How Heavy Should You Lift? Good news for lightweights!

One of Shine's most entertaining fitness posts ever was fired off as a letter to Gwyneth Paltrow's trainer about how much weight women should lift. "Wow, I just saw the quote of yours: No woman should lift more than 3 pounds," Fitness Fixation blogged. "That has to be a joke, right? ...Somebody please tell me I'm just having a bad dream."

FF, you are having a bad dream. And I'm having a great one, according to a study that came out this week from McMaster University in Ontario. Not that we're arguing; just continuing the debate about how much a woman must lift to get fit.

For years, it's true, the gym gospel has been: Lift heavy or you might as well be painting your nails. So the new findings are making news. In short, researchers showed that you can, indeed, build muscle by using light weights, as long as you do enough reps. Measuring muscle protein synthesis, they conclude that "low-load contractions peformed with numerous repetitions or high-load contractions performed with fewer reptitions will result in similar training induced gains in muscle hypertrophy [increase in volume] ... or even superior gains."

As someone who hates heaving and ho-ing, unless it's a cranky child or a '60s vintage leopard settee up the stairs from the flea market, I feel this is cause to celebrate. In fact, as soon I heard about the study, I had to get my hands on it and do a bench press.

But seriously, how does the new science translate into looking knockout in a bikini or kicking butt in a soccer game? I asked three trainers to read the study and advise:

Light Weights

EXAMPLE: 3-5 pound weights doing 25 reps

WHO SHOULD DO IT? "Women who want to tone, lengthen, and get definition," says Jenn Burke, personal training manager for one of the Crunch gyms in Manhattan. Another New York trainer,Michael Gonzalez-Wallace, who created the Super Body, Super Brain program, is convinced this is best way for anyone to condition the whole body, because it strengthens the joints while avoiding risk of injury. "And the muscles grow very long and lean because you're creating new muscle protein every time you're contracting."

THE THEORY:This kind of workout primarily trains your "slow twitch fibers," which are good for endurance. What the study showed for the first time, explains Gonzalez-Wallace, is that as you keep lifting, you also start recruiting the "fast twitch" fibers-the ones you use pumping heavy poundage, and the ones that build muscle. ("You can test it out yourself by doing a shoulder lateral raise with two small water bottles. Do 25 reps, or as many as you can, and the weight starts feeling like 30 pounds.") For safety, he says, the place you should stop, "is right before you can't lift another rep."

Heavy Weights

EXAMPLE 10-25 pounds but only 6 to 10 reps

BEST FOR: Women who want to build size. This kind of training also helps you in sports where you need to be strong and fast.

THE THEORY: "Heavy loads recruit your fast twitch fibers and give you power and size," says The Hollywood Trainer, Jeanette Jenkins, whose new DVD is "Blast the Belly Fat." In a typical training program, you lift as much as you can, and when that becomes easy, you increase the weight and lower the reps.

Mix it Up

EXAMPLE: Drop sets, in which you lift 10 to 15 reps, then drop the weight 50 percent and continue to 25 reps

BEST FOR: Women with mesomorph bodies, like Serena Williams or Janet Jackson, says Jenkins, who is also built this way. "We're geneticially gifted with muscle, and we gain size easily." Unless you want to gain bulk, heavy lifting may be too much. On the other hand, says Jenkins, "I find that the light lifting doesn't cause enough of a change in the body."

THE THEORY: There are many ways to mix it up. Burke takes her students through a light, medium, and heavy phase, and then has them repeat the cycle. "You don't want to stay in the same phase for more than 4 weeks," she says. Jenkins loves drop sets along with yoga or lengthening work because, she says they recruit all types of muscle fibers. "They're great for anyone who wants to get ripped."


* Always check with a doctor before taking on a weight lifting program, especially if you have any injuries or medical conditions.


Hey ladies, what's your take on resistance training? Hate it? Love it? Light or heavy?


For more great trainer tips

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