In life, it's rare that partial work will ever get the whole job done, but when it comes to this lifting technique, that's just what it does.
A partial rep is when you perform just a portion of a repetition. Whether it's squats that only go down a few inches, the top half of a bench press, or the bottom part of a curl, these partial rep movements have been proven to generate impressive results.
This lifting technique helps to increase your maximum strength, and to overload all the fibers in your muscles. The University of Southern Mississippi researchers found that doing partial reps did no harm, and in most cases produced the same effects as full range of motion exercises.
Here are the two different forms of partial reps:
Partial Reps at the Weakest Point
An example of this is the bottom of the bench press or the bottom of a squat. You would only lift the weight halfway up and then back down for each rep.
Some benefits of working within the weakest range of motion are that you will be using relatively light weight, therefore minimizing your risk of injury. Don’t be deceived by the light weight. Remember, you are completing all partial reps in the weakest range of motion.
This is where the muscles contract the hardest as they struggle to complete each rep. The weight may be light but the training is intense. Partials at the weakest point also allow for higher volume work.
Partial Reps at the Strongest Point
You may have heard of this as “power factor” training. The theory behind this is that you work in the top half of the movement – the strongest point. This will allow you to lift maximum weight. Because there is no weak point, you will be lifting heavier weight than usual. However, there is a greater risk of injury when going heavy, so use common sense, warm up properly and get a spotter to reduce the chance of injury.
It's best to do partial reps at the strongest point at the very end of a normal set when you can no longer complete a full rep. Use this technique for only the last set of an exercise.
Lower the weight two to five inches from the top position and return to the start. Choose one exercise and do two or three sets this way. Follow with one full range of movement set of that exercise. Then finish that body part workout with two more exercises using full range of movement reps for all sets.