If your friend who’s running the Marine Corps Marathon posts to Facebook in the middle of the race, don’t be that impressed.

Sure, running 26.2 miles is hard, but it’s not tough for participants to multitask when they’ve signed up for the free social media messaging service debuting at Sunday’s event.

The idea is that at every 10k, the timing system will generate an automatic message for your followers on Facebook or Twitter, so they can cheer you on throughout the course, whether they’re standing at the finish line or chilling on the couch at home.

It’s one of the latest gee-whiz advancements in runner-tracking technology within the past decade. It started with text messages of finish times to runners and their supporters, evolved into more sophisticated systems that relayed the pace of participants at several points during the race and has now reached social media platforms, along with mobile phone apps and GPS devices that allow spectators to follow every step of the way.

“The potential is huge. It’s turned running from an isolated event into an interactive one,” says Alexandria’s Ray Maker, a 29-year-old triathlete who blogs at Dcrainmaker.com.

Runners make their way through the route for the 2009 Marine Corps Marathon. (Toni L. Sandys/THE WASHINGTON POST)

Marine Corps Marathon marketing and sponsorship manager Marc Goldman proudly notes that the organization strives to get ahead of the pack when it comes to innovation. “We’re the biggest coming-out party for a lot of this stuff,” he says. One tech trick on the horizon is the ability to send race photography immediately to runners’ social media pages, so their fans can get the sights as well as the stats.

But first, current race technology needs to get over a few hurdles. A particularly nagging problem has been how quickly the information is delivered. “Text messaging has not been an exact science in the past,” Goldman says. That’s not just an MCM issue. Any regular racer could tell you that it’s never guaranteed that race pace texts and e-mails (or these newfangled Facebook and Twitter messages) will show up on time — if at all.

In fact, Xact, the company that’s scheduled to make the magic happen at the MCM, was in charge of a similar service at the Baltimore Running Festival on Oct. 15. At the pre-race expo just after signing up for text alerts for his family, Eric Hayden, 29, of Los Angeles, had high hopes for accuracy. “I’ve used tracking at all of my past marathons, but it’s never been real time enough. Usually it’s been delayed significantly,” he said. This time, it was worse: No one got a single message.

At least that was a free service that didn’t work. Last year, the MCM touted the RaceMate app ($1.99), which was supposed to allow spectators to track their runners live. According to Goldman, the service was completely overwhelmed by the amount of data and just plain didn’t work.

Although the angry app purchasers had their money refunded, it’s not so shocking that there’s no updated version for 2011. And Goldman takes great pains to explain that the free mobile locator map they’re launching this year that directs spectators to mile markers, aid stations and other key points on the course is not an app.

Not that apps are unwelcome at the MCM. Given the spotty reliability of data from events, plenty of runners are taking tracking into their own hands — or rather, pockets. Any number of free smartphone apps, including Loopt, Google Latitude and Find My Friend, allow users to show their locations in real time to a select group of people. Even better are the apps specifically designed for athletic purposes, such as Endomondo (free), MapMyFitness (free) and RunKeeper (free, but charges a fee to upgrade to elite status for live tracking).

In addition to tracking, several apps will allow you to link to social networks and schedule posts as often as you want, as opposed to the race course technology, which only updates when runners cross a timing mat. MapMyFitness co-founder Robin Thurston says the technology will soon be able to turn friends’ Facebook replies into audio files. “A voice will come across the headphones over your music, ‘Go Robin, you can do it, Mile 16!’ ” Thurston says. (That function's already available on another app, Runmeter.)

There are, however, several limitations with phones, starting with battery life. Keeping these apps on can sap power fast, especially if Wi-Fi is on and you’re using it for other purposes, such as listening to music.

Other issues include connectivity and the sheer size or weight of your phone and its durability. Companies have developed tiny GPS trackers that can solve these problems — for a price. Maker has been relying on the new Garmin GTU 10 for his races. “It’s like having a stick of gum in my pocket,” he says. Another option is My Athlete Live, which runners can rent. The slogan: “You don’t need it, your friends and family need it.”

So what do runners need? “Simplicity,” Maker says. “I want to be able to run and not worry about technology.”

Keeping up with the race

It’s called “The People’s Marathon,” but the 36th Marine Corps Marathon is also welcoming computers and smartphones to participate. Here are three ways technology’s taking a place in this year’s race:

Social media messaging. Runners can register at Marinemarathon.com for a service that reports their 10k, 20k, 30k, 40k and finish times to their Facebook or Twitter accounts. You can also send updates to a select group via text messages or e-mail.

#36thMCM. Update the race community by using this hash tag on Twitter. Your tweets will be featured on large screens at the pre-race expo, the Hyatt Regency on Capitol Hill (the race headquarters hotel) and the finish line.

Mobile locator map. Lost at the race? Put Mcmlocator.com into the web browser on your iPhone or Android to get directions to mile markers, water points and other race landmarks.