How do you get 1.5 million people to drop and give you 15 sit-ups, 5 crunches, 5 leg raises and a 10-second plank?
Photo credit: Blend Images - JGI / Jamie Grill / Brand X Pictures / Getty Images

Create a Facebook event, promise killer abs after 30 days, and then sit back and wait for the magic to happen.

Robyn Mendenhall Gardner says she created the "30 Day Ab Challenge [Facebook event] for those who need some motivation like me," which is the actual title of this event. The event is a 30-day-long challenge of progressively increasing abdominal exercises that she found online and decided to turn into an event to motivate herself by involving others.

Apparently 1.5 million of us need motivation like Robyn does, because that's how many people have "joined" her event (300,000 have joined since I started researching this story 12 hours ago).

This kickoff to kickin' abs is visible only to friends of guests, but even with those parameters, the guest count is high enough to raise the question: How long until Kevin Bacon joins too?

Get it!^

Download the 30-day ab challenge calendar

Just a way to sell Plexus?

Gardner's page spotlights that she uses Plexus products (and says she lost 58 pounds in nine months) and in fact now sells them, but she's quick to say that's not why she created the event.

"I am a Momma of 8 who has struggled with overeating and bad food choices," she says. ... "Its [sic] important that you all know I started this group for my own motivation because after having children my belly wasn't appealing to me and I thought this would be a great idea.

"I never expected this group to grow like it has nor am I trying to use this as an avenue to push my Plexus products. I simply want everyone who struggles with exercising and needs a little motivation and inspiration to join me on my journey."

After boot camp, why not?

After noticing several Facebook friends "liking" the event, Tiffany Mason's interest was piqued. Fresh off her first month of boot camp, the 39-year-old vice president at a FORTUNE 100 company says she was drawn to the gradually increased intensity — as well as the brief amount of time the exercises should take each day.

"I think this challenge, on top of boot camp, will really amp things up," shares the mom of two, ages 8 and 5. "And what better time of year to feel toned. I can do anything for a month, so I will definitely complete it. However, it might come with a lot of whining and plenty of Aleve!"

Her aspirations are more noble than mine. I clicked "join" primarily because I've always believed that simply stating I will, at some point, one day, do abs exercises will miraculously whittle 3 inches from my waist. No?

Gardner's goals

"What I'd like to happen (and what will happen will probably be very different) would be for everyone to post their comments of completion, or post pics or a video of parts of their workout or the whole workout, to the wall to help keep everyone motivated and to also try and hold everyone accountable," Gardner shares.

Now, if someone threatened to post pictures of me, that would probably motivate me even more than the urban legend clown chasing me with a butcher knife.

"I can't come to everyone's home or place of work and make you do these so we all are going to have to work together to try and complete this entire challenge."

Quit whining, and be safe

Sounds simple, right? Absolutely, unless you're the type of person who can't help but flip to the back of a book before reading it. I peeked: Day 30 of the ab challenge looks absolutely grueling — until I remind myself that the exercises will build in number slowly. Then I read Gardner's note that participants can do each day's routine twice.

Just reading that tweaks a muscle in my back. Which leads to the next cool thing about this challenge: Gardner has posted video links demonstrating how to perform each of the four exercises safely and most effectively. I like that. I'm still nervous to get started, but I like the support.

All my reluctance and whining is exactly what Gardner strives to avoid. Her one steadfast rule: "No negativity!"

Online cheerleader

Truthfully, her energy (even just in print!) is infectious: "You can do this from home or your office at your own convenience," she writes. "You can do … each days [sic] challenge once a day or if you really want to get max results you can do it twice a day! Believe in yourself, you can do this! If I can do it, YOU CAN DO IT! Always drink lots of water to stay hydrated! MOST IMPORTANTLY: NO NEGATIVITY!"

After all, we're each accountable to ourselves, doing these exercises in the privacy of our own home or, more awkwardly, in our 6-foot-by-6-foot cubicle while passers-by do a double take. "Hey, Larry! Just wrapping up a plank, here! Lunch in a few?"

So, what if we all showed up?

But the degree of anonymity is working, and Gardner must be relieved she doesn't have to find accommodations for all attendees. Especially because of the way people never RSVP and just show up to an event. (I'm talking to you, father of 12 who told my husband you're coming to our party Sunday but still haven't clicked "yes" on the Evite.)

With 19,000 "maybes," this event could fill more than 45 Fenway Parks. Or imagine this: If everyone who says they're attending then showed up at world-famous Gold's Gym in Venice, California, the crowd would be 37 times the entire population of Venice, California. Someone would have to buy a ton of yoga mats, and fast.

And probably a vat or two of air freshener, just in case.

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