If you took a poll on the street 95 percent of people, once they stopped snickering, would have no idea what a fartlek is, running coach Ann Alyanak told me when I asked her where they’d been all my life.

Alyanak is part of the Run S.M.A.R.T. Project based in Arizona. An elite runner herself, she coaches up to 11 runners at a time using online tools and weekly phone calls. I’d been training with her for only two weeks when “fartlek” appeared on my training calendar.

I had already searched for a definition of “fartleks” during our initial telephone conversation because Alyanak wanted to know how I felt about doing them.

Now that I’ve experienced my first fartlek workout, I’m smitten.

“Fartlek” is Swedish and literally means speed play. According to the online definition, it’s a “system of training for distance runners in which the terrain and pace are continually varied to eliminate boredom and enhance psychological aspects of conditioning.”

Alyanak said fartleks became popular during the big running boom in the 1970s.

“I think elites brought them over from Europe, but over time they’ve evolved into regular training plans,” she said.

For my workout on the track, Alyanak had me run an easy mile and then build into my run eight repetitions of fartleks, running one minute hard and one minute easy and then finishing up with a mile at an easy pace.

My good friend Neile joined me early in the morning at our neighborhood track, and both of us felt a rush that stayed with us all day. We also had another friend with us who carried the stopwatch and told us when to speed up and when to slow down, at times yelling across the track. For most of the 35 minutes or so, we ran in a warm downpour, which gave the workout another element of fun.

I asked Alyanak about the difference between fartleks and intervals, because it seemed to me that that’s what Neile and I were doing.

“Fartleks are more unstructured than intervals, and you can do them inside the run itself,” she answered. “You have a little more freedom versus a very structured interval workout.”

There are a lot of different ways to do fartleks, she said. For example, you don’t have to set a distance — you can do them between two telephone poles, or if you’re on a track you can run hard or run easy.

Ultimately, we ended up doing five repetitions of one minute hard and one minute easy and then three repetitions of 30 seconds hard and one minute easy. For the last three reps, on a scale of 1 to 10, we were pushing ourselves to get to 7 for the hard runs and came back down to a 2 or 3 for the easy runs.

That’s another reason why Alyanak likes fartleks — you’re running the whole time. With intervals, often you’re sprinting and then resting.

She said fartleks are particularly good for new runners, which is why she picked them for me; I’ve been running for only a year, and I’ve just now begun to train for my first marathon.

“I prefer them when just getting started because you can go by your own effort and not try an exact pace and not outrun yourself,” she said. “You can stay within an effort zone you can achieve but still push yourself hard on one day and go easy on the next.”

But they’re great anytime in your training because you can run easier or you can really hammer them, depending on what you want to do with the day’s workout. And that’s where play comes into it; they’re fun.

There are also weight-loss benefits to fartleks, Alyanak noted, because you burn more calories when you increase your heart rate during exercise. Lots of studies show you burn more calories even after your workout if your heart rate has been elevated.

Even though we felt as if our hearts were in our throats, Neile and I enjoyed our fartlek workout so much we thought we might try it again the next morning. But Alyanak cautioned against doing them on consecutive days.

You should go easy the day after you push hard, she said. Especially since she’s got me doing increasingly long runs once a week, I’m taking her advice.

Carolee Belkin Walker is a federal bureaucrat, blogger and freelancer. She shares her fitness adventures on her blog, www.bethedog.ninja. The views expressed here are those of Walker and not those of the U.S. government.