Effects of Variety on Training the Posterior Chain
Here are two questions I am often asked about my training facility:
“Why do you have so many pieces of equipment for the muscles of the posterior chain?” and
“Why do you have two back extension machines, one that is flat and one that is inclined at 45 degrees?”
The answer to both these questions is the same, which is that it’s important to have a variety of exercise equipment to vary motor unit recruitment patterns.
Take the example of the two back extension benches. Each of these benches allows for the performance of exercises that work the following posterior chain muscles: glutes, hamstrings and erector spinae. These sets of muscles are considered part of the posterior chain because of the anatomical structure of the sacro-spinal and sacro-tuberal ligaments. Stay with me.
The point of overload for these muscles is influenced by the particular orientation of the body in relation to the floor. Although the 45-degree incline bench does not allow for the same level of stretch for the erector spinae muscles as the flat version, the incline bench does permit a greater percentage of recruitment of the hamstrings compared to the flat version. It’s not that one exercise is superior to the other but that each offers a different training effect.
For long-term results, I’ve found that varying the points of overload every four to six workouts will help ensure better balanced strength, faster increases in strength and hypertrophy, and greater protection from injuries.
Furthermore, you can increase the number of permutations of the back extension exercise by varying the position of the load, such as holding a dumbbell on the chest versus holding a barbell at arm’s length with a wide grip.
Copyright ©2010 Charles Poliquin