You cannot confuse a muscle.
For something to be confused, it must first be able to understand at some level. Of course, as our muscle fibers are just muscle fibers, they do not have the capacity and will never have the capacity to understand at any level. Because they have no thought process, they don’t know if you are lifting a weight or lifting a mountain, they don’t know if you have run for 1 mile or 100. All your muscles do is react to the stimulus you have given them.
Muscles can contract in three ways:
- Concentric contraction = contraction while shortening
- Isometric contraction = contraction without changing length (clenching)
- Eccentric contraction = contraction while lengthening (braking)
Types of Muscle
There are two types of muscle: striated and smooth. Striated muscles have stripes or striations under a microscope. These striations are due to the arrangement of muscle fibers which run in parallel lines. All of our skeletal muscle such as biceps or quadriceps are striated muscle, another type of striated muscle are those within our heart that make it pump. Smooth muscles are a lot more gradual and we cannot control these muscles such as our muscles throughout the digestive system.
Calcium Stimulates Contraction
The striated muscle receives its signals from the brain via motor neurons. Noth mechanisms lead to a change in calcium levels in the muscle cells. Causing the activation of myosin and muscle contraction.
Smooth muscle cells can be activated by neuronal signally or hormones. Both mechanisms change calcium levels within the muscle cells which also activate myosin and muscle contraction.
Some smooth muscles are in a constant state of contraction, an example of this is the tiny muscle that lines our blood vessels. When they relax in your face, you blush.
Recovery & Repair
When we exercise satellite cells (stem cells) repair the damage which then causes hypertrophy or hyperplasia. Full details of this can be found on our Hypertrophy vs Hyperplasia article here.
In summary, a muscle cannot be confused and instead you should focus on performance, load and volume.