Valerie Diaz, 15, of Virginia Beach, Virginia, had pleaded with and nagged her father, Phillip Diaz, to stop smoking, but he refused.



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"I didn't want to quit," Phillip, 36, told Yahoo! Shine. "I told her that I'm the adult and she's the kid, and I'll stop when I'm ready."



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So Valerie made a deal with her father: He would quit his 25-year, pack-a-day habit if she could get 100,000 people to like a photo of her holding a sign that read, "My daddy said if I get 100,000 likes, he'll stop smoking." Phillip added, "I only agreed because I didn't think she could rally that many people."



Yet, 30 seconds after Valerie posted the photo on Facebook, the likes started pouring in. "In four days, the photo had 130,000 likes," she told Yahoo! Shine. Dad, of course, was speechless. "I was shocked at the reach Valerie had and that so many people cared," he said. Now, obliged to meet his end of the bargain, Phillip has significantly reduced his smoking, exercises regularly, and has dropped 10 pounds in the process.



As the weather warms and shaping up becomes more of a priority, people are increasingly turning to social media platforms to get fit, whether it's posting their weight-loss progress, debating about the diet du jour, or crowdsourcing their gym snafus. In return for receiving social support and motivation, they're inspiring their followers, and everyone is staying committed to his or her fitness goals.



To track where the fittest people in the United States live, Facebook compiled user data into a list called "Facebook's Fittest Cities" and has shared it exclusively with Yahoo! Shine. Its calculations are based on user activity such as fitness-related status updates, gym check-ins, use of fitness apps, and fitness-related life events added to a person's timeline between January 1, 2013, and March 31, 2013 in cities with at least 200,000 Facebook users.



Here are the 10 fittest cities:



1. Virginia Beach, Virginia

2. Colorado Springs, Colorado

3. Austin, Texas

4. San Antonio, Texas

5. Livingston, New Jersey

6. Portland, Oregon

7. El Paso, Texas

8. Oklahoma City, Oklahoma

9. Tacoma, Washington

10. Albuquerque, New Mexico



Facebook also identified the top cities known for fitness activities:



Yoga: Austin, Texas

Running: Oklahoma City, Oklahoma

Swimming: Tucson, Arizona

Biking: Minneapolis, Minnesota

CrossFit: El Paso, Texas

Dance: Oakland, California

Triathlon: Grand Rapids, Michigan

Marathon: San Diego, California

Health Club: Wichita, Kansas



Other findings worth noting: Livingston, New Jersey, is dubbed "the weight-loss city," due to the number of people posting weight-loss milestones to their timelines. And Chicago is where people are the most adventurous when it comes to trying a new sport.



"Social media not only reveals a lot about a person's health habits; it's an essential tool for getting fit," said Kelly Olexa, founder of FitFluential, a marketing company that caters to health-oriented brands. "For one thing, it provides people with a huge support system, which is crucial when setting goals. It can also make people bolder. For example, you may not feel comfortable asking a question to a trainer at the gym, but you might ask that question to an online group that shares your struggles. Lastly, there's an accountability factor — knowing people are following your fitness journey will keep you honest."



Helping foster that group mentality are a slew of high-tech apps such as social calorie-counters, fitness trackers, and even websites that offer financial incentives to lose weight. The WiFi Body Scale tweets your weekly weight to your followers (that's good or bad, depending on whether you've cheated on your diet), the app GymPact charges people a fee for skipping their workout (those who do exercise pocket the cash), and My Fitness Pal, a calorie counter and fitness journal, doubles as a search engine for the calorie counts of almost any food and a social network for dieters. Given that almost 70 percent of adults aged 20 and older are overweight or obese, according to the Centers for Disease Control and Prevention, could social media be the answer to the national weight problem?



It was key for Brian Jacobson, 44, who shed 45 pounds from his 200-pound frame with the help of his Facebook group Oklahoma City Running Buddies. "Seven years ago, I was walking around the neighborhood with my wife when a really fit guy jogged by — that was my motivation," Jacobson told Yahoo! Shine. "I began walking daily and slowly started running." Wanting to meet people who shared his new passion for running, Jacobson launched his Facebook group. Today, the group boasts 350 people who participate in daily training sessions and races around the city. With the support of the club, Jacobson ran six marathons and is currently training for a 24-hour, 100-mile marathon. "The group has become a go-to source; the other day, someone posted about his leg injury and a doctor in the group chimed in with advice," said Jacobson.



"Talking and interacting, not just observing, is how people really get fit through social media," Kelvin Gary, owner of Body Space Fitness in New York City, told Yahoo! Shine. "Dip in, ask questions, and lend support when you can, even if it's a small gesture. I always tell my clients, 'The only bad question is the one you didn't ask.'"



Not the chatty type? Merely viewing photos on Pinterest, Flickr, or Instagram can help you to shape up. "Perusing these sites for images of healthy meals or posting photos showing off your weight loss can keep you motivated," said Olexa. That strategy worked for Dawn Turnboo, 24, a former Colorado Springs, Colorado, native who indulged in fast food twice a day and "hated" exercise. Shortly after the birth of her now-18-month-old son, Turnboo stepped out of the shower one day, caught a glimpse of her body in the mirror, and had an awakening. "I couldn't believe how heavy I had gotten. It was definitely a wakeup call," she told Yahoo! Shine. After one last meal of Chicken McNuggets and french fries, Turnboo began walking, running, and taking Zumba classes, and the pounds began melting off.



Soon after, when Turnboo's husband was deployed to Afghanistan, Facebook became the couple's main method of communication. Once a month, she posted photos of her shrinking frame. "People left so many encouraging messages that motivated me to keep going," said Turnbull. "Of course, the downside to publicly sharing my weight loss was that everyone had an opinion. I didn't let it bother me, though — if anything, it was satisfying to prove people wrong with each photo." When her husband returned home 10 months later, he was stunned by Turnboo's 72-pound weight loss.



If the idea of broadcasting your fitness goals feels uncomfortable, using social media as a third-party tool is another option. When Theodora Blanchfield, 30, a former magazine editor based in New York City, was chosen to be a bridesmaid for her friend's tropical wedding, she was terrified at the notion of wearing a bathing suit. "But I didn't want to be that girl covering up at the beach," she told Yahoo! Shine. So Blanchfield created the blog Losing Weight in the City, where she posted photos of every meal she ate. Little by little, she shared her entries on Facebook. "Knowing the world would find out if I ate pizza helped me stick to my diet." Blanchfield also began running with the help of Daily Mile, a website that tracks workouts and shares the results with a network of exercisers through status updates. Three marathons and 50 pounds later, Blanchfield reached her goal weight. And the unexpected silver lining: "I learned how to generate traffic to my blog and other digital skills, so much that I switched careers to digital strategy," she said.



Check out more social media tips to stay fit:



- "Hire" a celebrity trainer: Jillian Michaels won't make house calls, but you can reap the benefits of hiring a Hollywood trainer by following your favorites, who often post advice typically reserved for their celebrity clientele, according to Kimberly Dawn Neumann, a fitness instructor at Equinox. Don't want fitness tips cluttering your feed? Following motivational speakers such as Deepak Chopra will also keep you inspired.



- Share your progress: One recent study conducted by the University of South Carolina found that people who tweeted about their weight-loss journeys (things like, "I avoided a pastry at breakfast this morning!") lost more weight than those who didn't, thanks to the emotional support and self-esteem boost via status updates.



- Experiment on YouTube: Can't nail that squat thrust? Craving the perfect postworkout smoothie? Subscribe to a YouTube channel for instructional videos and recipes, suggested Olexa. Next step: Create your own channels and invite your friends to subscribe.



- Search for workout buddies: Check out "graph search," a search engine within Facebook that became available to all users on Monday. Typing in search terms — for example, "Running trails friends like" or "Restaurants my vegetarian friends like" — connects you to new networks of people who share your interests.



- Ban decadent food images: Photos of gooey, buttery pancakes and frosty mimosas on Instagram, Pinterest, or Facebook can throw off anyone's diet. That's because viewing images of yummy food activates the reward center of the brain, causing people to overeat, according to research published in the Journal of Neuroscience. Delete!



More on Yahoo! Shine:

How to Ditch the Sugar Habit

The New Fitness Rules

Diet Vs. Excerise: Which Matters Most?

