LAS VEGAS -- Warriors big man Marreese Speights has spent the offseason running on a treadmill in which only the power generated by his footsteps will turn the belt.

Speights said Monday that his motivation for beginning his offseason conditioning program earlier was to come into training camp in better shape than he did last season after signing a three-year, $11 million contract.

"Because I feel like last year I started off bad," Speights said after meeting with new coach Steve Kerr and visiting the Warriors' summer league team. "I didn't like the taste in my mouth. I feel like I ended the season good, and I'm going to take the momentum to next season."

The 6-foot-10, 255-pound Speights averaged 6.4 points and 3.7 rebounds in 12.4 minutes per game last season, for a time falling out of coach Mark Jackson's rotation.

Kerr said Speights looked good and envisioned the 26-year-old as a reserve center who would back up Andrew Bogut and perhaps be used over Festus Ezeli against smaller teams without a dominant big man.

Speights after hoisting up a career-high 31 3-point attempts and making only eight (25.8 percent) said he could be both a stretch center and forward but was first focusing on getting into better shape.

"Last year, I really started (offseason conditioning) late," Speights said. "That was my fault, so I feel like this summer I just know every day I can do a little something to keep me in game shape. I feel pretty good, but I still can improve more.

"I ain't really worried about basketball-wise. I'm just worried about conditioning, for real."

Said Kerr: "We're going to need him to back up that center spot. So he'll be a factor for us, but he's got to come to camp in great shape."

  • Forward David Lee withdrew from the USA national team training camp roster that was announced Monday while recovering from "very minor" surgery a few weeks ago to address a core muscle injury, according to the Warriors.

    The Warriors expect Lee to be fully recovered in early August, but according to the team, he does not want to rush his return to the floor.

    "He's fine," Kerr said, adding that Lee had been working out.

    Lee, 31, underwent a surgery for the third consecutive offseason. He had procedures to repair a torn right hip flexor in 2013 and torn abdominal and abductor muscles in 2012.

    Lee, who averaged 18.2 points and 9.3 rebounds last season, joined teammate Andre Iguodala (knee tendinitis) in missing the USA Basketball training camp because of injury.

    The Warriors are the only team with more than one player on the national team roster participating in the July 28-Aug. 1 training camp at UNLV, with Stephen Curry and Klay Thompson among the 19 players expected to compete for spots on the Americans' FIBA World Cup team.

  • The Warriors currently can afford to sign free agents for minimum contracts because of salary cap constraints and are interested in bringing back Brandon Rush, who tore an ACL while with the team in 2012.

    Rush, who played in 38 games for Utah last season, is scheduled to work out for the Warriors and other teams interested in signing him.

    For more on the Warriors, see the Inside the Warriors blog at ibabuzz.com/warriors. Follow Diamond Leung on Twitter at twitter.com/diamond83.