Are the Heat more vulnerable than ever?

MIAMI -- LeBron James has little interest in knowing the official human odometer reading.

But the physical and psychological wear and tear accumulated from his championship journeys with the Miami Heat certainly have added up over the years. Considering three straight runs to the NBA Finals through June, which produced consecutive titles the past two seasons, James and the Heat essentially have played the equivalent of four basketball seasons in the span of three years.

James has the championship hardware to prove it.

The scars, too.

“Obviously, I’m not 26 going into the playoffs like I was three years ago,” James said. “So as far as miles, we’ve got a lot more miles on our bodies because of how much basketball we’ve played. But I don’t feel more weight going into these playoffs than I felt last year or the year before, or the year before that.”

The Heat open their first-round playoff series against the Charlotte Bobcats in Miami on Sunday. But James and his teammates have already advanced deep into their toughest battle of the postseason.

As James suggested, the Heat are fighting off any notion they are weighed down by the task of trying to become the first team in nearly 30 years to reach the Finals four straight seasons and only the fourth franchise to win three consecutive championships.

Having finished 54-28, the Heat endured their lowest winning percentage of any season since James, Dwyane Wade and Chris Bosh came together in 2010. They’ve survived a seven-month grind during which nagging injuries forced Wade out of the lineup for 28 games and coach Erik Spoelstra to sort through 21 different starting lineups to fill the voids.

Now, the two-time defending champions enter the playoffs older -- six of their top nine players are in their 30s -- and arguably more vulnerable than they’ve been at any point. In addition to those factors, Miami limped into the postseason having lost 14 of their final 25 regular-season games and failed to secure home-court advantage throughout the playoffs, which proved to be essential last season.

Yet as defiant as they’ve ever been, the Heat insist none of those potential warning signs matter.

“On the outside, there’s more doubt,” said forward Udonis Haslem, who along with Wade are the lone players who have been with the Heat since their first championship season in 2006. “Within here, we're still confident in one another. We still know what we can do. We still understand what needs to be done and we know how to get it done. From the outside looking in, people might have a different opinion.”

Those opinions range from former Chicago Bulls guard Steve Kerr suggesting earlier in the season the mental and physical fatigue from the past three years would be too much for the Heat to overcome this season to win a third straight title the way his Bulls did twice in the 1990s with Michael Jordan.

Houston Rockets coach Kevin McHale, who starred on the last team that reached the Finals four straight years in Boston, said last month that the Heat have the perfect combination of talent and postseason experience to fight through all of the issues they’ll face along the way to their ultimate goal.

Standing between those two vantage points is a Heat team trying to maintain perspective.

Following a regular season where every decision was focused on the bigger picture, they now reach the postseason in which the collective mindset is all about taking care of the small details along the way.

“The regular season, the last part, was pretty rough on us with injuries, different lineups and just playing every other day for two months,” said Bosh, amid his least productive month of the season in April. “It was turning into a real difficult grind. But this is what you play 82 games for, and we have another opportunity to defend our title. There will be a lot more urgency. We're out of time. We can't really make many excuses or mistakes anymore. It’s easier to hold each other accountable in the playoffs.”

Having watched his team sputter down the stretch, Spoelstra was asked Saturday if he felt his team was capable of shaking off the recent struggles and reaching a consistently dominant level of play.

“There better be another level for us,” Spoelstra said. “I don’t talk about a [flipping a] switch or anything. We're grinding through the last six weeks, we were trying to figure it out and we couldn't get over that hump. But we have a clean slate right now. Our guys have a good perspective about it. They love this time of year. And that’s what I hope. I hope the competition will bring out another level in us.”

Wade subscribes to the switch-flipping theory, but only in the sense that each player should raise his individual levels of intensity and sacrifice to address the team’s larger priorities.

“It is a switch, but it ain't the switch everyone thinks it is and … flip the switch to be champions in the first game of the first round,” Wade said. “That’s impossible. Obviously, the bigger picture, we understand what we're playing for. But we have to play for today. And we have to focus on Game 1 versus the Bobcats. It’s the first team to 16 wins, and that’s a long, long way away.”

Both Wade and Bosh said there’s no reason the team should be focused on trying to “three-peat” right now, because it won't happen in the first game or series of the playoffs. But as the Heat get closer to their goal, they only expect the challenges to get tougher and the adversity to grow.

But that’s when players say they'll rely on the perseverance shown in previous tough spots in the playoffs. Since losing to Dallas in the 2011 Finals, the Heat have fought back from the brink of elimination to win titles in each of the last two postseasons. That resume includes winning Game 6 of the 2012 conference finals in Boston after trailing 3-2. Last summer, Miami won Games 6 and 7 at home after falling behind 3-2 to San Antonio in the Finals.

“The NBA is getting tougher, but I think every year, this team has, as well,” Wade said. “For what we've been able to overcome as a group, we've gotten mentally tough. We've built that. We've built those habits. And they will be there. We've got to pull from them at times, but hopefully not too many times.”

James has drawn a bit of additional inspiration entering the postseason from watching an ESPN documentary on the Detroit Pistons’ "Bad Boys" teams that won back-to-back titles in 1989 and 1990. As James watched how the Pistons went to the Finals three straight seasons but struggled to get there a fourth time, he turned to his wife, Savannah, and nodded toward the television.

“Who does that sound like?” James asked. “Sounds just like us. I know exactly what they're going through. We've been through so many battles, and every year is different.”

Meanwhile, Wade spent that same recent night watching the season finale of "Scandal," a hit TV series predicated on thriving through extreme measures of crisis management.

Sounds a bit like the Heat, too.