There's a common belief that achieving most goals is a marathon, not a sprint. For the athletes in Row Hard No Excuses, their shared aspiration makes a marathon look like a gentle morning walk.

These people, determined beyond description, form two-person rowing teams for The Atlantic Rowing Challenge, a genteel unassuming name for a brutal competition. In short, it's a 3000-mile race that's seems virtually impossible. From the Canary Islands to Barbados, rowers do nothing but pull themselves across the sea, unaided, every single day. For the winners, it takes usually about 5 to 6 weeks -- for everyone else, well, good luck.

Row Hard is director Luke Wolbach's document of the race, with a loose focus on one particular team: a pair of guys who, at ages 51 and 41, enter as the race's oldest-ever participants. Although the real action and terror occur out in the open water, Wolbach spends time to generate some backstory on these guys in a valuable but forced attempt.

John Zeigler and Tom Mailhot are presented as your typical American Everymen, right down to their masculine insecurities and father issues. Like many, they wonder if some level of overachievement will help exorcise their demons, even if they're not sure what those demons are. What makes them different is how far they'll go to see a dream through. The entry fee to race is $150,000. The payoff? Nothing but personal pride.

So why do they do it? Why do these teams suffer? That's like asking an ambitious climber why he wants to tackle Everest -- and there are obvious similarities between Row Hard and the film Everest -- but it doesn't mean we're not intrigued. If Wolbach could've dug deeper into what drives the insanity, Row Hard could have been a fascinating combination of physical prowess and mental madness. But the athletes' emotions -- and in turn, themselves -- are kept at a distance.

The focus then becomes the minutiae of the race itself, and that's generally enough to hold our interest. There's constant danger, sickening loneliness, one- and two-person mind games… not to mention horrific butt rashes and hand sores.

Like a documentary filmmaker specializing in history, Wolbach tells the story more as an editor than a chronicler. Most of the film's footage was shot and delivered by its stars, the teams who turned the cameras on themselves throughout their grueling expedition. Through these "video diaries at sea," as the filmmakers call them, we see the athletes bitching about one another, rowing naked (is that more comfortable?), and questioning just about everything. Wolbach's talent is in packaging the rowers' disgust and elation, and retaining a dramatic storyline the whole way.

If you don't know anything about the race, there are some satisfying surprises, especially in a skillful coda that says a lot about the rowing community. But the overall delivery is just off, lacking the tight drama and polish the race -- and racers -- deserve. As good as the document is, there's some potential there that's not being tapped as our protagonists, trying to recognize their own potential, meet their destiny.