BEAVERTON, Ore. -- A trimmed-down, high-energy LeBron James officially unveiled his new "LeBron 12" signature sneakers at Nike World Headquarters on Tuesday.

Following a video presentation detailing James' career and the technology behind the sneakers, James told a small group of reporters that a "very strict" offseason diet was responsible for his slimmer physique.

"I had no sugars, no dairy, I had no carbs," the four-time MVP explained. "All I ate was meat, fish, veggies and fruit. That's it. For 67 straight days."

Describing the diet as a "mental challenge," James said that the initial plan was to cut back for a month, but that he opted to keep going because his body felt so good. Although he refused to divulge exactly how many pounds he has dropped -- joking that it was just "a couple" -- his frame looked smaller than at any point since at least 2010.

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James plans to put some of the weight back on prior to the season for physical protection, but it sure looked like he is preparing his body to play at a faster tempo in 2014-15. After all, Miami played at the league's third-slowest pace last season, thanks to a roster that was loaded with aging veterans and the need to accommodate Dwyane Wade's knee injuries. Meanwhile, Cleveland's roster includes Kyrie Irving, one of the fastest end-to-end players in the league, and Kevin Love, arguably the best outlet passer in the game. And then there's James, who as a Nike/ESPN promotional video noted, can cover the length of the court in just nine strides (an average player requires 13) and he needs just 0.8 seconds to go from the three-point line to the basket.

Cleveland's philosophical approach and style will ultimately be decided by new coach David Blatt, but James made it clear that he wanted his latest sneaker to be able to keep up with him. The "LeBron 12" incorporates "Flywire" technology to maximize strength without adding weight, and the shoe's sole incorporates five multi-color hexagonal Zoom Air cushions that are located specifically on pressure points where the shoe takes impact during gameplay.

"[It was a priority] for me to be able to have a shoe that allows me to be fast, not weigh me down," James explained. "The new technology is lightweight. It allows me to explode. When I land, it allows me to absorb the landings. It's great."

Judging from the immediate responses on social media, the rainbow-colored cushioned soles are a bit polarizing. Of greater concern to James than those push-the-envelope aesthetics? Whether the shoes will stand up to his in-game needs. Last season, James drew some media attention for switching out of his "LeBron 11" signature sneakers during games. His frustrations with that shoe led Nike to begin the design and engineering process for the LeBron 12 earlier than usual, and James said he has been testing the latest iteration for roughly a month with no issues.

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"That's the great part about my partnership with Nike. ... [If something isn't right], we're going to continue to go back to the lab to figure it out," James said. "I was able to wear the shoe some games, some games I wore the 'Soldier' shoe. [The issues with the LeBron 11] hurt both of us. We loved the shoe so much, the 11, but it wasn't performing how we wanted, the way that Nike and myself are capable of performing. We started to get on this [12 model] right away. ... It's given me great responses."

The sneaker unveiling was a rare public appearance in what has been a mostly quiet summer for James since he announced he was returning to Cleveland in an essay with Sports Illustrated's Lee Jenkins. Don't mistake his low-profile summer for a lack of enthusiasm; James gushed about Irving's MVP performance for USA Basketball's gold medal-winning World Cup team. He even went a step further, suggesting that his two new All-Star teammates have the potential to be the best players in the league at their respective positions.

"I believe Kyrie can be the best point guard in the league very soon, and Kevin Love is already in the discussion as far as being the best power forward in the league," James said. "We have so many great [power forwards]: Tim Duncan, if he's playing center or power forward, Dirk Nowitzki, LaMarcus Aldridge, Chris Bosh, Pau Gasol is still very good. But that's my vision, to maximize [Love's] potential, and his potential to be the best at his position."

That sound you hear in the distance is the hype machine powering up. If what James predicts comes true -- that Irving develops into the league's best floor general and Love is soon regarded as the NBA's best four -- wouldn't that potentially give the Cavaliers' "Big Three" the edge over the Heat's "Big Three"?

"That comparison is going to be brought up because it's good conversation," James acknowledged, refusing to pick a side. "The Big Three discussion is this whole thing that goes on in our league. It's not new. The Big Three has been going on forever. You had Jerry West, Elgin Baylor and Wilt Chamberlain. You had [Larry] Bird, [Kevin] McHale and [Robert] Parish. You had Magic [Johnson], [James] Worthy, Kareem [Abdul-Jabbar]. [Michael] Jordan, [Scottie] Pippen, [Horace] Grant. Jordan, Pippen, [Dennis] Rodman. Jordan, Pippen, [Toni] Kukoc. This Big Three thing has been around forever, like dinosaurs. Going back all the way to [Bill] Russell, [John] Havlicek and Bob Cousy. It's not new, it's just more of a thing now."

James rattled off his many historical examples in a rapid-fire manner, and it was more than a little intriguing to hear him mention Jordan in three separate combinations. Was this a little between-the-lines evidence that James watched and learned from the reformulation of the Bulls' championship teams?

There was no need for guesswork when it came to gauging Jordan's shoe-pitching impact on James, who said that he hopes to one day have his "own standalone brand, where I can sign other athletes that fit my motto," a la Nike's popular Jordan Brand. But, first, he has more pressing business to take care of on the court.

"Winning is the most important, that's what I learned from Mike," James concluded. "Winning is the number one thing and everything else will take care of itself. I've had a few losses that I'm not too happy about, but I'll be alright."

The "LeBron 12" sneakers will be released in seven initial colorways. The first version -- dubbed the "NSRL," which is the acronym for Nike's Sport Research Lab -- will launch on Oct. 1 in China and Oct. 11 everywhere else. The shoes will retail for $200. Additional images of of the initial colorway, as well as a full release schedule, are below via Nike.com.

LEBRON 12 NSRL – James wasn’t made in a lab, but he is made better by Nike’s research, testing and analysis. The LEBRON 12 lead colorway reflects the process of turning data into design to create superior performance footwear. Launch: Oct. 1 in China; Oct. 11 globally.

LEBRON 12 Heart of a Lion – James has demonstrated the courageous heart of a lion while being tested both physically and mentally over his 11-year professional career. Launch: Oct. 30.

LEBRON 12 Dunk Force – Inspired by the power of James’s statement tomahawk dunk and equated to the speed and force of a helicopter rotor blade. Launch: Nov. 11.

LEBRON 12 Instinct – James’s keen 20/20 eyesight combined with his uncommon speed and agility translates to pinpoint, instinctual decisions, much like the way a hummingbird sees and navigates. Launch: Nov. 22.

LEBRON 12 Six Meridians – A key component of James’s training recovery and preparation is massage therapy. The ancient Chinese practice of reflexology releases energy to different points of the body, or meridians, when massaging pressure points in the feet and hands. Launch: Nov. 29.

LEBRON 12 Trillion Dollar Man – Are we looking at the athlete of the future today in LeBron James? Inspired by James’s legendary work ethic and physical gifts combined with Nike’s finest performance technology. Launch: Dec. 1.

LEBRON 12 Data – James is arguably the most dominant player in the game today, with the statistics to support that claim. Launch: Dec. 20.