Education is Important, but Big Biceps are Importanter – The Science Behind the Peak

We all learn back in school that genetics influence a wide variety of our traits from eye color to height to hair color to basically every single aspect of our outward appearance. But what we often don’t think about is how it affects our appearance in bodybuilding – especially when we’re in the gym for years and years trying to shape and grow and change that genetically predisposed appearance. That is why today I present you with: Education if Important, but Big Biceps are Importanter – The Science Behind the Peak.

Short v Long 2

Want to know more about how genetics affect your weight training?

Check Out: The Genetic Lottery

Because of genetics, some people make superior gains in size while others barely make any, even when following the same strength and training program. Think about it, if all you had to do was follow the strength program of Arnold Schwarzenegger, there’d be millions of individuals walking around looking like Mr. Olympia. (and obviously, you don’t see a bunch of Terminators sitting at your local Starbucks or grocery shopping at Stop & Shop on an average day.)

So why do I bring up all this science-y genetic stuff? (Other than I really like knowing the science-y stuff behind our bodies.) Because it could very well be the reason why you have been pounding away in the gym for years only to be walking around with less than stellar bicep peaks (like yours truly).

Bicep Muscle

You see, genetics play a role in the size and shape of your muscle bellies. I know what you’re thinking.  Muscle bellies?? My muscles have bellies now?? A muscle belly is the sum of all the muscle fibers in any given muscle. These muscle fibers are grouped into bundles of around 150 fibers called fasciculi.  Each one of these individual fibers can be broken down into hundreds or thousands of myofibrils. The myofibrils are surrounded by sarcoplasm and together they constitute the contractile part of the muscle. In other words, muscle bellies are the part of the muscle between the tendons. Muscle bellies also refer to the length of this part on a certain individual.

Muscle Belly

So, if my muscle bellies are genetically determined? How many different types of muscle bellies are there?! – Short, Long, aaannddddd somewhere kinda in between.

A short muscle belly is one where the muscle attaches high on the tendon, this means that the tendons are somewhat long and the muscle is somewhat short. When your biceps muscle attaches high on the tendon, that means it attaches far from the elbow. This tends to create a gap between your biceps muscle and your forearm. Short biceps (or any other muscles) peak and protrude more easily.

Short v Long

A long muscle belly is when your muscle attaches very low on the tendon OR very close to the attached bone. When talking about your biceps, the shorter the gap in between your bicep and your forearm, the fuller and rounder it appears. What does this mean for your peaks? Welllllll, we’ll just say they’re more like sloping hills.

Unfortunately there is not a whole lot you can do about the size and shape of your muscle bellies. No matter what you do your tendon and muscle length will remain the same. Having long or short muscles doesn’t affect much other than the way your muscles look when flexed. Learn to love your muscles and choose workouts to maximize yours specifically. (And if you want to try and at least grow them a bit – Check out some of my favorite exercises here: Girls Just Want to Have Guns – P.S. Don’t be afraid of the title – they work for guys too!)




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