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Secrets to Getting a Flatter Stomach Part 2
Muscle Fiber Specificity
Your core can be trained every day, so train your core every day. It takes only twenty-four hours for the muscles of your torso to fully repair. After twenty-four hours, the core is ready to be trained again. This is because it is composed predominantly of slow twitch muscle fibers. Slow twitch muscle fibers are endurance fibers. They produce very little force compared to the larger muscles of the body. But unlike the other larger muscles of the body, the muscles of the core can produce low levels of force for extended periods of time without producing significant fatigue.
Slow twitch muscle fibers are high in red blood cells. Red blood cells contain a great number of mitochondria. Mitochondria rely heavily on oxygen to produce energy. The oxidative system of the body is responsible for delivering oxygen to these working muscles. The oxidative system of the body is used in activities lasting between three minutes and up to and above two hours. This means that in order to produce specific adaption, we have to train for extended periods of time with little if any rest.
With this in mind, we must design our core training program to fully stimulate and fatigue this muscle group. We do this in two ways. First, we expose these muscles to large amounts of time under tension. Second, we perform core workouts with very little rest.
Now you can see why it is so difficult to make this part of the body develop. Most of us do not have the patience or endurance to stimulate this muscle group. To ensure that proper time under tension is achieved, timing exercise sets is essential. I use a Gymboss interval timer to do this. Each set is performed for a set amount of time. The timer counts down the seconds until the set is completed. When the set is completed, a separate timer begins to counts down the rest period. When the rest period is completed, the timer begins again.
It is difficult to perform a lot of repetitions with very little rest. This is why I perform core workouts in a circuit fashion. Exercises targeting different areas of the torso are used. While one area of the torso is being trained, the others areas are allowed to rest. Performing core workouts in a circuit fashion ensures that the heart rate remains elevated, stressing the oxidative energy system, while at the same time allowing one to recover.