Is moving through a whole range of motion when you lift weights always better or are partial reps useful for building muscle?
Taking an exercise through its full range of motion means going through the full movement potential for an exercise. Conversely, a partial rep happens when you purposefully cut the movement short in some way.
But which one is better for building muscle? Jeff Nippard, a YouTuber and pro natural bodybuilder, explains both sides of the argument in the video below.
Are Partial Reps Useful or Not for Building Muscle?
The case for partial reps
- Partial reps allow you to move more weight: “while it is true that you will be able to load more weight when you cut the motion short, that actually doesn’t mean you’re putting more tension on the muscle,” says Nippard. This is because you increase the weight but decrease the distance that the weight is moving. Distance is an important metric when calculating workload.
- “Trading range of motion for weight is almost always a bad trade, but there may be a few legitimate exceptions,” Nippard concludes.
- Partial reps allow for constant tension on the muscle: by stating in the “active midrange” of a movement you can place constant tension on your muscles. Athletes who follow this idea don’t simply cut the range of motion but stop just shy of full lockout by cutting out the top and bottom of each rep.
- This way, your muscles don’t get “mini-rests”, which isn’t efficient for growth, and maintain tension throughout.
- Partial reps are only effective on free-weight isolation exercises such as skull crushers or the dumbbell pullover, as cables and machines automatically provide constant tension for the most part.
- IFBB Pros use partials: many modern day IFBB pro bodybuilders seem to favour partial reps, but there aren’t any scientific studies to back their anecdotal evidence.
The case for full range of motion
It is generally agreed that going through a full range of motion is better for muscle growth.
The best rule of thumb is to use a full range of motion most of the time by getting a reasonably good stretch at the bottom and a reasonably full contraction at the top. But there’s no need to take it to the extreme and you shouldn’t push the range of motion of exercises to the point of discomfort.
As long as you’re getting to the hardest part of a lift, you’re probably maximising the hypertrophic effects.
“A full range of motion is usually better for muscle growth, especially for the legs,” says Nippard.
Read more: How To Perform Reps for More Muscle Growth
When is full range of motion a bad idea?
Dr Mike Israetel, cofounder of Renaissance Periodization and Sport Physiology PhD, explains the exceptions to when partial reps are better than performing a full range of motion.
- athlete back barbell overhead: Photo courtesy of CrossFit Inc.