Eccentric training or negative training is a great way to increase strength
The catch is, all forms of weight training favor an increase in size and
strength if performed properly in addition to proper rest and diet.
As with all different styles of training, your lifting must be consistent
with your goals.
Since your body can handle a heavier load during the eccentric phase of an
exercise, eccentric training is the best way to increase strength. Will it
increase just eccentric strength or overall strength?
This depends on the way you train eccentrically.
If you use heavier weights than you can handle concentrically (positive part
of the motion, lifting against gravity) you will definitely cause your body to
If your eccentric training consists of using weights of moderate intensity
(less than 80% 1RM) you will most likely not increase strength.
If this is the style of lifting you do, it could be the best way to increase
muscle mass. Remember, to increase muscle mass along with a hyper-caloric
diet, you need high training volume.
The lifting phase is insignificant to the time under tension. With
regards to training volume and hypertrophy of muscle, a 1 minute set is a 1
minute set. You can read about it on the weight training volume
The bottom line is, if eccentric strength is what your goals is, focus on it.
If overall muscle development is your primary goal, focus on a balanced program
using a variety of training modalities and have a diet, rest, and supplement
regimen consistent with your goals.
It should be noted that heavy eccentric training has been associated with
increased potential for injury. It is recommended that negatives only be
performed once a week at the most.