Explaining the latest fitness trend: NPR

MICHEL MARTIN, HOST:

Hey, A.

And Martínez, host:

Yes.

MARTIN: Did you exercise this weekend? How did it go?

MARTÍNEZ: I have two. One was easy, and the second was that I challenged myself.

MARTIN: (Laughter) Atrocious. ALL RIGHT.

MARTÍNEZ: Yes. Yeah.

MARTIN: Well, in the world of professional sports and fitness, people talk about training zones as sort of a spectrum of intensity from light exercise to really intense exercise – it sounds like that’s you. For more casual athletes, one zone in particular is getting a lot of attention: Zone 2. NPR’s Will Stone has this report.

WILL STONE, BYLINE: Ask Carl Foster about the merits of Zone 2 training, and first, you’ll get a question.

CARL FOSTER: Which zone 2 are you talking about?

STONE: The answer may depend on the sport, the country or even the type of researcher you are. For example, Foster is an exercise physiologist.

FOSTER: And we tend to think in terms of just three zones. And zone 2 is sort of the middle zone, and it’s sporty.

PIERRE: Hard. However, you are not entirely at your peak. And Foster says there are thresholds that you can clearly measure with blood tests and breathing habits. But if you encounter Zone 2 discussions these days, chances are it’s not this intensity that people are talking about. Instead, they describe something more relaxing – something you can do for longer periods of time.

FOSTER: And zone 2 is you can do a lot of training and you can get a lot of benefit with very minimal pain. And so it’s attractive.

PIERRE: Here, zone 2 is at the lower end of a scale of five or six zones, maybe even more. Stephen Seiler is a practicing researcher at the University of Agder in Norway. He says professional cycling has fueled the current Zone 2 phenomenon. Because athletes go on long training rides, they need to refine their low-intensity work. But translating all this to the general public and to different endurance sports can be tricky.

STEPHEN SEILER: There is no magic zone. That’s what the research tells us.

STONE: Unlike elite athletes, the average runner doesn’t necessarily have this wide range of lower intensity efforts.

SEILER: It can be very narrow. I know through experience I got back into running and felt like, oh, my God, I can barely run before it starts to feel like it’s no fun.

STONE: Seiler popularized polarized training. The idea here is that the majority of your endurance training should take place in this easier, more sustainable area, then a smaller percentage at a higher intensity. This is based on research carried out with top athletes. But Seiler says the principle is useful for all of us because…

SEILER: The most common mistake is that everyone ends up – their workouts regress towards the middle. And there’s nothing wrong with that kind of training, but if you’re doing it every day, if you’re doing it every time you train, then you get stagnant pretty quickly.

STONE: So to avoid falling into that pattern, he says there are some simple tricks to finding that Zone 2 space. Basically, you can have a conversation. Your heart rate stabilizes after 10-15 minutes and you can eat fairly quickly after training.

SEILER: And then, yeah, other days you’re going to train harder, but you’re putting together – you’re putting together a training orchestra that’s not just one note.

STONE: Now, some of the recent excitement around Zone 2 is based on claims that it has particular metabolic benefits, including burning fat, which makes it better. Brendon Gurd, of Queen’s University in Canada, says the data doesn’t really support this hypothesis.

BRENDON GURD: If you just want to get a little fitter and be active and healthier, zone 2 is great, but if you want to kind of maximize your four hours a week, the best four hours are probably going to be high intensity.

STONE: Billy Sperlich of the University of Würzburg in Germany agrees. If you’re just looking for a return on investment for cardiovascular benefits, energy burning and high intensity win out. But we can’t do that all the time. And he also sees the current interest in the Zone 2 concept as part of a larger back-and-forth in the fitness world.

BILLY SPERLICH: We had a very, very strong, I would say, hype about high-intensity exercise, and all of a sudden, oops, it’s all back to low-intensity exercise. The answers were endurance athletes. It’s a mix, basically.

STONE: And while there are different schools of thought on the exact combination, zone 2 proponents point out another benefit: When a workout isn’t too brutal, you’re more likely to do it again.

Will Stone. NPR News.

(SOUNDBITE OF KAYTRANADA’S “WEIGHT OFF (FEAT. BADBADNOTGOOD)”)

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