STEVE INSKEEP, HOST:
A, I know we're busy with a show...
A MARTÍNEZ, HOST:
Yeah.
INSKEEP: ...Here and...
MARTÍNEZ: Yeah.
INSKEEP: ...Everything, but I got a question for you.
MARTÍNEZ: Yeah.
INSKEEP: You run. I know I run.
MARTÍNEZ: Yeah.
INSKEEP: But have you ever lifted weights?
MARTÍNEZ: That you have to ask, Steve, means I'm not lifting enough weights.
INSKEEP: (Laughter).
MARTÍNEZ: So I'm going to do some bicep curls and cry.
INSKEEP: (Laughter) I've seen your biceps. I think you do something. And there is evidence of benefits.
MARTÍNEZ: Something? That's it? Oh, my God.
INSKEEP: Well, we'll be more specific later. Time is short.
MARTÍNEZ: All right. All right. All right.
INSKEEP: Anyway, turns out that strength training is good for your metabolism, your bones - even your brain. Resistance training is what it's called. NPR health correspondent Will Stone has some good news. Research indicates it will not take long for A to see the benefits.
WILL STONE, BYLINE: Lack of time. That's one of the main reasons people don't exercise, and it's especially true for resistance training. David Behm is an exercise physiologist at Memorial University of Newfoundland in Canada. He says people have a perception you need to do these intricate routines that eat up hours and hours.
DAVID BEHM: They've been told, I got to go in. I got to do three sets of 10 for my shoulders, for my chest, for my back, for my quadriceps, for my hamstrings. My God, I'm going to be in there for an hour and a half. And then I got to take a shower afterwards.
STONE: Sure, you can do this. But if your goal is generally to build some muscle and get the health benefits, Behm and others in his field have another suggestion - aim for what they call the minimum dose.
BEHM: So what can I get away with?
STONE: For example, if you're brand new, Behm says the evidence shows you can start with just one workout a week.
BEHM: For the first three months, for a person who hasn't worked out before, once a week, one set, six to 12 reps sort of thing.
STONE: Ideally, you're doing a handful of what are known as multijoint exercises - one set of squats, a set of chest presses, rows and so on. You can also do variations of them on machines.
BEHM: If you have more time and you want to get better, well, then work out twice a week. Or maybe, you know, after 12 weeks, move to two sets.
STONE: The key here is that you do need to push your muscles so they're taxed and struggling at the end of the set.
JAMES STEELE: It should feel like it's hard work to actually try and move that weight.
STONE: That's James Steele, a researcher based in the U.K., and he also supports a bite-sized approach. One of his studies followed nearly 15,000 people for up to seven years. Their weekly time commitment? Twenty minutes.
STEELE: They trained, like, once a week. They did a handful of exercises, and that was it.
STONE: The typical participant got anywhere from 30% to 50% stronger. Much of those gains happened in the first year and then were maintained throughout the study. Now, if you do spend more time working out, you will build more muscle. But Brad Schoenfeld says the return on investment starts to go down pretty quickly. Schoenfeld is an exercise scientist at Lehman College in the Bronx.
BRAD SCHOENFELD: It's not linear, where it just goes up and up. You see the biggest increase in the first few sets, and then you see it leveling off.
STONE: All this depends on your goals. A minimalist approach may not get you the most possible strength and muscle, but Schoenfeld says it can go a long way. His advice is to try for two workouts a week if possible.
SCHOENFELD: We're talking an hour to an hour and a half a week. You can make very good gains and really see benefits on all the health markers.
STONE: And it's all the more important as you age. Your body naturally starts to lose muscle, but you can work to counteract that. And research finds you can still make progress well into your 60s, 70s and even 80s.
Will Stone, NPR News.
INSKEEP: OK. Will is going to flex more knowledge about the science of strength training in a new Life Kit newsletter. It's about how to start a strength training routine. You can sign up at npr.org/stronger.
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