Partial/Variable ROMS = Muscle Growth
- 09-03-2008, 09:51 PM
Partial/Variable ROMS = Muscle Growth
This topic started on another forum with a Phil Hernon post and as is often the case my science got lost and the discussion never really was about the original topic:
Partial & Variable Range of Motion (ROM) movements are "superior" to full ROMs
- Jay Cutler & Ronnie Coleman use bad form but hey if it works for them (gentetic freaks)... for everyone else its just cheating;
- You must touch the bar to your chest when you bench press...ass to grass or you're legs will be twigs...etc.;
- Partial ROMs will weaken your full ROM strength;
- Full ROMs are superior to partial ROMs if overall strength is the goal and if hypertrophy is the goal.
The truth is that if you use heavy weight, over a partial range of movement, such that you keep constant tension on THE target muscle for a sufficient duration AND lift with an explosive concentric such that maximium force is generated your muscles will grow*.
* - as long as you eat sufficiently for recovey & growth, don't overly tax the CNS, lift with enough frequency that anabolism outpaces catabolism, etc.
An Examination of Strength and Concentric Work Ratios During Variable Range of Motion Training, Ross A Clark, Adam L Bryant, and Brendan Humphries, J Strength Cond Res, August 14, 2008
Variable range of motion (ROM) training consists of partial ROM resistance training with the countermovement being performed at a different phase of the movement for each set. In this study, we assessed the effect of this method of training on peak force, load lifted, and concentric work performed.
Six male subjects with resistance training backgrounds (age 20.2 +/- 1.3 years, height 179.4 +/- 4.6 cm, weight 89.6 +/- 9.9 kg, 6-repetition maximum [6RM] bench press 92.5 +/- 14.3 kg) participated in this study.
Testing consisted of 6RM bench press strength tests during full (FULL), three quarter ((3/4)), one half ((1/2)), and one quarter ((1/4)) ROM from full elbow extension bench press performed on a Smith machine. The 6RM load, peak force (PF), and concentric work (W) performed during each ROM was examined using a one-way analysis of variance performed at an alpha level of p < 0.05.
The 6RM load increased significantly as the ROM was decreased for all tests (FULL = 92.5 +/- 14.3 kg, (3/4) = 102.1 +/- 14.3 kg, (1/2) = 123.3 +/- 23.6 kg, (1/4) = 160.9 +/- 26.2 kg). PF during each test was significantly higher during the (1/4) (1924.8 +/- 557.9 N) and (1/2) (1859.4 +/- 317.1 N) ROM from full elbow extension bench press when compared with the (3/4) (1242.2 +/- 254.6 N) and FULL (1200.5 +/- 252.5 N) ROM exercise. Although higher force levels were evident, the restriction in barbell displacement resulted in a subsequent reduction in W as the lifting ROM was reduced. These results suggest that variable ROM resistance training results in increased force production as the ROM diminishes.
So Load and Peak Force go up as ROM goes down. But as you reduce the bar displacement the Work goes down...so you would need to do more work (i.e. reps) to equal the full ROM's concentric work level.
Resistance training modes: specificity and effectiveness, MC Morrissey, EA Harman, and MJ Johnson, Med Sci Sports Exerc, May 1, 1995; 27(5): 648-60.
There is considerable demand for information on the effectiveness of various resistance exercises for improving physical performance, and on how exercise programs must match functional activities to produce the greatest performance gains (training specificity). Evidence supports exercise-type specificity; the greatest training effects occur when the same exercise type is used for both testing and training.
Range-of-motion (ROM) specificity is supported; strength improvements are greatest at the exercised joint angles, with enough carryover to strengthen ROMs precluded from direct training due to injury. Velocity specificity is supported; strength gains are consistently greatest at the training velocity, with some carryover.
Some studies have produced a training effect only for velocities at and below the training velocity while others have produced effects around the training velocity. The little, mainly isokinetic, evidence comparing different exercise velocities for improving functional performance suggests that faster exercise best improves fast athletic movements. Yet isometric exercise can improve actions like the vertical jump, which begin slowly.
The rate of force application may be more important in training than actual movement speed. More research is needed into the specificity and efficacy of resistance exercise. Test populations should include both males and females of various ages and rehabilitation patients.
Spectral EMG changes in vastus medialis muscle following short range of motion isokinetic training, Y Barak, M Ayalon, and Z Dvir, J Electromyogr Kinesiol, Oct 2006; 16(5): 403-12
This study was aimed at exploring the carryover effect of short range of motion (RoM) isokinetic conditioning on vastus medialis (VM) motor unit recruitment (MUR) across the full RoM. Fifty-five women were randomly assigned to one of four groups: G1 (n = 14) and G2 (n = 14) trained concentrically at 30 and 90°/s, respectively whereas G3 (n = 13) and G4 (n = 14) trained similarly but using the eccentric mode. All 4 groups trained within 30–60° of knee flexion.
The training protocol consisted of 4 sets of 10 maximal repetitions, 3 times a week for 6 weeks. sEMG was recorded from the VM for analysis of mean frequency of the EMG power spectrum prior to the training period and 2 days after its termination. The EMG assessments took place during dynamic contractions within 3 angular RoM’s: 85–60° (R1), 60–30° (R2) and 30–5° (R3). In addition MUR was evaluated during isometric contractions at 10°, 45° and 80°.
Significant increases were observed in the MUR at R1, R2, and R3 during dynamic contractions as well as in all 3 angles during isometric contractions. These findings applied equally regardless of the mode of contraction and motion speed during training.
The fact that MUR increased significantly within untrained RoM’s may point out to the potential benefits of short RoM conditioning, particularly in those cases where, during specific phases of rehabilitation, a wider RoM may be contraindicative.
So there is a carryover effect of increasing strength in the untrained upper and lower ROMs.
Overcoming the limitations of full ROM resistance training: The effects of variable ROM training on performance, activation, stiffness and muscle architecture, R. Clark, Journal of Science and Medicine in Sport, Volume 9, Supplement 1, December 2006, Page 24
Traditional full ROM resistance training has a number of limitations when used for training athletes. These include terminal deceleration, limited eccentric overload and a non-specific countermovement position. This study examined the effect of a variable ROM training program, consisting of partial ROM training with countermovements performed at a different ROM for each set, on upper body ballistic, isokinetic and isometric strength as well as musculotendinous stiffness, neuromuscular activation and muscle architecture using ultrasound.
Twenty-two semi-professional rugby league players were assigned to either a variable ROM (VROM) or full ROM (CON) 5 week training program, with both protocols equalised for concentric work. Testing consisted of isokinetic bench press throughout both the full ROM and half ROM from full extension, isometric strength and EMG at one quarter intervals throughout the bench press ROM, bench throws performed both with and without elastic energy contribution, upper body musculotendinous stiffness and pennation angles and muscle thickness of the long and medial head of the triceps brachii using ultrasound.
Testing revealed that the VROM group significantly improved a number of performance factors such as bench throw height and isokinetic peak force in comparison with the CON group. The results also suggest that VROM training also produces beneficial adaptations to the force/ROM curve. Therefore, this method of training appears to provide beneficial performance adaptations in athletes with extensive resistance training backgrounds, and may provide superior sports specific performance gains when used intermittently in an athletes training program.
There is value in varying the band of partial range movement...within a training session or between training sessions.
The load & force generated is higher when you do partials of say 1/2 ROM. The tension stays on the muscle targeted unlike full ROMs which take tension off/or shift the target muscle at the extremes of full ROMs. Strength is increased along the full range. There is less strain on connective tissue.
The only caveat is that overall work will decrease which may be restored simply by adding a rep or three.
- 09-03-2008, 11:32 PM
Poliquin was big on tut training right?
Those studies have piqued my interest...I may need to look into this more...
- 09-04-2008, 05:56 AM
I stumbled on to it many years ago in doing chest presses. I'd stop before my shoulders became heavily involved at the bottom and I'd stop before the triceps took over to finish the movement.
I used heavy weight and forceful concentric movement with simply a controlled negative. There really was no TUT in the sense of x seconds up x seconds down...it was just continous, serious tension on my pecs as I tried to move what at the time was heavy dumbells in "piston-like" fashion.
Rep ranges were no fewer than 8, no more than 12.
The motion was similiar to :bb3:
09-04-2008, 12:06 PM
09-04-2008, 12:39 PM
Really makes me wonder if it would help my bench. It is one of the few things I struggle to put up more weight on. I think I do have the stigma of having to go all the way down. I admit that I hate seeing people do the 4 inches above the chest bench though just because I know they couldn't get the weight up had they gone all the way down.
09-04-2008, 09:10 PM
Plus with dumbells you choose a heavy weight (one you can do proper ROMS in the 8-12 rep range) but that weight is one you still will have to do almost a full initial rep just to get them in place.
When I started doing this type of press years ago my chest grew at a much faster rate AND I have had NO shoulder problems since then.
Where you bring the dumbell down or BB down depends on the length of your arms, primarily forearms or ratio between upper and lower arm. Basically there is a point where you can feel some of the emphasis shift to your shoulders. Once you are familiar with THAT point you make sure your ROM stops just short of it.
For the top range just start by remembering not to lock out...eventually you'll find the right spot.
Here's how to do it:
09-04-2008, 09:18 PM
I strictly use the shorter ROM for my BB Incline Press for the shoulder saving aspects. Works great.
One thing I have noticed about pros and BB pressing is that their grip seems closer then your typical gym goer. Just something I have noticed in all the vids...
09-04-2008, 10:20 PM
Good advice. I had used the DB's on and off with the BB but I can see it being eaiser to break that not touching chest stigma with DB's. What I really need to do is pick up the DB's and stick with them! I keep getting drawn back to the BB but it is jsut not worth it haha.
09-04-2008, 11:22 PM
09-04-2008, 11:25 PM
Strength and Conditioning Journal
Article: pp. 10–14 | Abstract
Volume 29, Issue 5 (October 2007)
The Affect of Grip Width on Bench Press Performance and Risk of Injury
Carly M. Green, CSCS1, 3 and Paul Comfort, MSc, CSCS2, 4
1. Sports Injury Specialist Clinic, Gidea Park, Romford, United Kingdom, 2. London Sports Institute, Middlesex University, Queensway, Enfield, London, United Kingdom, 3. Carly M. Green is a Graduate Sports Rehabilitator, Strength and Conditioning Coach, and the Founder and Director of Sports Injury Specialist Clinic (SISC), 4. Paul Comfort is a Senior Lecturer and Strength and Conditioning Coach, London Sports Institute, Middlesex University
Bodybuilders, athletes, and recreational lifters select a grip width during the bench press that they believe will produce a greater force output. Research has demonstrated that a wide grip (>1.5 biacromial width) may increase the risk of shoulder injury, including anterior shoulder instability, atraumatic osteolysis of distal clavicle, and pectoralis major rupture. Reducing grip width to ≤1.5 biacromial width appears to reduce this risk and does not affect muscle recruitment patterns, only resulting in a ±5% difference in one repetition maximum.
Keywords: bench press, injury, performance, glenohumeral joint, pectorialis major
09-06-2008, 08:18 PM
Partial range of motion is a good shocking technique, giving the muscle a task it's not used to. Such as the one-and-a-half method, in which you perform one full rep, followed by a half rep, and so forth. By employing techniques to keep the muscles guessing, you're increasing intensity.
09-06-2008, 08:27 PM
09-06-2008, 08:38 PM
Electromyographic results showed that grip width did not significantly affect activity of the sternocostal head of the pectorialis major (p > 0.05). However, the narrow grip significantly increased the activity of the clavicular head (p < 0.01) and the activity of the triceps brachii (p < 0.05) compared to the wide grip (3, 12).
This is an area that is underdeveloped in most guys. Good objective information on how to directly work that upper area.
Especially since they also say "Research has also demonstrated that the level of inclination does not alter activation of the clavicular (upper) portion of the pectorals..."
So it is the narrow grip more than inclination that hits that area. Although my experience leads me to disagree on their incline statement...
Also note in the recommendations this reference by citation:
"It has been suggested that the descent phase should finish 4–6 cm above the chest (11)"
(11) HAUPT, H.A. Upper extremity injuries associated with strength training. Clin Sports Med. 20:481–491. 2001.
Again DON'T LET THOSE ELBOWS DROP BELOW PARALLEL.
09-06-2008, 08:53 PM
There are plenty of "Weider Principles" that one could use as intensifying techniques.
Let me ask you something. If partial ranges of motion generate more force & load then full ranges...and if full ROMs take the tension off of the muscle worked at the extremes why would you bring up the "one-and-a-half method, in which you perform one full rep, followed by a half rep"?
Shocking techniques, increasing intensity, one-and-a-half method...?
When I read that you have relegated partial ROMS to merely "a good shocking technique" I know you don't know what you're talking about. Just some more bullsh1t phrases anyone could find on just about any fitness board I suppose.
09-07-2008, 06:08 PM
Ok.. so I genuinely want to learn and understand this method. Without getting defensive, I have a few questions for you Dat.
As in all exercises, it is necessary to stretch the working muscle so that a contraction response can be elicited. Does the variable ROM method only apply to bench press?
How would you apply it to something like a bicep curl or tricep extension or a lateral raise?
(this is more of a comment)
Part of the function of a bench press is to work all of the upper body including the triceps, shoulders and chest. That is how we are able to lift such heavy weight in a bench press.. synergistic muscles.
Instead of removing synergistic muscles, why not correct the tight fascia causing the improper technique which has been pounded into our bodies by our ways of life?
If the athlete is unable to recruit the pectorals properly during a full ROM.. shortening their ROM is good?
By stimulating the GTO's of the pectorals, anterior deltoid, and triceps.. the muscles will have no further choice than to respond by growing and getting stronger while reducing the strain on the tendons.
09-07-2008, 10:47 PM
SynergyCSCS! I just responded to you in the other thread BEFORE I saw this.
Cool. Wow bro you do have a curious mind. I'm happy not because you might end up agreeing with me (who cares about that) but it turns out you are someone who will think about things & consider them. Very cool.
Extreme stretch - NO. Full stretch - No. More than a static hold - YES.Originally Posted by SynergyCSCS
No it applies to everything. You've probably done 21s for biceps before.Originally Posted by SynergyCSCS
Unless you really know what you are doing I'd avoid applying this to deadlifts.
Also you need to think about what you want to accomplish if you use it on squats. You need to think about the point of transition where the emphasis shifts from the quads to the hams & glutes and determine which ranges will effectively target the area. For me the biomechanics of partial ROMs on squats are too difficult so when I do squats I just do regular fuller range non-lock outs...
Plus we have all seen the skinny kid load a lot of weight on the squat bar and then do "partials" in the top range....THAT is NOT what we are talking about here...
I prefer to use partials for quads on exercises I can REALLY focus on like Staggered Leg Press (described below)
Your low leg is there only to stabilise, so it's essentially doing about 20% of the work compared to the high leg.
The foot position of the low leg means that the knee only passes through the middle third of it's ROM so it gets no rest. when you switch foot positions half way through the set, the medialis on the leg that was low & is now high will be screaming in agony by rep 4 or 5.
Lateral Raises are my specialty. My caps are really wide and this is the simple way I do them using this method.Originally Posted by SynergyCSCS
I lean the opposite way. If I want to be really strict I'd lay sideways on an incline bench ...but ususally I just lean on the preacher curl pad.
At the bottom position I never touch my side, which is leaning away, so the DB starts the upward movement always fighting gravity...and the tension stays on the shoulder cap.
Drop sets work well here...
The positioning looks similar to this:
Bicep curls ...you keep those elbows back...even behind your torso. You will not be able to curl much above the nipple line...elbows stay back and the tension stays on the bicep the entire time. There is no break at the bottom or top.
Biceps are a bit different...they actually need to work in a stretched position sometimes.
So also sometimes choose an exersise such as preachers where the tension is on the bicep when it is extended and work that lower 1/3. Preacher curls where you keep the tension on the bicep where you just work the lowere third hurts really good.
Triceps...simply come close to locking out but don't.
Actually any exercise including bench press should just be viewed as a tool... a means to an end.Originally Posted by SynergyCSCS
I don't work "bench press" I work my chest. My goal will NEVER be to lift ever increasing weights on an exercise that fails to maxamize hypertrophy.
I have made that mistake before...gotten mesmorized by the the opportunity to constantly add poundages to the bar...that is why many of my AAS steroid cycles failed to give me the mass I should have gained from putting my body through hormonal flux.
First of all I am using the bench press to work my chest NOT my triceps, Not my shoulders.Originally Posted by SynergyCSCS
I use straps when I do deadlifts because I am not deadlifting to strengthen my forearms. My relatively weak forearms should not limit the development of my strong by comparison back.
The same thing with the pecs. Forcing the range of motion into positions that take tension off of the pec and onto either the shoulders and triceps gives the pecs a break (i.e. lessens/removes the tension).
It is not easier on the chest to work the middle range of bench press motion it is HARDER (provided you do the same amount of work)!
If you have short arms you may not ever experience what I am about to say. But for most people handing the load to the shoulders in the shoulders most vulnerable position is not a good thing.Originally Posted by SynergyCSCS
My shoulders actually really grew when I stopped the full ROM bench press and then properly worked shoulder presses.
I even do BB shoulder press behind the neck with ZERO rotator cuff problems (ROM never goes below earlobe level)...
...this is possible because my shoulders are not damaged from full ROM bench pressing.
09-07-2008, 11:08 PM
It should also be mentioned that a proper ROM varies for every person. For example, if you have long arms for your height (e.g. I have a 74' reach at a height of 70"), then you must alter either your ROM or grip. I have had to explain this to many people who claim that they cannot touch their chest even on light presses. To compensate, I recommend 1) narrowing their grip, 2) heavy stretching after the session is complete (this also increases microtrauma), and 3) properly training the antagonists.
Also, it seems that the POV on this topic is very different. One is focusing on the hypertrophy/aesthetic aspects of training while the other is looking more at the performance aspect.
M.Ed. Ex Phys
09-08-2008, 01:14 PM
09-08-2008, 01:27 PM
09-09-2008, 03:23 AM
I just made a post regarding much of what this thread is about...
I read the studys but none of them actually say that it was found partial ROM is superior to full ROM in terms of strength on the bench press, considering if one was to "max" the rep would have to be a full ROM rep. 0
I would maybe be inclined to believe that partial reps ie. 3/4 reps are superior for chest muslce hypertrophy, because it's focus is more on the chest muscle and less on the assisting muscles, for example you use a lot of tricep to do the final 1/4 lock out distance. However my question is which form is more effective in terms of strength gains, once again, considering that bench standards and competitions are judged on full ROM presses. if you never did that last 1/4 wouldn't your chest/bench suffer in development/strength?
09-09-2008, 05:56 AM
Briefly on my experience I get stronger working the middle 2/3 of DB chest presses as well as increased hypertrophy. I don't know if this strength carry's over because I never test it. The only "test" is that when I go up in DB weight lay back with the DB and after I'm set I press the DBs up for that first rep.
So I am stronger in that bottom 1/3 as I progress although I don't work it.
Now having said that I noticed among myself and others that size increases (especially if the process is fed with insulin) out pace strength increases.
In sport you need functional muscle. You may need speed, you may need agility, you may need power through full & awkward ranges of motion...in that case you need to work through movements that duplicate the movements of your sport.
Powerlifters use partials to strengthen or better condition themselves to certain aspects of a lift BUT they do not by any means use partials exclusively. That would be a mistake for sure.
So definitely I agree with what you and Rodja are saying ...I have no doubt that strength for a sport is better served by using full ROMS and partials only when injury prevents full ROM or specialty exercises/training.
But now if we are talking about bodybuilding and strength gains for a bodybuilder there are definitely strength gains. Almost every time I do dumbell presses in various gyms (and I do them as described in this thread) I ALWAYS have someone say to me "that's a lot weight..." ...and it is...but my shoulders aren't crying ...in fact I often go do seated barbell shoulder presses after chest (again mid 2/3 ROM) and the tension stays right on those shoulders...and they continue to strengthen over that worked ROM (and the carryover portions).
09-09-2008, 12:10 PM
09-09-2008, 12:23 PM
Very well done as always Dat; you are probably the most diligent researcher I have encountered on the boards!
Another exercise which benefits from Partial ROM is heavy Lat Pulldowns. One supinates the scapula to form the base of contraction, and only releases their arms to a 45 degree angle on the descent. This keeps the tension solely focused on the lats., as opposed to completely straightening the arms and shifting tension to the rhombs/anterior delt tie-in.
DB Rows as well: I do not touch the ground, and cannot understand why some do. I do, however, have the DB parallel to my chest on the ascension because that is my point of peak contraction sans force shifting.
Again though, great thread to dispel the 'Brolore' surrounding full reps.
If anybody is interested, Vince Gironda was a huge proponent of peak contraction!
09-09-2008, 09:29 PM
I also like to take time periods each year where I work on Parillo style fascia stretching (pump, extreme stectch & pose).
But to directly answer your question no I don't do full ROM bench or shoulder presses ...just partial ROMs.
Squat & deadlifts are different ...I always liked the feeling of power & I believe those two exercise accomplish a lot of things (hormonal release when I am natural, muscle groups working in concert, lower back strength and stability...)
I have propaganda in my head too. I have no problem overcoming it for presses but pullups for some reason are the hardest to get the "you're cheating" voice out of my head. Its a Physical Education teacher voice too...all whiny ...Shut Up...Shut Up! Note to self: turn Mudvayne up in my ear. I can still hear the voice!
09-09-2008, 09:38 PM
I KNOW that partial pullups and pulldowns really work. I am no stranger to scapula retractions either BUT I need to hear it again & again to keep from slipping into full ROMs (especially pullups).
You are spot on bro. The reason a lot of guys say they get a lot out of wide grip pullups is because that forces them by accident to get into the position you describe and although still not the ROM you describe they at least are forced into some sort of partial range only.
Good advice bro. Now I've got a Mullet voice inside my head to compete with the P.E. teacher voice ...who will win out? vs =
09-09-2008, 10:18 PM
Here is an easy way to conceptualize (for others in the thread):
Each lift is necessarily four quadrants in respects to both the ascension and descension; the initial phase (either starting to ascend or descend), two middle quadrants where the tension is the greatest (you are resisting the load the greatest and thereby applying the peak amount of force here), and the completion. By completing a full ROM -aside from the initial ascension on the first rep - you are relieving tension off the target muscle at two points, and diverting that kinetic energy to antagonist muscles, and joints.
Partial reps exclusively work the muscle during the two middle quadrants; ensuring peak force is continued throughout. They are not completed with poor form, but rather perfect form in a continuous motion such that tension on the target muscle remains constant.
09-11-2008, 12:51 PM
09-15-2008, 03:12 PM
this sounds interesting and im eager to try and go for the 'feel' and finding the right spot for myself.
however ive always thought partial ROM was the sure way to injure yourself and pulling muscle and such...partial ROM is new to me, so are there special stretches you should do? im still a bit nervous to try it as i have had an injury to my triceps earlier this year.
i grew up lifting and hearing about how partial ROM will make your muscle head shorter (something like that) and eventually it will tear easily. another myth?
that staggered leg press looks awesome by the way.
09-15-2008, 08:45 PM
There is less stress on joints and connective tissue so those injury points are not vulnerable.
By-the-way never do heavy stretching between sets as this will reduce the built up tension in the muscle and make you more vulnerable to injury as well as reduce your load capacity. Wait till after the workout if you do them.
Understandable that an injury would do that to your mind set. But what is it about locking out your triceps and stretching them beyond their work range that makes full ROM "safer"?Originally Posted by comacho
Wow...we are from different generations. I grew up worrying about the Soviet Union raining on missles my head & wacking off to my poster of Farah Fawcett:Originally Posted by comacho
...yep and its even more effective then it looks. The helper leg works at a completely different angle so it is almost like a superset.Originally Posted by comacho
I'll bet if you start out using that exercise for partials it WILL just feel right. I think you are visualizing squats and there is just too much going on in that exercise to do partials exactly right straight away.
09-16-2008, 03:16 PM
i will incorporate the partials to all my movements...but dammit its hard to visualize, i tried to do it in front of the mirror lastnight and i was sweating my ass off just to get the feel right, hopefully with weights it will feel better.
oh buddy, the joy of learning how to lift again,,,sh1t! ahahhaha
so any movement, skip out the beginning and the finishing movements right? focus the middle part of the movement and keep the tension there throughout...
should i search for partial ROMs on youtube for visual demo?lol
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