of his life," receiver Kendrick Bourne said Monday. "He looks really good. His stomach is gone.
"When you're a rookie, you just don't know it until you go through it for a year. So he's definitely a lot more in shape than he ever was, just dominating in conditioning. It's dope to see."
Jones, the 2021 first-round draft pick from Alabama who started every game in his rookie NFL season, told reporters that has been a big part of his offseason plan.
"I just cleaned up my diet," the 6-foot-3, 214-pound Jones said after Monday's practice. "I've learned more this offseason than I probably ever have about nutrition, sleep, wellness, all that stuff.
"At the same time, I need to be able to maintain my weight and be able to take hits. There's a fine balance for every player. I've definitely trimmed down on the body fat, and I'll get a chance to bulk up before the season starts and be able to absorb hits."
Jones' improved physical makeup isn't the only notable change with the Patriots' offense, as longtime coordinator Josh McDaniels has departed to become head coach of the Las Vegas Raiders.
Monday marked the first time reporters were granted access to watch the Patriots practice this offseason, and head coach Bill Belichick's involvement with the offense was notable. In the final 11-on-11 drill, Belichick was reading off a card to Jones, who then relayed information to his teammates.
Former New York Giants head coach Joe Judge is working with the quarterbacks, while former Detroit Lions head coach Matt Patricia is with the offensive line. Both coaches also took leadership roles with the offense at times Monday.
Belichick hasn't named a coordinator or playcaller at this point.
"It's not my decision to make and we have plenty of time for all that. So right now, it's about the guys and I getting on the same page," Jones said. "It always goes back to the players, and we're excited to grow together and learn from whoever is coaching us."
Of Belichick spending more time with the offense Monday, Jones said: "Obviously he's a great defensive mind, but he also has great offensive knowledge."
Belichick's presence with the offense was also noted by Bourne, the six-year NFL veteran in his second season with the Patriots.
"He's been more present, helping us out," he said. "It's new, so he wants it to go a certain way. He's a defensive guy, so it's almost just embracing and taking advantage of the time we're going to get with him."
Last season, when Jones finished 352-of-521 for 3,801 yards, with 22 touchdowns and 13 interceptions, he was often seen on the sideline with McDaniels, who was also the team's quarterbacks coach. The two formed an instant connection.
Jones said he's happy for McDaniels to land a head-coaching job and also "excited to open up the next chapter" with Judge.
"He's done a great job coaching us," he said. "He's seen a lot of football, been around football for a long time, whether that be as a head coach, special teams, playing the position himself [in college].
"So he has knowledge that is very beneficial to me as a quarterback, and obviously, I'm going to learn with him. That's the goal, to kind of teach each other, and take what he knows, and then take the experiences that I have, and combine them and work together as a great team."
Meanwhile, Jones is excited about the Patriots' receivers, with trade acquisition DeVante Parker joining last year's core that includes Bourne, Jakobi Meyers, Nelson Agholor and tight ends Hunter Henry and Jonnu Smith.
"I'm really happy with the group we have," Jones said. "DeVante's done a great job coming in, working in a new system. It's a good group and we just have to keep elevating each other and push each other and compete."