Negative Reps Training
We all know that there are two phases to any mechanical load lifted. The concentric phase producing a greater metabolic stress on the targeted muscle and eccentric training which sports scientists have now discovered releases a new found substance that immediately makes a difference to protein synthesis, the substance is called phosphatidic acid.
When training eccentrically (negatives) you also activate satellite cells that are located outside of your muscles. They respond to the damage within their vicinity by transforming these satellite cells into what science calls immature muscle fibers. This dramatically helps to repair the damaged muscle and helps it fuse, ensuring increased strength and size.
It is interesting to note that bodybuilders who reach the dreaded training plateau where they cannot lift a heavier weight is because they cannot activate satellite cells outside the muscle. This activation of the satellite cells is responsible for size and strength because you now have more nuclei available enabling protein synthesis.
The science of muscle growth explains to us that when the contractile proteins of actin and myosin bind to each other they form a "cross-bridge." The problem is that the more cross-bridges you utilize when lowering a weight eccentrically, the less tension each cross-bridge has to bear the less muscle damage will occur.
The problem with doing an eccentric lengthening of the muscles for 5 or even 10 seconds is that it will give your muscles more time to create new cross-bridges. This means less damage, less protein synthesis and ultimately less muscle growth. New research on eccentric training suggests only doing negatives for 1 to 3 seconds.
We are all about 60% stronger on an eccentric lift which means that if you are doing eccentrics for 1 or 3 seconds with the same weight that you lift concentrically then you will not get the same results as suggested. This means that you need to increase the weight when doing eccentrics.
Depending on the movement you are doing it can be done quite effectively. For example, doing leg curls where you lift the weight concentrically and then lower the same weight only using one leg. If you have a training partner he/she could press down on the eccentric to increase the weight.
It is important to note that when doing eccentrics as suggested above that you limit the amount of times you do this type of eccentric training to only once a week. Periodization is vitally important when it comes to eccentric training using negatives, so never do it every time you train.