We have all witnessed someone in the gym who hasn’t exactly performed an exercise throughout its full range of motion (ROM).
Let me paint the picture…you watch someone in the corner of the gym getting psyching themselves up by screaming and slapping themselves, then proceeding to do 1200 lbs. for quarter reps on the leg press!
Afterwards, they jump up, fist pump their buddy and walk around with their hands in the air boasting that they leg pressed 1200 lbs. for reps...
If you didn’t know any better; you'd be in awe of this feat and astonished by the super human strength of this individual. As you walk back to the squat rack and perform full range of motion reps with a much lighter weight; you ponder if a set of partial reps with that much weight really is effective at building muscle and strength.
Let’s look at what the current evidence on ROM with the aim of making an informed choice on how you should train.
Background on range of motion
We know from research that resistance training is often reported as the most effective method for accomplishing long-term increases in strength and muscle mass (1).
Training variables most often discussed include volume (reps x sets), load/intensity (how much resistance used) and frequency (how often to train).
These variables affect mechanical stress over the muscle and, consequently, the magnitude of exercise induced muscle damage (2).
One variable that hasn’t received a whole of attention in controlled research is ROM, which is operationally defined as the degree of movement that occurs at a given joint during exercise performance (3).
Despite its relative lack of attention in the research literature, ROM can potentially play a crucial role in muscular adaptations.
There are some people that propose a full ROM is necessary to maximize the value of an exercise. In fact, most of the evidence demonstrates that strength adaptations are specific to the joint angles utilized.
Therefore, to optimize strength throughout a full ROM; one must train utilizing full ROM in their exercises, and findings from the available literature are consistent with the principle of specificity.
Essentially, this means that neural adaptations occur with persistent training specific to a given ROM (4).
Range of motion on strength
A recent study examined the effects of resistance training followed by a detraining period over a longer versus shorter ROM on structural and functional changes in the quadriceps muscle (5).
Significant adaptations in strength and size occurred in both longer and shorter ROM training groups across all muscle measurements. Interestingly, midthigh subcutaneous fat decreased to a greater extent after training at a longer ROM compared with a shorter ROM.
It is often very tempting for an athlete to decrease ROM in order to accommodate a heavier weight with the assumption that this will cause better muscular adaptations in strength and size. However, from the evidence presented in this study, this assumption would be incorrect.
In summary, this research showed that structural differences were larger and strength was enhanced to a greater extent after training with a longer versus shorter ROM.
This research demonstrates that resistance training protocols enforcing a longer ROM enhance the muscle characteristics that influence force and power production to a greater extent than protocols where ROM is not as extensive.
Another study compared partial versus full ROM upper body resistance training on strength and muscle thickness. Volunteers trained twice a week for 10 weeks in a periodized program. Results indicated that biceps strength significantly increased for both the full and partial ROM groups, but this was more pronounced in the full ROM group.
In addition, full ROM 1-repetition maximum (1-RM) strength was significantly greater than partial ROM 1-RM strength after the training period.
Average muscle thickness of the biceps significantly increased in both training groups. This study indicates that muscle strength and muscle thickness can be improved with both full and partial ROM resistance training, but full ROM leads to greater strength gains (6).
Range of motion and muscle damage
There is a lack of research regarding the acute effects of ROM on muscle damage induced by resistance training. Until recently, it was unknown whether heavier resistance utilized in a partial ROM or a larger joint angle experienced during a full-ROM exercise was more conducive for creating muscle damage.
A recent investigation examined the acute effect of a traditional resistance training exercise using full vs partial ROM on muscle damage makers. Participants completed 4 sets of 10 repetitions of a dumbbell bicep curl equal to 80% of their full or partial ROM 1-RM (7). Participants performed the curl exercise with one arm using a partial ROM and the other arm using a full ROM.
This is the first study that compared muscle damage in elbow flexors after a traditional resistance training session with different loads while comparing full vs partial ROM.
This research proved that heavier loads lifted for partial repetitions are not as effective as completing the exercise throughout its entire ROM.
Range of motion and muscle growth
It seems the evidence for training-induced variations in ROM on muscular strength is quite convincing, but its effect on muscle growth isn’t as clear.
There are currently two schools of thought, one school believes that completing an exercise throughout its full ROM produces greater stimulation of fibers by maximizing the shortening and lengthening of the fibers (8).
Another school believes partial ROM training allows the use of heavy loads in a muscles strongest range, which plausibly leads to greater long-term muscle growth (9).
A recent systematic review of the literature examined the effects of performing resistance exercise with a full versus partial ROM on changes in muscle growth (10).
Current research suggests that performing resistance training through a full ROM confers beneficial effects on muscle growth of the lower body musculature when compared with training with a partial ROM.
It seems that research on the effects of ROM on upper extremities is limited and conflicting, thereby preventing the ability to draw strong practical implications. There is no research that has investigated how ROM influences muscle growth of the trunk musculature.
Therefore, there is no compelling rationale for employing a given ROM versus another in the upper body muscles (10).
Below are some key take home points based on the current available research on ROM.
Important considerations and practical application
It’s crucial to remember that resistance training prescription does not have to be a binary choice and include only training with full or partial ROM. Another consideration in this regard is the ability to employ greater magnitudes of load during partial ROM training; consequently, amplifying mechanical tension on the target muscles.
Given that mechanical tension is purported to be the primary driver of resistance training-induced muscle growth; (11) it’s conceivable that performing some heavy training in a shortened ROM in combination with full ROM training may cause alterations in intracellular signaling that positively change long-term muscle protein growth. Although this hasn’t been directly investigated; it is a very plausible hypothesis.
Moreover, there is evidence that employing partial ROM training with heavy loads enhances the ability to use more weight during full range movements (12). Theoretically, this may serve to enhance muscle growth by increasing the amount of tension placed on muscles over time.
Exercise prescription considering ROM needs to consider the specific goals of the trainee/athlete (i.e., increase in strength at specific angles or at the entire ROM). For example, a basketball player may need to increase partial ROM in a squat because they don’t typically do a full squat when they go for a jump ball or rebound.
References:
1. Stone, M., Plisk, S., and Collins, D. (2002) Training principles: evaluation of modes and methods of resistance training--a coaching perspective. Sports Biomech 1, 79-103
2. Chen, T. C., and Nosaka, K. (2006) Responses of elbow flexors to two strenuous eccentric exercise bouts separated by three days. J Strength Cond Res 20, 108-116
3. Haff GG, T. N. e. (2015) Essentials of strength and conditioning 3rd ed., Human Kinetics, Champaign, IL
4. Kitai TA, S. D. (1989) Specificity of joint angle in isometric training. Eur J Appl Physiol Occup Physiol. 58, 744-748
5. McMahon, G. E., Morse, C. I., Burden, A., Winwood, K., and Onambele, G. L. (2014) Impact of range of motion during ecologically valid resistance training protocols on muscle size, subcutaneous fat, and strength. J Strength Cond Res 28, 245-255
6. Pinto, R. S., Gomes, N., Radaelli, R., Botton, C. E., Brown, L. E., and Bottaro, M. (2012) Effect of range of motion on muscle strength and thickness. J Strength Cond Res 26, 2140-2145
7. Baroni, B. M., Pompermayer, M. G., Cini, A., Peruzzolo, A. S., Radaelli, R., Brusco, C. M., and Pinto, R. S. (2017) Full Range of Motion Induces Greater Muscle Damage Than Partial Range of Motion in Elbow Flexion Exercise With Free Weights. J Strength Cond Res 31, 2223-2230
8. Fleck SJ, K. W. (2004) Designing resistance training programs, 3rd ed., Human Kinetics, Champaign, IL
9. Sisco P, L. J. (1997) Power factor training: a scientific approach to building lean muscle mass., Contemporary Books, Chicago, IL
10. Schoenfeld, B. J., and Grgic, J. (2020) Effects of range of motion on muscle development during resistance training interventions: A systematic review. SAGE Open Med 8, 2050312120901559
11. Schoenfeld, B. J. (2010) The mechanisms of muscle hypertrophy and their application to resistance training. J Strength Cond Res 24, 2857-2872
12. Bazyler, C. D., Sato, K., Wassinger, C. A., Lamont, H. S., and Stone, M. H. (2014) The efficacy of incorporating partial squats in maximal strength training. J Strength Cond Res 28, 3024-3032
