The offseason directive has already been issued, and it’s a simple one: Show up for preseason camp in shape.

Heat president Pat Riley met with reporters Wednesday and laid out the Heat’s offseason plan. It involves keeping the large majority of the team together and “improving from within” to better prepare itself for what will be a run at history — three consecutive championships. There have been only five instances in NBA history of teams winning at least three consecutive titles: Minneapolis Lakers (1951-54), Los Angeles Lakers (1999-2002), Bulls (1990-93, 1995-98), and the Celtics, who won eight in a row (1958-66).

“We need to improve,” Riley said. “Erik [Spoelstra] and I have already had two conversations about … because we’re a little older, they have to come back leaner, lighter, stronger, quicker and faster, so when you get a little bit older, you’ve got to dedicate yourself to diet and conditioning and training and becoming a better player skill-wise.”

For LeBron James, that means an offseason dedicated to the one aspect of his game that could use significant improvement, his free-throw shooting. James shot 75.3 percent from the foul line last season, which was his lowest percentage in five years.

“Our goal now is to get him up over 90 percent from the free-throw line — or he will take that on as a goal — and then Erik’s goal is to get him back to attempting 12 free throws a game,” Riley said, “if the league will ever stop allowing players to tackle him at half court.”

For other players, returning healthy and lean is the goal. Not that anyone needed reminding, but Riley pointed out how the Heat’s 2006 championship team didn’t seem to take repeating very seriously. In particular, Shaquille O’Neal was overweight, although Riley didn’t name O’Neal specifically.

“I’ll let you figure it out,” Riley said.

As for changes in the Heat’s 2013 championship roster, Riley doesn’t expect much, despite rampant speculation from national-media outlets that the Heat would consider trading Chris Bosh.

“I don’t like to change that much, not when you’re winning,” said Riley, who pointed out that Bosh made five plays in the span of 20 to 30 seconds at the end Game 6 to keep the Heat alive in the NBA Finals.

When the team reconvenes in late September, Riley said he hopes 14 of the roster spots to be filled by players who were under contract in the 2013-14 season — the one exception being Juwan Howard, who likely will be replaced by a free agent.

“We’re going to cannibalize the market in August and September if we can, and hope that we can bring everybody back,” Riley said. “It’s a great team.”

The NBA Draft is Thursday night, but without a pick in the draft, the Heat isn’t expected to partake. Riley didn’t completely rule out dealing itself in for a second-round pick, but noted that “after the first 10 or 12 picks, I’m not so sure that player is out there.”

“We’ll have our top 60 players rated,” Riley said. “They will star certain players that maybe we like more than others in case we truly want to find a way to get into the draft. There are a number of situations when it comes to drafting a player and putting him in Europe possibly for the future.