Joe Weider’s principle of partial reps has influenced exercise science to this day. Partial rep training is a high intensity technique in which the range of motion of a certain exercise is decreased to gain an advantage.
One advantage is being able to lift heavier than normal weights by shortening the range of motion (ROM) to 3 or 4 inches near the top end or lockout portion of the exercise.
It is the lockout portion of an exercise that allows a mechanical advantage of lifting supra-maximal weights. For example, if you can bench press 250 lbs full range you might be able to handle 350 lbs or more at lockout. Using heavier weights than you can handle will stress your muscles to the maximum stimulating new growth.
Partial reps of the same fashion can also be done at the end of a regular full ROM set as burns squeezing out every last inch of movement out of the muscles.
Another advantage of partial rep training is to work around injuries such as the Spoto Press in which the barbell is paused a few inches above the chest rather than resting on the chest to reduce shoulder stress. Eric Spoto designed this exercises specifically to help rehabilitate his shoulder after surgery.
I also have suffered two minor shoulder injuries in which the inflammation prevented a full ROM in virtually every overhead press exercise. However, I was able to continue training using the seated and standing half press.
Although not ideal, research has shown that training a muscle through a short ROM increases the strength of the muscle through the full ROM almost to the same extent. As a result, I was assured that not only could I maintain the size and strength I had during injury but I could actually make improvements as my shoulder injury continued to heal.
Partial rep training can also be used to work on a sticking point within an exercise. If a sticking point exists within a given exercise it is sometimes more effective to focus on building strength in this area as opposed to continuing to push yourself through the entire ROM.
For example, on the bench press a sticking point exists at about the halfway point. Set up a power rack with the pins just a few inches below this height and explosive break the bar from the rack several inches but fail each time to lockout at the top. The amount of energy you have is finite. Training in this way focuses all of your energy where it needs to go – the sticking point.
There are many other ways partial reps can be employed in your training. I use them in almost every workout and believe they are a natty’s salvation. If you haven’t used partial reps in your training you are missing out on some results. Give them a try for a week or two and a guarantee you will soon realize the benefits.