Lifting lighter weights can make muscles bigger

Yo!  You want to grow big muscles? You have to lift heavy.. there is no other way!

So goes the myth.  True, lifting heavy weights is great for increasing muscle mass, but it's a myth that this is the only way.

Nick Burd and his peers from the Exercise Metabolism Research Group at McMaster University, Ontario, recently published a study that looks beneath the skin and beyond boisterous gym talk claims to see exactly what happens to muscles when a person lifts weights, more specifically, how people respond to lifting heavy weights and light weights.. Which protocol makes your muscles bigger?

Both.

The really interesting part is how proteins in muscles respond after training is done.

Always keep in mind that exercise is a cellular stimulus.  No matter what is going on on the outside, no matter what sport or activity, you are imparting a stimulus to cells in your body.  If there isn't enough stimulus cell response will be small or nothing.  Doing more only goes so far as well.. there is a biological limit to the amount of stimulus you can respond to.  Sure.. you can continue to exercise beyond this point, but no further fitness gains will be made and risk of injury and excess fatigue increases.

So what about stimulating muscles to get bigger?

Lifting heavy weights to failure, where your last repetition cannot be completed, is a proven method of increasing strength and muscle size.  Typically somewhere between 60% and 90% of a persons 1RM is lifted until failure, with 70% to 80% of 1RM being the most popular.

1RM is the heaviest weight you can lift 1 time.

There's some trouble using 1RM to set training values.  To find 1 RM you have to lift the heaviest weight you can possibly lift.  No problem for well trained people, could mean injury for those just starting out or with modest experience, and for the uninitiated, really hard lifting can be intimidating or simply seem like too much effort.

Turns out that finding the weight that causes you to reach failure between 8 and 12 repetitions gets you into that 70% to 80% of 1RM range.. so no need to test 1RM, just do trial and error to find the weight you can't lift more than 8 to 12 times.

What about a weight that is much lighter.. light enough that you don't reach failure until around 30 repetitions?

That's for wimps! Or is it?  Failure at 30 reps feels about the same as failure at 8 reps so you still have to be focussed and motivated to push yourself.  And Nick Burds study clearly shows that protein synthesis, the actual biological process of building muscle, is greater the day after lifting 30% of 1RM to failure than lifting 90% of 1RM to failure.  24 hours after the workout the high rep/ low weight groups muscles were still responding, but the low rep group?.. Not so much..

In this study 90% of 1RM resulted in about 5 reps to failure, where 30% of 1RM gave 24 reps to failure.

In a follow up study to be published soon,  Burd et al will show how those completing an actual training program either following around 30% of 1RM or 80% of 1RM to failure both gained the same amount of muscle.  Stay tuned for more details on that study..

Interestingly when about the same amount of work done in the 90% 1RM to failure group was work matched to the load in the 30% 1RM to failure group, very little (comparatively) protein synthesis occurred.

Hu?

Lifting 10 pounds 10 times equals a volume load of 100 pounds- 10 reps X 10 lbs.

Lifting 5 pounds 20 times also equals a volume load of 100 pounds, the same total amount of work done by the muscles doing the lifting.. but does the same amount of total work with a lighter weight cause the same muscle adaptation?

No.

But wait a minute.. isn't this study about proving how lifting lighter weights lots of times can equal lifting heavier weights fewer times?

Yes, and it does.

The difference is going to failure.

If the workload is divided up in such a way that it can be easily completed, that is, without experiencing the struggle associated with lifting until you can't lift anymore, then the muscles don't receive the stimulus that is best for provoking them to get bigger.

STRENGTH

If you need more strength then lifting lighter weights lots of times will still work.  So you can get bigger and stronger muscles with lighter weights.  But if you wan't to maximize the strength needed to lift heavy loads, you won't be able to do that without lifting heavy.

Great now I'm more confused than ever!  How the heck does this info help me?

First, never look for one special routine to be THE workout that does everything in less time with less effort.  That concept is a great marketing gimmick, but is.. a bunch of BS.

Here's the summary:

To gain muscle mass, whatever weight you lift, you have to repeat lifting it until you can't lift it anymore. Do 2 to 4 sets of this with a few minutes rest between.  Consume a protein source immediately after your workout.  500ml of skim milk works great.  So does 1% chocolate milk.  A chicken sandwich works too.  Ditto for rice and beans.  The milk source might be one of the better choices, but not everyone drinks milk.

The repetition range that studies show work well for gaining muscle mass is anywhere between 5 and 30 repetitions, so long as when you get there, you can't complete another repetition.

It's possible that even more reps will still work, so long as you go to failure.  More studies needed to confirm what is best, and best for what purpose (are you a linebacker or marathon runner?).

Heavy weights have a better chance of causing injury, but lifting heavy weights is needed for gaining maximum strength, so proper preparation is the caveat for heavy lifting.  This study does not suggest those needing or wanting maximum strength can swap out heavy weights for light weights.

Lifting lighter weights is a better option for beginners and for seniors trying to gain or sustain muscle strength and size.

Do you really have to go to failure every time? Is that what this means?

No. That's absolutism.

One would lift weights to failure only once they have completed a physical preparation period of easier exercises to build exercise tolerance, learn technique, and take care of existing posture and strength imbalances.

During any one workout, you should only push your limits when you are recovered enough to do so.  Pushing limits when fatigued increases injury risk and more often than not just makes you more fatigued instead of more fit, bigger, faster, or whatever you're tying to train.

Had a great hour long conversation with the study lead author (Nick Burd).  He had a great tip related to building lean muscle:  Studies show that taking NSAIDs like Advil/ Ibuprofen after weight training interferes with the biochemical process of building lean muscle; so you train, but your muscles ability to adapt to that training is impaired by the drug.

So if you're thinking NSAID's will help reduce muscle soreness you may have, that may be true, but it is also true that doing so will prevent your muscles from getting bigger- from that workout anyway.

The biggest take home from this?

What you know can help you.  We may be fairly far removed from the world of a researcher, but what the researcher discovers can help us in our day to day living, and in this case, maximizing our ability to gain muscle mass.