With training camp underway, we are less than a month away from the start of the 2013-14 NBA season. For the eventual champions, this week is the beginning of a brutal nine-month grind that will feature over 100 pre-season, regular season and postseason games in 29 different cities spread out across the North American continent. To figure out which team it will be, one question stands out above all the rest: who will keep their stars healthy?

Three years after “The Decision”, the Miami Heat being two-time defending champions seems almost inevitable. Of course, when it comes to sports, nothing is inevitable until it already happens. In 2012, Chris Bosh’s abdominal injury left the Heat on the brink of elimination twice. Dwyane Wade’s struggles with his knees have become an annual occurrence; in the 2013 NBA Finals, Miami had a net rating of -54 when their second best player was on the floor.

If the Heat can make it back in 2014, they will be the first team since Larry Bird’s Boston Celtics to go to four consecutive NBA Finals. Playing that deep into June takes a tremendous toll on players, both physically and mentally. For three years running, Miami has had the shortest off-season in the league. This season, keeping everyone healthy and avoiding fatigue will be as big a concern for Erik Spoelstra as anything that happens on the court.

Despite the health issues of two of their Big Three, the Heat have to count themselves as lucky for dodging the biggest injury-related bullet of them all. LeBron James, whose won four of the last MVP awards, has been indestructible since he entered the league. Not counting the lockout, he’s never played fewer than 74 games in a season. However, all it takes is one awkward landing or someone rolling up on the back side of his leg to change everything.

Before his run-in with Patrick Beverley, Russell Westbrook had been just as unbreakable. In five seasons in the NBA, in spite of his high-flying and sometimes reckless style of play, Westbrook was 394-394 in terms of games played. And while his injury exposed some long-standing issues in Oklahoma City, it’s important to keep their second-round loss to the Memphis Grizzlies in perspective. A healthy Westbrook and Kevin Durant cover up a lot of holes.

Westbrook’s injury opened up the bracket for the San Antonio Spurs, who swept the Grizzlies in the Western Conference Finals. If Tony Parker had been the star point guard knocked out of last year’s playoffs, the narrative around both teams would be radically different. Instead of being the preseason favorite, everyone would be talking about how the Spurs are too old to contend. That’s why Game 6 hurt so bad for San Antonio: so much had to go right just to reach that point.

In the NBA, a title window is only as open as the health of your stars. That’s the biggest reason for optimism in Oklahoma City: Durant, Westbrook and Serge Ibaka are all under 26. In contrast, Parker is 31, Manu Ginobili is 36 and Tim Duncan is 37. Even if Westbrook isn’t ready for the start of the season, there’s little question which Big Three is more likely to be healthy next June. There’s an element of luck in any title run, especially for an older team.

Maybe the most telling statistic for the Los Angeles Lakers last season was 258, the number of minutes that Kobe Bryant, Steve Nash, Pau Gasol and Dwight Howard played together. Howard, the youngest of the four, was a shadow of himself as he recovered from back surgery. Before that, he had been the NBA’s Ironman in the middle, earning the title of best center in the game almost by default, after Yao Ming, Andrew Bogut, Greg Oden and Andrew Bynum were sidelined.

In hindsight, it seems obvious that an older team like the Lakers would implode. However, just two years before, the Dallas Mavericks won a championship with Dirk Nowitzki (32), Jason Terry (33), Shawn Marion (32) and Jason Kidd (37) playing major roles. Tyson Chandler, the defensive-minded center who pushed the Mavericks over the top, had been in and out of the lineup for most of 2009 and 2010. In 2011, he played in 95 regular season and postseason games.

This year, the Brooklyn Nets are the ones rolling the dice. If they can keep everyone healthy, they have as much talent as anyone in the NBA. However, to knock off Miami, they will need Kevin Garnett, Paul Pierce, Brook Lopez, Joe Johnson and Deron Williams at 100%. That’s going to be no easy task, even without counting the number of miles KG and Pierce have put on their body. The season hasn’t started and Williams is already dealing with an ankle injury.

Over the last two years, the NBA has been hit by a rash of high-profile injuries. Westbrook, Kobe, Dirk, Derrick Rose, Kevin Love and Rajon Rondo were all conspicuous in their absence in last year’s playoffs. Dirk and Love’s teams didn’t even make the postseason, primarily because they were missing their star PF for a good portion of the year. The Lakers and the Celtics, only a few years removed from the 2010 NBA Finals, were dead men walking by May.

The last two years have been one of the darker timelines for the Chicago Bulls, who have essentially been spinning their wheels since Rose’s ACL injury in the first game of the 2012 playoffs. In 2011, the year Rose won his MVP award, the Bulls were stopped by the Heat in the Eastern Conference Finals; who is to say how things would have gone if Rose and LeBron had switched places in May 2012. Health is why every deep playoff run is precious; it can be taken away at any time.

In a sport where championships determine legacies, it’s hard to accept that some things are beyond anyone’s control. The reality is that if we knew which stars would and would not be healthy, making preseason predictions would be easy. So as we begin a new NBA season, the only thing left for fans of all 30 teams is prayer. Grant us the serenity to accept the things we cannot change, the courage to change the things we can and the wisdom to know the difference.