Anabolic Bodybuilding Supplements

FREE Muscle Mass Program
Increase Your Muscle Mass Faster
Than You Ever Thought Possible!

Enter your first name and a valid email address
for free instant access to the muscle mass workouts.

First Name:
Email Address:

Genetics and Bodybuilding

Article care of

The Genetics Factor of Muscle Growth and Strength

Slow and Fast Twitch Muscle Fibers

Understanding the way your muscles work and why is not necessary to get bigger or stronger. However, to reach a competitive status or to develop your body to the point where people other than yourself notice that you work out, it is imperative.

Muscles are made up of two types of fiber, slow twitch and fast twitch. Determining the ratio of slow twitch to fast twitch muscle fiber in a given muscle group is a key factor in determining what type of training program is best suited for you. Slow twitch muscle fiber is capable of handling prolonged activity but can generate only a relatively low force of muscle contraction while fast twitch muscle fiber has a relatively low endurance but creates a more forceful contraction. Every one has a predetermined ratio of both types thus determining the higher ratio of fast to slow twitch will allow an individual to train accordingly; enabling them to focus on developing the muscle fiber type they have more of in each muscle group.

To determine the ratio of fast and slow twitch fiber in one of your muscle groups you will need to experiment with different weights to see if the muscle has more of a tendency to be explosive for short periods of time or if the muscle has less of a tendency to perform explosively and more of a tendency to handle moderate weight for a longer duration. Some examples of athletes with a higher percentage of fast twitch muscle fiber would be a competitive sprinter, distance jumper or power lifter. Some examples of athletes with a higher percentage of slow twitch muscle fibers would be a competitive wrestler, a rower or a distance runner.

After you have determined a muscles specific ability the muscle should be trained accordingly; for instance the Triceps usually contain predominantly fast-twitch muscle fiber while the Soleus (calf) contain predominantly slow twitch muscle fiber. Therefore the triceps should be trained with more explosive concentric (positive) and controlled eccentric (negative) movements with muscle failure resulting in the rep range of 5-8 reps depending on the lifters ability to isolate and squeeze the muscle. The Soleus should be trained with slow deliberate rhythmic repetitions with muscle failure resulting in the 10-16-rep range. If you are one of the “low reps to get big” people look at it this way; on average the Soleus contains 10-25% fast twitch muscle fiber, now if we train our Soleus according to a fast twitch muscle regimen we will be stimulating 10-25 percent of our Soleus neglecting the vast majority of the muscle fiber (75-90%) which is slow-twitch muscle fiber, however if we train the Soleus as an endurance muscle we are stimulating the vast majority of the muscle fiber as it is made up of “endurance fiber” thus stimulating muscle growth and strength to a much greater extent.

In conclusion training a muscle in compliance with its natural ability whether it’s explosive or high endurance will further develop the muscle to reach its full potential. Training a muscle in a manor that neglects more muscle fiber than it recruits will obviously yield minimal results. The ratios of the muscle fiber in the human body cannot be changed only developed. This is one of the reasons variety in training is crucial; all muscles have both slow and fast twitch muscle fiber and all of these fibers can be developed making it advantageous to determine what the majority of the fiber consists of and training the muscle accordingly.

Anabolic Bodybuilding Supplements

Sign up to receive the FREE Anabolic Bodybuilding Newsletter!
We cover the hottest topics and update you with the latest information.
Our features include the following:
  • Hardcore Muscle Building and Fat Loss Tips
  • Nutrition and Diets
  • Product Reviews
Click Here To Sign Up Free


[Contact Us]
[Home] [Store] [Andro Shock] [Pumped Extreme] [Fat Melter]
[Articles] [Tips] [Exercise Guide] [Terms] [Reviews] [Links]

Copyright Muscle Mass Magazine 1996-2017