Take one look at the Mr. and Mrs. Muscle Beach contest and you won't be able to look away. The tanned, muscular contestants, the rhinestone-laden outfits, and the jaw-dropping barbells are just a few staples of the body-building competition, held every Fourth of July in Venice Beach, CA. It's an all-American spectacle.But don't worry: At Muscle Beach, you're invited to stare.Thankfully, for those who can't make the trek to Venice Beach, photographer Michelle Groskopf has attended and shot this event for the past three years. What keeps her coming back?The inspiring, photograph-worthy subjects who attend the competition."It has a lot of heart," Groskopf told Refinery29. "Even though it’s amateur, it’s obviously [for] people who are really, really dedicated to this sport and work really hard."The competition is open to anyone looking to strut their stuff, and the rules are simple enough: Simply walk to the centre of the stage, strike a pose facing the judges, hold it for up to 60 seconds, and then walk to the side of the stage. Competitors are divided into age, weight, and height categories. Men are judged on muscular symmetry and condition (be warned: bigger does not mean better) and stage presence; women are judged similarly, though they're expected to turn around for a "rear view" and to have satisfactory "beauty flow," which is not defined in the official rules. Oh, and regardless of gender, the rules clearly state that thongs are not allowed.Groskopf said that people come from all over the country and beyond to participate (she's met competitors from countries such as Mexico and Germany), and the ages range from teens to seniors. The best part? "Everyone seems to know each other," Groskopf said.The photos Groskopf takes manage to capture all of the hard work and passion that goes into the competition— beyond the pageantry, it's clear that these people take their lifestyle very seriously (and they have the muscles to prove it)."I think a lot of people go just to laugh at the fake-tan spray and the grease and the bedazzled barbells and stuff like that, but it’s a lot of work, and it’s really moving to see that," Groskopf said. "The body is an amazing thing."This year, Groskopf told us she decided to focus her work on the female competitors. There aren't many of them, she said, but the ones that are there are "a sight to behold."Want proof?Click ahead to see Groskopf's behind-the-scenes photos of the competition, along with her thoughts on the women of Mr. and Mrs. Muscle Beach.