Personal trainers were once considered luxuries reserved for athletes, movie stars and the well off — but technology has changed that. These days you can hire, for the fraction of the cost, a virtual trainer to help you work out in the comfort of your own home.

A trainer might design a workout regimen just for you and offer encouragement over live video. Or you can take a class and follow a trainer via live or on-demand video streaming.

Two years ago, Meghan Houtsma was looking online for a virtual trainer to help her daughter shed some weight she’d gained at college. It didn’t take long for Meghan to realize the same idea might work for her.

“We live in Southwest Kansas where there are significantly more cows than people and where access to a certified personal trainer is extremely limited,” Meghan said. “I would have to drive 65 miles to get to a gym with more than a couple of treadmills and a weight machine, not to mention a trainer.”

What she loves about having a virtual trainer is having someone else to be accountable to, which helps her stick with her exercise routine. “I also love it that I can do workouts anytime and anyplace,” she says. “I have two young sons and need to get my workouts done early in the morning, or they probably won’t happen.”

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What does it cost?

Fitness organizations back the trend toward online training. "When it was first introduced, online personal training was considered a poor substitute for working with a real live trainer," according to the website of the American Council on Exercise (ACE), a fitness education and certification organization. But with improvement in apps and video conferencing, ACE officials say, "Online personal training has gone mainstream."

On the Internet, virtual trainers abound, so you can comparison shop. A virtual trainer can cost as little as $20 a month vs. $70 to $100 an hour for an in-person trainer. You can find a virtual trainer who’s local or who lives in another state or even another country, and access workout regimens on demand or through game consoles. And your virtual trainer can tailor your workouts to fit you.

Companies such as VirtuFit.net, BestBodyFitness and MyBOD offer personal training workouts for $27 to $60 a session. Organizations such as DanceFIT and Wello offer monthly memberships for $80 to $99 for 10 group classes per month, and some app-based programs are still cheaper: Gym America offers interactive workout and diet plans for $7 a month or $50 for six months, according to costhelper.com. On Skype and Google+, classes can include up to nine participants plus the instructor. You can see each person (unless you or they disable the camera), allowing the instructor to cue participants individually.

What to look for

Here are some things to consider if you’re looking for a virtual trainer, courtesy of the American Council on Exercise, a nonprofit fitness, education and certification organization, along with the online fitness website iBodyFit and the virtual trainer website I Think Fit.

Look for a trainer you feel in sync with. Google "virtual fitness trainer" and "online fitness trainer" to find a possible match, but do your homework. Ask to have a Skype conversation and to pay for an introductory class, if possible, before signing up for a full session.

Know your level of motivation. The best virtual trainers offer the right mix of affordability, personalized programs, availability, variety, convenience and accountability, according to iBodyFit. Still, clients have to supply their own desire. “If you are not self-motivated, it’s easier to have a trainer right there in front of you,” said Franklin Antoian, founder of iBodyFit and author of "The Fit Executive."

Check qualifications. Find a personal trainer whose certification is accredited by National Commission for Certifying Agencies (NCAA), which lists the organizations and certifications it accepts on its website. These include Certified Personal Trainer certificates from the ACE, the American College of Sports Medicine (ACSM) and the National Strength and Conditioning Association (NCSA). Double-check with the certifying agency. Ask about experience as well. If the virtual trainer seems too hard-sell, experts say, look for someone else.

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Seek out a personalized program. “A good trainer will take into account your body type, size and goals and assign you a program that is designed specifically for you,” says Sean Hartley, owner of iThinkFit. Many virtual trainer programs, he says, “are not even run by trainers and just give everyone the same program regardless of any personal factors.”

Get on the same page. Personal trainer Jason Helmes of Anyman Fitness in Brooklyn, writing in an online personal trainer forum, recommends that after you discuss your goals, you and the trainer establish:

  • How often you’re expected to contact the trainer
  • How prompt the response time will be
  • What information you should have for “checkpoints”
  • How accurate your measurements should be
  • How many emails a week are acceptable

Start small and work up. Look for a personal trainer who doesn't confuse soreness with progress, fitness coaches advise. If you’re pregnant or have any medical conditions, get a check-up and talk with your doctor before beginning a new exercise routine. For healthy adults, the Department of Health and Human Services recommends at least 150 minutes of moderate aerobic activity (or 75 minutes of vigorous aerobic activity) a week, plus strength training at least twice a week. (You don’t have to do all that inside your house, of course: You can report your walks or jogs outside to your virtual trainer as well.)

Consider virtual training apps for your smartphone. If money is an issue or you prefer less structure, check out the bounty of virtual training apps that can design and monitor your workouts, such as GAINFitness and Nike Training Club. Some include a customizable workout calendar, track your performance history and calories burned and send notifications if you miss a scheduled workout.

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Brian Johns is a freelance writer and consultant who has worked as a staff reporter for the Journal of Commerce, the Oakland Tribune and the Lexington Herald-Leader, and is a volunteer with the National Association of Black Journalists.