If you follow professional bodybuilders, you’ve noticed that most of them (if not all) do not use full range of motion (ROM). Whether their benching, squatting, doing some curls or rows, they never go to a full stretch nor lockout each rep at the top. Their intent is to keep “constant tension” in the muscle. However, in evidence-based circles, full ROM training is generally advisable. So, who’s right? The purpose of this article is to compare full vs. partial ROM training for hypertrophy and give you some practical applications.
First, some definitions: most people think of ROM as the distance traveled by the weight. However, “ROM is defined as the amount of movement about a joint, which is dependent upon the joint articulation, classification, and the plane or axis the action takes place” , and is measured in degrees. “The ROM related to skeletal muscle has been termed “functional excursion” which is defined as a muscle from a position of a full stretch to a position of maximal concentric contraction that is directly influenced by the joint it crosses” . For muscle growth, functional excursion (the length of the muscle and how it changes) is what we care about, but since we cannot observe it in practice, we use ROM as a proxy .
For example, think of the movement of elbow flexion (like when you’re doing bicep curls). Full ROM would have the bicep go from a full stretch to a maximal contraction, which would be from 0º (full elbow extension) to ~140º of elbow flexion. Partial ROM would be any specific ROM within the full ROM spectrum (e.g. 30-100º).
Before we take a look at each individual study, I think it’s useful to make a distinction between 2 categories of studies:
1st Category: studies that compare a group doing full ROM vs. a group doing just the top portion of the movement (e.g. full squats vs. quarter squats).
2nd Category: studies that compare a group doing full ROM vs. a group doing the middle portion of the ROM (keeping “constant tension”, not going all the way down nor locking out each rep at the top).
Overall, I found 6 individual studies and one systematic review. In the 1st Category, we have 4 studies:
McMahon et al.  compared one group doing a ROM of 0-90º of knee flexion vs. another group doing a ROM of 0-50º of knee flexion on various exercises for the quadriceps. The authors measured muscle growth in 3 different sites (25%, 50% and 75% of femur length) of the vastus lateralis (one of the muscles of the quadriceps) and found that there was a trend for better gains in favor of the full ROM group and that the differences between groups were significant at 75% of femur length in favor of the full ROM group. This suggests that this group had a more uniform growth of the vastus lateralis. The authors also found that, following a detraining period, the full ROM group maintained their gains for longer.
Bloomquist et al.  compared deep squats (0-120º of knee flexion) vs. shallow squats (0-60º of knee flexion). Similar to the previous study, this one showed greater increases in quadriceps muscle size and more uniform growth across the muscle for the deep squats group.
Kubo et al.  compared Full Squats (0-140º knee flexion) vs. Half Squats (0-90º knee flexion). The results showed no differences in quadriceps size between groups (maybe because the partial ROM group used a relatively high ROM, equivalent to the ROM used by the full ROM group in the first study). However, increases in adductor and gluteus maximus muscle size were significantly greater in the Full Squat group. This suggests that full squats might be better for hypertrophy of the adductors and gluteus maximus.
Valamatos et al.  compared full ROM (0-100º of knee flexion) vs. partial ROM (0-60º of knee flexion) knee extensions. The training program consisted of concentric-only knee extensions on a dynamometer. For every subject, one of the legs did full ROM and the other did partial ROM. Results showed no differences between groups for increases in muscle size.
Overall, two studies [3,4] showed better gains in the full ROM group, and the other two [5,6] showed no differences (one used a relatively high ROM for the partial ROM group; the other used concentric-only training). Also, two of those studies [3,4] showed that, in the group doing full ROM, hypertrophy of the vastus lateralis was more evenly spread across the entire length of the muscle. This finding is supported by another study by McMahon et al.  and suggests that, when using full ROM, you will probably stimulate different regions of the muscle, which will translate in a more uniform growth across the entire length of the muscle. There’s also evidence that full ROM training will conserve your gains for longer if, for whatever reason, you stop training [3,7]. For all those reasons, using full ROM might be better for quadriceps hypertrophy and should be prioritized over just doing the top half of any given movement. This is in line with the results of the systematic review by Schoenfeld & Grgic  that concluded that “for lower body musculature, there appears to be a benefit to training with a full ROM”.
For the 2nd Category, I found 2 studies. Let’s take a look at them:
Pinto et al.  compared full ROM (0-130º of elbow flexion) vs partial ROM (50-100º of elbow flexion) on bilateral preacher curls. Results show better results in increases in muscle size for the full ROM group when compared to the partial ROM group (the differences were not significant), suggesting that full ROM might be better than partial ROM.
Goto et al.  compared full ROM (0-120º of elbow extension) vs. partial ROM (45-90º of elbow extension) on barbell lying elbow extensions. Results show more muscle gain in the partial ROM group, when compared to the full ROM group. However, the increases in triceps muscle size were freakishly big (~49% for the partial ROM and ~28% for the full ROM groups). These increases are way bigger than what we’re accustomed to see in resistance training studies (5-10%), especially when we consider that the study lasted 8 weeks and was done on trained individuals.
Overall, we have two studies, both on upper body muscles: one showed better gains with full ROM; the other, the exact opposite. Therefore, we can’t have a clear idea of what’s better. That’s also the conclusions of the systematic review by Schoenfeld & Grgic , where the authors stated that “for the upper body, the evidence is less conclusive”. However, there’s an interesting perspective I want to share with you.
Greg Nuckols reviewed the study by Goto et al.  in Monthly Applications in Strength Sport (MASS)  and stated that, probably, what matters the most is not the full ROM per se, but making sure you train through long muscle lengths. A study by McMahon et al.  supports this point of view, by showing that training with partial ROM but at longer muscle lengths (40-90º of knee flexion on back squats) resulted in similar hypertrophy when compared to training through a “full ROM” (0-90º of knee flexion) and that both training styles were superior to training with a partial ROM but at shorter muscle lengths (0-50º of knee flexion).
In his review , Greg goes on to say that the least challenging parts of a movement’s ROM are potentially unnecessary or possibly even counterproductive for hypertrophy, assuming they occur at a short muscle length for the prime movers. This means that the ROM you should use will depend on the exercise you’re doing. For most pressing movements (bench press, overhead press, squat, leg press, etc.), the lockout is usually really easy and it’s where the prime movers are in the most shortened position, so ending each rep just before lockout will probably not make much of a difference for hypertrophy. On the other side, for most pulling movements, when the bar is the closest to your body, is when the prime movers are in the most shortened position. However, this is also the most challenging part of the movement (the sticking point), and you always want to train through the sticking point, so that you maximize the tension applied to the target muscles . Therefore, you might not want to chop off the top part of the ROM in pulling movements.
All of this means the ROM you use will depend on the exercise you’re doing, particularly where’s the least challenging part of the movement and does that correspond to a shortened position of the prime mover. However, I have to say that we’re not sure this is how things work, we still need a lot more studies on this topic to draw solid conclusions.
I will make one final point in favor of full ROM training: training through a full ROM (and, therefore, having well-defined start and end points for each movement), will help you standardize your technique and, in my opinion, that’s an important aspect for assessing progress in the gym. If, when you bench, you only lower the bar mid-way, in the final reps you might be tempted to shorten them even more so that you feel like you’ve progressed from the previous training session. However, this doesn’t mean you’ve progressed, you’re only cheating yourself. Instead, if you touch your chest each time you lower the bar, there’s no room for cheating and you’ll actually know if you’ve progressed or not.
Now, there’s also situations where you probably shouldn’t use full ROM. Despite most results showing full ROM might be better for hypertrophy (at least for lower body exercises), it shouldn’t be put on a pedestal. What I mean by that is that you should not sacrifice safety for extra ROM. If you squat below parallel with good form, I think it’s not a good idea to go ass-to-grass if your lumbar has to round a lot to achieve that position. Also, if using full ROM causes you consistent joint or connective tissue pain in a lot of similar exercises (e.g. you have a lot of shoulder pain if you go all the way down in the bench press, whether you use barbell, dumbbells or cables, and whether you do it on a flat, incline or decline bench), you might consider not using full ROM on those exercises. If you only feel pain when doing one variation, I think the best bet is to avoid that exercise and choose another that works the muscle in a similar way and where you can do full ROM pain free.
Full ROM training is a good default strategy, but it’s probably not mandatory for EVERY exercise.
When doing exercises for the quadriceps, prioritize full ROM training. This seems to be better not only for hypertrophy of the quadriceps, but also for hypertrophy of adductors and gluteus maximus (in compound movements).
Always work through the sticking point.
You can eliminate the top part of a movement if a) the prime mover is at a shortened position and b) that part of the ROM is the least challenging.
Prioritize safety over ROM. Do not put yourself in “dangerous” situations just to get a bit of extra ROM.
If using full ROM hurts your joints and/or connective tissue on a category of movements, you might be better off cutting off some of the ROM.
 Newmire DE, Willoughby DS. Partial compared with full range of motion resistance training for muscle hypertrophy: A brief review and an identification of potential mechanisms. J Strength Cond Res [Internet]. 2018 Sep [cited 2020 Feb 5];32(9):2652-2664. Available from: https://journals.lww.com/nsca-jscr/Pages/articleviewer.aspx?year=2018&issue=09000&article=00029&type=Fulltext
 Henselmans M. 2018. Henselmans Online PT Course. Available from: https://mennohenselmans.com/online-pt-course/
 McMahon GE, Morse CI, Burden A, Winwood K, Onambélé GL. Impact of range of motion during ecologically valid resistance training protocols on muscle size, subcutaneous fat, and strength. J Strength Cond Res [Internet]. 2014 Jan [cited 2020 Feb 7];28(1):245-55. Available from: https://www.researchgate.net/publication/236581117
 Bloomquist K, Langberg H, Karlsen S, Madsgaard S, Boesen M, Raastad T. Effect of range of motion in heavy load squatting on muscle and tendon adaptations. Eur J Appl Physiol [Internet]. 2013 Aug [cited 2020 Feb 18];113(8):2133-42. Available from: https://www.researchgate.net/publication/236253394
 Kubo K, Ikebukuro T, Yata H. Effects of squat training with different depths on lower limb muscle volumes. Eur J Appl Physiol [Internet]. 2019 Sep [cited 2020 Feb 7];119(9):1933-1942. Available from: https://highfit.com.br/wp-content/uploads/2019/06/KEITARO-KUBO-2019.pdf
 Valamatos MJ, Tavares F, Santos RM, Veloso AP, Mil-Homens P. Influence of full range of motion vs. equalized partial range of motion training on muscle architecture and mechanical properties. Eur J Appl Physiol [Internet]. 2018 Sep [cited 2020 Feb 6];118(9):1969-1983. Available from: https://www.researchgate.net/publication/30612012
 McMahon GE, Onambélé-Pearson GL, Morse CI, Burden AM, Winwood K. Electrodiagnosis in New Frontiers of Clinical Research. InTechOpen; 2013. Chapter 8, How deep should you squat to maximise a holistic training response? Electromyographic, energetic, cardiovascular, hypertrophic and mechanical evidence; p. 155-74.
 Schoenfeld BJ, Grgic J. Effects of range of motion on muscle development during resistance training interventions: A systematic review. SAGE Open Med [Internet]. 2020 Jan [cited 2020 Mar 1];8:2050312120901559. Available from: https://www.researchgate.net/publication/338230558
 Pinto RS, Gomes N, Radaelli R, Botton CE, Brown LE, Bottaro M. Effect of range of motion on muscle strength and thickness. J Strength Cond Res [Internet]. 2012 Aug [cited 2020 Feb 5];26(8):2140-5. Available from: https://www.researchgate.net/publication/233634491
 Goto M, Maeda C, Hirayama T, Terada S, Nirengi S, Kurosawa Y, et al. Partial range of motion exercise is effective for facilitating muscle hypertrophy and function through sustained intramuscular hypoxia in young trained men. J Strength Cond Res [Internet]. 2017 May [cited 2020 Feb 5];33(5):1286-1294. Available from: https://www.ncbi.nlm.nih.gov/pubmed/31034463
 Helms E, Nuckols G, Zourdos M, Trexler E. Monthly Applications in Strength Sport Research Review; Volume 4, Issue 3. Available from: https://www.strongerbyscience.com/mass/