The Key to Muscle Growth
A couple of weeks ago, we talked about gains. But not the beach body ones, rather the ones that happen via the nervous system. Check back to The Movement – 116 for a refresher on the nervous system adaptations to lifting, but many of you may just want to know: How do I make my muscles grow?
That’s what we’ll touch on this week in The Movement.
The Key to Muscle Growth
Most weightlifters, and even newbies, are familiar with the most fundamental law of exercise known as overload. Related to hypertrophy, it means if you want your muscles to grow, you have to work them at tensions close to their max.
The explanation for a five-year-old is that these workloads cause damage to the working muscle fibers, and the body then repairs the intentional injury and conveniently makes it even stronger to withstand more force.
But there’s a whole lot more behind that explanation, as you can see from this diagram:
That is a schematic showing the activation of muscle satellite cells. If you want to dive in, click here and have fun, but it will not be tested nor change your life unless you’re doing muscle research. The main thing I want to point out is the tiny cells responsible for muscle growth called satellite cells.
When they receive the message, the muscle satellite cells replicate and generate new muscle fibers. Thus the key to muscle growth is stimulating the satellite cells to go to work.
The satellite cells respond to many things, including nutrition and hormones, but the most potent producer of muscle growth is resistance training, and there are two primary ways it works:
- Mechanical Loading
- Metabolic Stress
Mechanical Loading
Mechanical load doesn’t necessarily mean muscle contraction. Studies show that loading muscles without contraction (like stretching) can also yield muscle growth, but you’ll get greater mechanical loads when the muscles get flexed.
You can do this by lifting heavy weights more slowly or by lifting light weights to failure, but explosive training (plyometrics or ballistic weightlifting) doesn’t work too well. Even if it’s a heavier weight moved quickly—which requires a high degree of muscle activation— it’s too quick for a high degree of mechanical loading.
So if you want muscles gains, slow it down and feel the pump.
Metabolic Stress
Another thing that’s shown to promote muscle growth is the build-up of metabolic byproducts, like hydrogen ions and lactate, within the muscle. This topic could get deep, and we’ll avoid it for now; just know that the burn you feel when working really hard is producing messengers that kick the satellite cells into gear.
It’s also a mechanism behind blood flow restriction, which has been hot within rehab and the exercise science circles for a bit, but it looks like it just hit the mainstream.
Bigger and Stronger…kind of
Many believe that if a person wants to get stronger, they have to build more muscle to make it happen.
More muscle does help produce more force, but as Chris Beardsley explains so well, strength is highly specific, and how you demonstrate strength matters immensely. So, for example, compare the demands of a powerlifter and an Olympic lifter. They both need strength, but it looks different.
Additionally, there are other means for muscle growth, such as expanding fluid within the muscle and adding connective tissue, that we didn’t touch on here. So in some ways, you may increase muscle size and not get stronger.
Check out Chris Beardsley for more information, presented relatively simply, on strength and hypertrophy. He’s got a ton of information on his social and website, but you don’t need to dig, just grab his e-book: Strength is Specific (for only $3 bucks.)
Now as CT Fletcher says, “I command you to grow!”
