A Black runner named Shareef (Tavius Cortez) is part of the most sardonic, long-running gag in the film — that his training runs are constantly interrupted by local police who inevitably chase him. 

Then there’s maybe the most honest subject among them — Emilou (Kimia Behpoornia), who quits before she even starts. Her marathons then tend toward binge watching TV. Or, as she says at one point, “I’’ll tell you what’s a marathon – scrolling through your whole Facebook timeline.”

The directors say about a third of the dialog is improvised (actually, according to the press kit, Strausbaugh puts it as “75 percent scripted, 35 percent improvised”). And Behpoornia, like many of the cast members, come from improv groups.

Most were culled from the underutilized Las Vegas pool of performers, in comedy groups, Blue Man Group, Cirque du Soleil or the cabaret production of “Absinthe” (described as “Cirque du Soleil as channel through The Rocky Horror Picture Show”). 

The only one of them that doesn’t work quite as well is Jimmy Slonina’s shoe salesman turned race organizer — with his glasses, short sleeve dress shirt and clip-on tie, he’s a little too much in the cliched Wally Cox/ “Office Space” nerd role and doesn’t need that well-worn persona to deliver his lines.

Vegas is the setting as well, though the cameras stay away from the Strip and other familiar landmarks, sticking to the suburbs at least until the race is organized (crazily) in the nearby desert. 

Organized in chunks of time as the marathon approaches, we can see each of the character’s progression (or, more often, regressIon). And the race itself is a mess of blow up starting gates, cynical water-givers and en route accidents.

Other than a couple of mentions of the Boston Marathon bombing (too soon?), “Marathon” is a pleasant enough romp, something that strives, from its deadpan delivery to be a low key entertainment. Its fun is even more enjoyable indoors, watching in air conditioning, like the slacker ex-runner Emilou.

If it won’t win awards, at least they have all those second-hand participation medals to spread around.

“Marathon” is available on video on demand.