Why Do Muscle Champions Have Slow Eccentric Contractions Not Slowing Down? What You Must Know to Gain Muscle
Those who have experienced heavy lifting undoubtedly know the saying, 'Slowing down the eccentric contraction is beneficial for stimulating muscle growth!' The general perception is that slowing down the eccentric contraction results in a greater stretching effect on muscles compared to the concentric contraction, leading to more significant effects.'
However, the effects of slowing down the eccentric contraction period are often overestimated. In reality, many bodybuilding champions do not deliberately slow down their movements, but instead quickly complete the movements.
So, why is this the case? This article will explain some common misconceptions about why eccentric contractions are not often considered the most effective training pattern to stimulate muscle growth.
Is it true that slowing down the eccentric contraction is beneficial for stimulating muscle growth?
Muscle Adaptation
Most studies exploring the relationship between muscle growth and eccentric contraction speed are targeted at individuals who are into fitness, and in these groups of extensive training, eccentric contraction training will indeed be more effective than simple concentric contraction training. This is because modern people's sedentary lifestyles have led to a rare use of eccentric contractions, so when eccentric contraction training is performed, it can easily reveal the growth of muscle fibers.
However, these studies consistently point out that once the body adapts to this training pattern, it becomes increasingly difficult to stimulate muscle fiber growth, and corresponding synthetic effects are triggered. Therefore, slow eccentric training can indeed provide obvious results for beginners, but as muscles adapt, the results gradually diminish. It's not just about slowing down the eccentric speed.
Eccentric Contraction Results in Diminishing Returns After Adaptation
When we engage in strength training, it is primarily in the direction of both eccentric and concentric contractions. However, the bottlenecks encountered during training are mainly due to the fact that: during the eccentric contraction period, using the same resistance intensity as the concentric contraction, the resistance reduction will be easier to resist than lifting it up; this will make the eccentric contraction movement too easy, and cannot truly train our muscles.
Simply put, whether it's concentric or eccentric, as long as the resistance is the same, the muscle will use the eccentric contraction period as rest. In a 2009 deep squat training action study report, when the deep squat action is eccentric, the activation of the quadriceps femoris is only about 40% of the activation in the concentric contraction period. Furthermore, it cannot store enough autonomous muscle strength to stimulate the best effect of the concentric contraction. From the above description, it can be understood that the same resistance training during the eccentric and concentric contraction periods will double the loss of muscle growth potential.
When the deep squat action is eccentric, the activation of the quadriceps femoris is only about 40% of the activation in the concentric contraction period.
Fast Eccentric Training
According to a study on biceps training, two groups of people used different speeds to perform eccentric contractions to train. The fast group reduced the load in 0.5 seconds, while the slow group reduced the load in 2 seconds. After 10 weeks of training, the results were as follows:
1. The slow group increased muscle strength by 10% and muscle fiber volume by 8%
2. The fast group increased muscle strength by 20% and muscle fiber volume by 13%
In this study, it was found that the fast group would have more significant muscle fatigue, muscle soreness, and a 5 times higher degree of muscle tissue damage. Relatively, it also requires more time for recovery. In contrast, the slow group did not have this effect. Fast eccentric contraction training can increase the growth potential of muscle by increasing the density of fast contraction fibers; conversely, the slow group did not have this effect.
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