MUSCLE BOOSTER #4: PARTIAL REPS
A limited range of motion can actually be good for building more muscle – as long as you do it right.
Almost every trainer you talk to will stress the importance of always using full range of motion (ROM), on exercises when you train. By and large, I agree with this advice, but “always” is a strong word. There’s a time and a place for restricting your ROM – one of those times is when purposely employing partial reps to extend a set past failure and increase intensity.
There’s a fine line, however, between shortening your ROM for a more effective workout and doing it out of laziness. Here’s how to make sure you’re doing the former, not the latter…
Partial Reps
What it is: A technique where reps are performed short of full range of motion – typically at the end of a set when strict reps are no longer physically possible due to fatigue, which doesn’t allow you to lift the weight past your “sticking point.”
Why to do it: Because you’d rather not stop to rest, lighten the weight or end the set just yet. Achieving full ROM is nearly always recommended, but partials, used occasionally, can help you extend a set seamlessly to fatigue your muscle fibers that much more, even if it’s just in the bottom or top half of the movement.
How to do it: When using partial reps, a majority of the set is still taken through a full ROM. Using biceps curls as an example, let’s say you choose a weight you can do for 10 strict reps. After your 10th rep, when you’ve reached failure and are unable to move the bar past a certain point – somewhere around halfway up, a common curling sticking point – simply do reps where you’re lifting the weight as far up as possible, even it’s only a few inches as you become more and more fatigued.
These reps are typically done quickly, not slow and controlled, and you likely won’t be able to do more than a handful of partials before the burn in your muscles is unbearable and the weight isn’t even budging a few inches.
Key point here: Even though your ROM is limited, stick with proper form in all other areas. For example, with curls, keep your elbows pinned to your sides and don’t lean back, even when doing partials.
Aside from curls, partial reps are also great to use on leg day. Here’s a sample workout:
Sample Partial Reps Legs Routine
| Exercise | Sets* | Reps | Rest |
| Squat | 4 | 8-10 | 2 min. |
| Leg Press | 3 | 10-12* | 2min. |
| Leg Extension | 4 | 12-15* | 1-2 min. |
| Leg Curl | 3 | 12-15* | 1-2 min. |
| *Perform partial reps at the end of your last 1-2 sets after reaching failure on full ROM reps. Do partials until you can no longer budge the weight. When doing partials on leg press, either have a spotter close by or engage the safety bars so that the weight doesn’t fall on you. | |||
Close-Grip Bench Press**
- Sets: 4
- Reps: 8-10
- Reps: 2 min.
Dumbbell Lying Triceps Extension
- Sets: 3
- Reps: 10-12*
- Reps: 2 min.
Seated Overhead Dumbbell Extension
- Sets: 3
- Reps:12-15*
- Reps: 1-2 min.
Reverse-Grip Cable Pressdown
- Sets: 3
- Reps: 12-15*
- Reps: 1-2 min.
*Perform partial reps at the end of your last 1-2 sets after reaching failure on full ROM reps. Do partials until you can no longer budge the weight. When doing partials on leg press, either have a spotter close by or engage the safety bars so that the weight doesn’t fall on you.