It might be time for workout warriors to stack a couple more weight plates onto the pile. A recent study showed that many inexperienced weightlifters don't come close to pumping enough iron to change the shape of their muscles, or really get any benefit at all.
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The study, done by exercise physiology professor Stephen Glass of Grand Valley State University in Michigan, was based in part on previous research that said people must lift no less than 60 percent of the maximum weight they can lift to increase the size of their muscles.
In a test Glass conducted involving 30 novice weightlifters, 17 men and 13 women, not a single person chose to start at the 60 percent mark.
"When it comes to strength training, people need to know what is heavy and what's not," Glass said.
Glass did a similar study a few years ago involving aerobic exercise and learned that most participants were able to find a starting point at which the exercise would be beneficial. It was because things like walking, riding bikes and climbing stairs are common, and most people can tell what the difference is between light, medium and heavy aerobic exercise.
Lifting weights is not the same thing. Most people don't do that during a normal day, so when they hit the weight room, they have no idea what to expect.
"If you lift 50 percent of what you can, that may feel moderately difficult," Glass said. "But people don't realize it's not near the weight you need to lift to induce gains."
In the study, Glass asked the participants to simply choose a good starting point and work out however they wanted. A little after the starting point had been chosen, the participants were asked to lift as much weight as they possibly could to determine their maximum.
Novice weightlifters need to max out
By crunching those numbers, Glass found that nobody picked the 60 percent number that has been cited as the point at which lifting weights starts to work.
Likewise, most novice weightlifters didn't understand that maxing out, slowly increasing the weight until they're lifting the most they possibly can, is the way to get the most benefit from the workout.
"The intent is to lift to fatigue," he said. "Fatigue means you pick up heavy weight and you lift it until you can't lift it anymore. That's not the perception most people have in their day-to-day activities."
The result, the study concluded, is that it "appears that individuals are unable to select an appropriate weight that will provide them with any benefits of weight training, and as a result, may be more likely to become discouraged and quit."
Some skeptics of Glass' research might say that novices lifting too heavy are naturally more prone to injury. Glass said studies showed most injuries among beginners come when they try to max out early during a workout.
One of the recommendations learned from the study, published in the Journal of Strength and Conditioning Research, is that beginners should ask trainers to help them figure out what they should be lifting.
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