The Incredible Shrinking Leading Man?

The upcoming weekend will host a battle of the sexes at the box office, but will simultaneously also see a minor showdown between the old-school action hero and the new. In one corner, we have "The Expendables," which collects many of the great action-hero actors of the 80s and 90s together for another romp, punctuated with heavy artillery fire, fistfights, and a few explosions. Directed by and starring Sylvester Stallone, the nostalgia factor will be high. He'll be joined by Dolph Lundgren, Mickey Rourke, "Stone Cold" Steve Austin, and relative young 'uns Jet Li and Jason Statham. And in one scene, Bruce Willis and Arnold Schwarzenegger will be making cameos alongside Stallone, the first time the three greatest headliners of the 80s action genre will share the screen together.

Now in the other corner we have "Scott Pilgrim vs. the World," Edgar Wright's new video-game-flavored fable about a gawky twenty-something forced to do battle for love, against his new girlfriend's seven evil exes. The hero is played by Michael Cera, who can still pass for a teenager and a scrawny one at that. The contrast to the stars of "The Expendables" couldn't be starker. "Scott Pilgrim" will make up for the deficiency of muscles with loads of CGI special effects stylized to simulate comic book graphics, complete with the occasional "Batman"-esque onomatopoeia. Cera isn't alone this year among the slighter breed of action movie heroes. "Predators" swapped out Schwarzenegger for Adrien Brody, "Sorecerer's Apprentice" featured Jay Baruchel and Nicolas Cage, and the most memorable action scene of the year so far has been Joseph Gordon-Levitt's rotating hallway beatdown in "Inception."

Of course there are still plenty of more physically substantial actors around too. Jake Gyllenhaal bulked up for "Prince of Persia," Russell Crowe gave us our most solidly built "Robin Hood," and the most successful action star of the last few years has been Sam Worthington, the lead of "Avatar" and "Clash of the Titans." But these days you're as likely to find Michael Cera or one of his contemporaries getting in on the action. Jesse Eisenberg in "Zombieland." Shia LaBeouf in the last two "Transformers" movies with a third on the way. There's been some understandable grumbling from those who prefer their heroes literally larger than life, and all sorts of speculation as to why we're seeing so much downsizing of our leading men. Stallone recently told the Los Angeles Times that the downfall of the muscle men came with the rise of the superheroes, when it became possible to "Velcro your muscles on."

Superheroes are probably a symptom of a larger trend: special effects becoming more important to an action movie than the wattage of the stars headlining them. As the age of Spielberg and Lucas gave way to Michael Bay and Jerry Bruckheimer, protagonists became a less important piece of the picture and effects just kept getting bigger and bigger. Everyman actors like Tom Cruise and Harrison Ford gained prominence in the 90s, as fight scenes gave way to chases and escapes. "Independence Day" may have put Will Smith on the map, but he had to vie with the alien motherships for the audience's attention. Fifteen years later, you don't need a major A-list star to sell something like "2012" or "Avatar" anymore, and less physically imposing actors will often make the special effects look all the more impressive. The current trend is to use young, bland, almost interchangeable actors for effects-heavy B-movies like "Push" and "Jumper," and save the money for more effects shots.

There's also the demographic and cultural shifts to consider. Movies these days are aimed at a much younger crowd than they were in the 80s, especially action films. Young men have long been the most desirable audience for blockbusters, and as the mainstream has become more and more tightly focused on catering to them, the profile of movie protagonists have followed suit. The age of lead actors hasn't necessarily dropped, but they do tend to play younger than they did in the past, and having a skinnier frame helps in that department. The rise of the Internet and technology-conscious geek culture has also made athleticism a less important trait. Nerds have graduated from sidekick roles to top billing with films like "Eagle Eye" and "Spider-Man," which is being rebooted to feature an even younger cast than we had the first time around.

However, there are still plenty of older actors filling out the rosters of major action films, including Liam Neeson, Bruce Willis, and occasionally Clint Eastwood. Our most dependable stars these days are Robert Downey Jr. and Johnny Depp, both in their late forties. And there are still quite a few muscular guys like Vin Diesel and Duane "The Rock" Johnson out there who could match up to any of their counterparts of the 80s. But those two are mostly doing comedies these days. I think the real culprit is a change in the masculine ideal over the last thirty years. In fact, when you look back, beyond the 80s to older action films, it's the Stallones and the Schwarzeneggers who start to look like the odd ones out. Douglas Fairbanks Jr and Errol Flynn were no masses of brawn. And gangster films and westerns never featured ubermen. What we think of as the apex of the action film hero may have just been a passing trend.

But we haven't seen the last of them. Early tracking favors "The Expendables" over "Scott Pilgrim," and Stallone is already talking up a sequel. I figure there's room in the cinemascape for both extremes. And who knows? Maybe the pendulum will swing back the other way and bodybuilder builds will come back in style again. They're rebooting "Conan the Barbarian" soon. Maybe we'll get a new Arnold along with it.