IGF-1 is a potent anabolic hormone that has direct effects on the increase in muscle protein synthesis and act as a muscle growth enhancer. There is a direct effect on muscles. During exercise, muscles not only produce more IGF-1 than the liver, but also use more circulating IGF-1; IGF-1, remain elevated in muscle tissue for some time after that, with anabolic effects up to 72 hours post-workout, then the idea is to know the best way to increase IGF-1 with the training.
One of the most effective ways to increase IGF-1 is using eccentric exercises; in the early 90s, there was a book called “Bigger muscles in 42 days’ written by Dr. Elliot Darden. The book had a revolutionary approach to strength training, as quoted in their assumptions, as people need to spend less time in the gym, emphasizing eccentric contractions.
If you look at most people pay little attention to the eccentric or lowering; in this case, lower the weight by controlling gravity could give some surprises. During the positive work (concentric contractions), the muscle fibers shorten, while working during the negative (eccentric contractions), the same fibers lengthen. Although the rise and fall may seem a very simple process, physiological adaptation to muscular differences are very different.
It emphasizing the eccentric contraction it is associated with positive changes in promoting strength and lean muscle mass; eccentric contractions are so important that if the eccentric contraction for a given year is removed, the strength gains are reduced. In the studies we know, programs concentric strength training with concentric and eccentric programs, concluding all the eccentric overload increases by 40-45% strength after a few weeks, because primarily active compared, muscle fibers fast twitch, which are more likely to lead to increased muscle pain and muscle growth.
Although IGF-1 and testosterone is influenced by diet, exercise and lifestyle, increased muscle anabolism is associated with an increase in intramuscular hormonal expression; then you need to know about the best way to increase IGF-1 with the training.
When the eccentric phase with extra weight increases, may recruit more motor units, it causes an increased release of IGF-1, and even increase the strength in the concentric phase.
In a two stroke technique, which involves combining two exercises in a replay, a portion is concentric phase and eccentric phase movement.
To maximize the work of eccentric overload, the goal is to reach about 150% of what can normally handle in the concentric phase; if you do not use more weight, you are losing the potential of eccentric overload.
Furthermore, the method does not require pair 2/1, and can be applied to a variety of muscles; only you have to use both arms or legs in the concentric phase and turn it into a unilateral variation, independent of the type of combinations that can be generated or invent eccentric phase. It should be noted that this technique is best done with machines; otherwise the bar may fall or cause an accident on any part of the body.
Some exercises simply do not lend themselves well to the technique 2/1, being the time comes to light the technique of “two movements” that may be the best way to increase IGF-1 with the training. Here are two exercises are combined into a single repetition, making easier the concentric phase of the lift and the most difficult for the eccentric phase variation.