Pejorative gym rat slang for the people who invade gyms at or around the 1st of January of every year. They are a bane and a blessing to the physical fitness community.
Sir on 4chan's /fit board does a cartoon every year about resolutioners, his expy cartoon self dealing with any of a number of inconveniences and weirdnesses. It's usually chock full of memes and has a lot of inside jokes.
The bane deals with the fact that gyms become very very crowded. With most gyms having one squat rack and one or two bench press benches, it is a nuisance to have a sudden influx of people who want to use these, poorly. Given they rarely know gym etiquette it means that your time there becomes full of small annoyances here and there as well.
A gym at the best of times is full of all kinds of interesting characters. You can practically tell when people started lifting by their attire - including "the old guys". These legends who walk around the locker room with their towels over their shoulder rather than around their waist swinging their long-hanging testicles and shocks of white pubic hair and in the gym wear Wal-Mart white T-shirts and basic gym shorts. The ones who dry out their remaining head hair but also their buttcracks and pubes with the gym's hair dryers by standing in a very exhibitionist fashion while blowing air hither and yon. You also have the black guys who started lifting in the 1980s who are now in their 50s or older and look like extras out of Michael Jackson's "Beat It" video with do-rags and mesh shirts over their tank-tops. You have your ex-football high school players in their school shirts, and your earnest young guys who sport the absolute latest gear from UnderArmour and Nike and their Beats headphones.
The relative popularity of women entering gyms leads to a small subculture of Smith Machine squatters working hard on developing rounded muscular buttocks and tight hips, clustered around the leg-spreading abductor machines.
You also have the intense powerlifter and/or weightlifter crowd dragging in Marine canvas duffel bags full of thick, long industrial strength rubber bands with 150lb of pull and several feet of heavy chromed chains which they attach to the bars for their Westside or 5/3/1 routines, hiding their chalk use like schoolchildren trying to sneak a smoke behind the bleachers.
And of course you have the odd purveyor of gym fuckery that cannot and will not simply work out or train in any normal way - usually wearing an oxygen-choking altitude simulator mask while standing on a wobble board doing lateral raises standing on one leg. Also included in this gym crowd are old Asian guys who look at a pec-flye machine and think to stand in some wide-squatting kung-fu stance and do some kind of weighted t'ai chi move with it, eschewing the seat and standing to one side, hauling on one handle ballistically.
The long and the short of it is that any gym floor is a delicately balanced ecosystem of various disparate groups who are there for various purposes, occasionally meeting at the gym's literal watering hole with their flasks and their gallon-jug water bottles at the fountain.
This gets completely fucked when the newbs come in. They're there in their Christmas-gifted tank tops and track pants, new Nike Metcons and spotless mesh-backed "bitch mitts", those fingerless padded gloves people not in the know think they have to wear. Their mere presence also excites the people who work there, who get the occasional $29 a session "spiff" to show these folks how to raise and lower the seat on the bicep machine, meaning that rather than sitting in a corner glumly texting like they do the rest of the year these would be "personal trainers" are suddenly swarming through the floor like fruit flies as well. And like a tourist standing in the middle of a busy New York City street staring upwards at the sights interrupting the pedestrian traffic flow, they're a reason some people plan their "off week" around the New Year.
You can't really be impolite to resolutioners because we ALL started somewhere and showed up to a gym like that, intimidated, fat, scrawny, weak, scared to show our faces. And we're usually nice and helpful to them, stopping them from doing something really dangerous that will snap their spine, but we will judge their response.
But it's nice when it gets to the third week of January and there's a real fuckin' dropoff in attendance, and relative calm returns to the gym floor.
Here's the blessing. Since the gym owner has raked in a large number of "sign up fees" that are nonrefundable, that $99 a person and the three or four months auto-debit that they'll contribute before sheepishly cancelling it adds enough to the coffers that there's usually some new plates or repaired equipment out of it and the gym stays open for another year.
If you are ever looking for good deals on exercise equipment, look at Craigslist in February, and note the "want this out of my living room" prices on treadmills and basic bench sets usually shown in a photo with clothes hanging off them and boxes parked on them.
It is all part of the cycle of gym life - like the yearly brush fire that puts nitrogen back in the soil. Mind you, some people stick around, find their tribe in the gym, and stick with it. And that's great too.