Building muscle doesn't require lifting heavy weights: study

Current gym dogma holds that to build muscle size you need to lift heavy weights. However, a new study conducted at McMaster University has shown that a similar degree of muscle building can be achieved by using lighter weights. The secret is to pump iron until you reach muscle fatigue.

"Rather than grunting and straining to lift heavy weights, you can grab something much lighter but you have to lift it until you can't lift it anymore," says Stuart Phillips, associate professor of at McMaster University. "We're convinced that growing muscle means stimulating your muscle to make new muscle proteins, a process in the body that over time accumulates into bigger muscles."

Phillips praised lead author and senior Ph.D. student Nicholas Burd for masterminding the project that showed it's really not the weight that you lift but the fact that you get muscular fatigue that's the critical point in building muscle. The study used light weights that represented a percentage of what the subjects could lift. The heavier weights were set to 90% of a person's best lift and the light weights at a mere 30% of what people could lift. "It's a very light weight," says Phillips noting that the 90-80% range is usually something people can lift from 5-10 times before fatigue sets in. At 30%, Burd reported that subjects could lift that weight at least 24 times before they felt fatigue.

"We're excited to see where this new paradigm will lead," says Phillips, adding that these new data have practical significance for gym enthusiasts but more importantly for people with compromised skeletal mass, such as the elderly, patients with cancer, or those who are recovering from trauma, surgery or even stroke.

The findings are published in PLoS ONE.

More information: … journal.pone.0012033
Citation: Building muscle doesn't require lifting heavy weights: study (2010, August 11) retrieved 24 October 2019 from
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Aug 11, 2010
Are they mutually exclusive?

Good way to bulk up is using both. Five or six reps of max weight immediately followed by five or six reps at 50% the weight works wonders.

I think a lot of people just use one weight, 10 reps 3 times automatically. Like your diet, change up exercise routines to keep it diverse.

My two cents.

Aug 11, 2010
This is new? I've heard this many times before.

Aug 11, 2010
I, too, knew of this many years ago, but I figure that because it was not published as a scientific study, but rather was the result of practical use in the gym, it is considered "new" to academia. This reminds me of the study that showed breast milk to be better for babies nutritionally than formula. I guess it wasn't "better" officially until the research was published . . .

Aug 11, 2010
Hmmm. Wikipedia says: http://en.wikiped...ertrophy

It states that weightlifters who are stronger than bodybuilders use low rep high weight training, whereas bodybuilders, who want the appearance of HUGE muscles train with high rep low weight.

For weightlifters, myofibrillar hypertrophy increases the muscular strength, whereas for bodybuilders their training increases the sarcoplasmic fluid in their muscles, increasing their stamina, but giving a relatively low increase in strength, with the appearance of very large muscles.

This suggests that high weight low rep increases strength much more effectively, whereas high rep low weight increases stamina. Obviously any exercise will do a little of both, but the trend seems to contradict this article.

Aug 11, 2010
I think they need to define strength. If you want endurance, use low-weight high-reps. If you want power, use high-weight.

Aug 11, 2010
"In conclusion, we have demonstrated that low-load high volume resistance exercise has a potent stimulatory effect on anabolic signalling molecules, MyoD and myogenin mRNA expression and muscle protein synthesis. Our results support previous findings that demonstrated after 16 weeks of isometric training at 30% maximal voluntary contraction that significant increases in fibre area can be achieved ... however, a training study in which these distinctly different exercise loads (90FAIL and 30FAIL) are utilized is clearly warranted to confirm our speculation."

So, they've proven that both are equally effective in triggering the construction of muscle proteins and even muscle fibres, but they haven't yet established that the lighter weights are equally effective in developing strength.

Aug 12, 2010
It is new information. It's true bodybuilders has a higher rep count than weightlifters, but only up to 12 reps. Normally they recommend 8-12 reps for bodybuilders, and many sets for each muscle group.

With at least 24 lifts before fatigue, that's much higher than what pro bodybuilders use.

Aug 12, 2010
This makes some good sense and glad to say I have long suspected this. Hopefully we can get some nice proof to link relaxation cycles with development of fast twitch vs slow twitch. It is a bit more obvious though when you think about it, the heart pumps with very little rest and is mostly fast twitch- while a bulky weight lifter rests muscle groups for days. Bruce Lee or Michael Jordan would be a good example (but i'm rather sure bruce was quite a bit stronger ;) while body builders who are relatively weak for their mass and sometimes overall have large rest periods sometimes consisting of days between muscle groups.

Aug 12, 2010
I'm sorry, did I miss something , how was this experiment carried out, where are the specifics??

Aug 12, 2010
I'm sorry, did I miss something , how was this experiment carried out, where are the specifics??

At the bottom, where it says "more information".

Aug 13, 2010
Peary Rader's 20 Rep squat routine has been around for decades and is probably the most effective way to build mass. The blurb under the title is inaccurate as even lifters with minimal knowledge know that training muscle size vs strength/power training are very different things. You're not going to see Olympic lifters start doing 24 rep leg extensions anytime soon.

Aug 16, 2010
If I want to know which way works best I think I will ignore this article and ask someone that has had practical experience.

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