Should You Do Partial Reps? Gain Strength, Size, and Power?

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Every gym has a few bros or in most cases, a few hundred bros who never lifts through a full range of motion. They do half curls, quarter squats, and partial bench presses.

One of the obvious perks of partial reps is that you can use higher loads given the same effort and volume.

Could there be any benefit in doing this? Could sacrificing range of motion produce better results? Or is it just a way to stroke your ego?

Let’s cut through all the bro-science and see definitively if partial reps are better or worse than full reps.

To do this, I’ll be digging through the research on partial rep’s effect on power, strength, and what you all care about most, muscle size.

Effects on Power

Power is an interesting factor as it can be deeply useful for athletic sports as well as lifting performance.

When comparing full reps vs partial reps for power, studies show full reps take the cake (1,2). However, keep in mind these studies are comparing exclusively full range against exclusively partial training.

You’ll see a lot of athletes incorporate both into their training, so research replicating a combination might be more applicable.

One study showed when volume is matched, combining both full range sets with sets of partial reps can be beneficial for power (5).

For power development, I would suggest lifting through a full range of motion for most sets, but including some sets of partials will also be beneficial especially in key ranges of motion.

Effects on Strength

As for strength, when you compare exclusively partials to full reps, full reps once again comes out on top (3).

When you compare full range to full range combined with partials, solely training with a full range of motion produced more strength gains in the bench press, even when testing for partial range of motion strength (4,10).

However the opposite effect is seen in this study looking at squats (5).

In general, a fuller range of motion seems to be more beneficial (6).

If you’re lacking overall strength, doing solely partials isn’t effective.

On the other hand, if you need to build strength in a very specific range of motion of your squat, adding in partials will bring up your weakness thus increasing overall strength and showing a better effect in some studies.

So the prescription for strength gains is similar to power gains.

A majority of your sets should be done with a full range of motion, but adding in partials where you’re particularly weak is wise on some exercises.

Effects on Size

Set for set, full range is also the king for muscle growth in a variety of exercises (2,3,6).

One study in particular also showed full reps cause more regional hypertrophy (muscle growth in particular areas of a muscle) as well as being superior for maintaining muscle during a detraining period (6).

So if you want maximum gains and to keep those gains if you’re ever stranded away from the gym for whatever reason, full reps are superior to half reps.

This is like anything else in life. A full cake is better than half a cake. A full car is better than half a car. A full girlfriend is better than well, you get the idea.

Anyways despite partial reps allowing you to use higher loads, they’re just generally inferior because full reps allow you to apply tension across an entire muscle length including the stretched position which research has shown us to be particularly anabolic (7).

In fact, full range of motion may only matter because it’s able to train muscles in the stretched position (most anabolic position).

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The Case For Partial Reps

There is one study that supports doing partials for hypertrophy.

This study looked exclusively at partial reps vs full reps in the lying barbell skull crusher and it showed the partial rep group to gain significantly more muscle (8). The researchers concluded hypoxia (oxygen restriction) was greater in the partial reps thus explaining the results.

While I do think hypoxia played a role, I don’t think it fully explains why partial reps did almost twice as good as full reps in this study. If hypoxia was the main contributor to enhanced hypertrophy we would see much greater hypertrophy in other partial rep studies as well as studies looking at blood flow restriction training, but we don’t.

This study is a bit of an anomaly as far as results go, but if you take a closer look, a combination of factors can explain the better muscle growth with partial reps.

  • Rep tempo was kept the same in both groups at 1 second lifting and 1 second lowering. This means even though the full range group had almost 3 times the range of motion to lift through, they had to do it in the same short time. Inevitably, they had to lift very fast using momentum and letting the weight drop without much control. This would allow for more optimal lifting tempo in the partial group.
  • The top portion was neglected for the partial group. The lying barbell skull crusher is very easy at the top range of motion. The exercise was harder in the partial group because they didn’t have to lift through the top portion of the skull crusher. You can try this for yourself. When doing a lying barbell skull crusher, you can feel the top 45 degrees to be very easy, thus significantly unloading tension from the exercise.
  • The lying barbell skull crusher doesn’t take advantage of the stretched position. One of the advantages of full range reps is the stretched position where lots of muscle growth takes place. Unfortunately, this exercise doesn’t really take advantage of the stretched position taking away a crucial advantage in full range reps.
  • Because of these factors, the partial rep group was able to see higher muscle activation and much bigger muscle growth.

While I think the study design was poor and that lying barbell skull crushers aren’t a great triceps exercise anyways, it does indicate some exercises are better done with partials especially if you know which portion to optimally cut out.

Furthermore, a review on this topic discusses how hypertrophy is at the very least similar in many exercises using both full and partial along with partials having the use during rehab (11).

Another review found similar findings, full is best, but partials can be comparable at best (12).

Research is a bit mixed because it ultimately depends on the exercise. Some exercises where the most anabolic position (lengthened position) is underloaded. Thus, doing partials to overload this position can enhance growth on some exercises (9,13).

The Key Takeaways

Here’s everything summed up for you as an evidence based recap:

  • Full reps are best for power, but including partials will also be beneficial.
  • Full reps are best for strength especially strength across a greater range of motion, but partials should be included to strengthen specific ranges of weakness if need be especially for squats.
  • Full reps are best for hypertrophy, but including partial reps strategically for certain exercises can enhance hypertrophy. I’ll write a future article on how to include partials optimally.

Keep in mind, these are just general recommendations. Certain situations will not allow for full reps like specific injuries for example, but long story short, full reps should be your bread and butter. You should rarely sacrifice range of motion just for the sake of using more weight. In general, your bloodline is disgraced if you never train with a full range of motion.

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  1. “Comparative Effects of Deep Versus Shallow Squat and Leg-Press Training on Vertical Jumping Ability and Related Factors (English).” Comparative Effects of Deep Versus Shallow Squat and Leg – Technische Informationsbibliothek (TIB), www.tib.eu/en/search/id/BLSE%3ARN083862208/Comparative-Effects-of-Deep-Versus-Shallow-Squat/.
  2. Hartmann, Hagen, et al. “Influence of Squatting Depth on Jumping Performance.” Journal of Strength and Conditioning Research, U.S. National Library of Medicine, Dec. 2012, www.ncbi.nlm.nih.gov/pubmed/22344055.
  3. Pinto, Ronei S, et al. “Effect of Range of Motion on Muscle Strength and Thickness.” Journal of Strength and Conditioning Research, U.S. National Library of Medicine, Aug. 2012, www.ncbi.nlm.nih.gov/pubmed/22027847.
  4. Massey, C Dwayne, et al. “Influence of Range of Motion in Resistance Training in Women: Early Phase Adaptations.” Journal of Strength and Conditioning Research, U.S. National Library of Medicine, May 2005, www.ncbi.nlm.nih.gov/pubmed/15903383.
  5. Bazyler, Caleb D, et al. “The Efficacy of Incorporating Partial Squats in Maximal Strength Training.” Journal of Strength and Conditioning Research, U.S. National Library of Medicine, Nov. 2014, www.ncbi.nlm.nih.gov/pubmed/24662234.
  6. McMahon, Gerard E, et al. “Impact of Range of Motion during Ecologically Valid Resistance Training Protocols on Muscle Size, Subcutaneous Fat, and Strength.” Journal of Strength and Conditioning Research, U.S. National Library of Medicine, Jan. 2014, www.ncbi.nlm.nih.gov/pubmed/23629583.
  7. McMahon, Gerard, et al. “Muscular Adaptations and Insulin-like Growth Factor-1 Responses to Resistance Training Are Stretch-Mediated.” Muscle & Nerve, U.S. National Library of Medicine, Jan. 2014, www.ncbi.nlm.nih.gov/pubmed/23625461.
  8. Goto, Masahiro, et al. “Partial Range of Motion Exercise Is Effective for Facilitating Muscle Hypertrophy and Function Through Sustained Intramuscular Hypoxia in Young Trained Men.” Journal of Strength and Conditioning Research, U.S. National Library of Medicine, May 2019, www.ncbi.nlm.nih.gov/pubmed/31034463.
  9. Pedrosa. “Partial Range of Motion Training Elicits Favorable Improvements in Muscular Adaptations When Carried out at Long Muscle Lengths.” Taylor & Francis, https://www.tandfonline.com/doi/abs/10.1080/17461391.2021.1927199?journalCode=tejs20.

  10. Martínez-Cava, Alejandro, et al. “Bench Press at Full Range of Motion Produces Greater Neuromuscular Adaptations Than Partial Executions After Prolonged Resistance Training.” Journal of Strength and Conditioning Research, U.S. National Library of Medicine, 26 Sept. 2019, www.ncbi.nlm.nih.gov/pubmed/31567719.
  11. Lab, 1Exercise Physiology and Biochemistry. “Partial Compared with Full Range of Motion Resistance… : The Journal of Strength & Conditioning Research.” LWW, journals.lww.com/nsca-jscr/Fulltext/2018/09000/Partial_Compared_with_Full_Range_of_Motion.29.aspx.
  12. Schoenfeld, Brad J, and Jozo Grgic. “Effects of Range of Motion on Muscle Development during Resistance Training Interventions: A Systematic Review.” SAGE Open Medicine, SAGE Publications, 21 Jan. 2020, www.ncbi.nlm.nih.gov/pmc/articles/PMC6977096/.

  13. Sato, Shigeru, et al. “Elbow Joint Angles in Elbow Flexor Unilateral Resistance Exercise Training Determine Its Effects on Muscle Strength and Thickness of Trained and Non-Trained Arms.” Frontiers, Frontiers, 1 Jan. 1AD, https://www.frontiersin.org/articles/10.3389/fphys.2021.734509/full.

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