Curious Case of Range of Motion
It’s very easy to find people in your gym, not practicing full range of motion, especially in exercises like “Bench Press and Leg Press”, further, we also see various elite level IFBB pro-bodybuilders practicing partial range of motion. For those who are novice and don’t understand what is range of motion. A range of motion is a measurement of movement potential of any exercise. Example, a full range of motion in a bench press will be bringing the bar all the way down to where it touches your area between chest and upper abdominal and to all the way up where your elbows get locked, whereas a partial range of motion will be where you are not coming all the way down or when you are not locking your elbows. Now fundamentally, compromising on range of motion is something which should be non-negotiable irrespective of whether you are performing isolation or compound movement. however, there are many expert trainers/youtubers/bodybuilders, who promote/practice partial range of motion under a theory to keep constant tension on the muscle (higher time under tension). As per the literature, there are notable three studies available with different sample size performing different set of exercises, out of which two suggest that practicing full range of motion lead to maximum muscle hypertrophy. (Studies: https://www.ncbi.nlm.nih.gov/pubmed/22027847, https://www.ncbi.nlm.nih.gov/pubmed/29982844/, https://www.ncbi.nlm.nih.gov/pubmed/31034463) Interestingly, from above studies, latest one is by Goto & Colleagues, which found greater hypertrophy gains, performing partial range of motion while doing triceps extension exercise. However, reviewing that study, under publication of MASS, a very popular scientist Greg Nuckles quotes “shortening the ROM may not provide an advantage for many machine or cable exercises that allow for constant tension through the entire range of motion. If you want to implement this style of training for hypertrophy purposes, I’d recommend don’t chop off too much of range of motion” So, I would say that it would always be better and safer choice to have a full range of motion as a primary parameter of your training, rather than exploring the exercises where you can afford partial range of motions by trial and error. Further, more than scientific literature, I personally believe that implementing full range of motion, also helps us keep our ego lifting aside and reduce injury risk as well. Continuing with bench press example, imagine you doing 10 reps of 60 kgs with partial range of motion, where you are bringing bar all the way down to 80% of the distance between your chest and elbow lock out, and you progressive overload to 70 kgs for 10 reps, you won’t have any mechanism to know whether at 70kgs, you are still covering that distance of 80% or it has come down to 70%. Thereby practically, offsetting your increasing in total work done (which is nothing but training volume). However, had you practiced bench press at full distance between chest and elbow lockout, you might have progressed to 65 kgs, but still there are good chances qualitative amount of work done would still have been more than 70 kgs of partial reps. So, to conclude, in spite of conflicting literature, I would say it’s always optimal, to practice full Range of motion to maximize the muscle gains. Cheers Praveen P.S. Please Note range of motion here is being discussed purely from a muscle hypertrophy perspective, any sport specific implementation of partial range of motion to enhance the neuro muscular adaptation is a different thing.