Geschatte leestijd: 19 minutenThe effect of negative training on muscle strength and muscle mass has been measured in various studies and has been found to be greater than the effect of concentric training. In this article, I explain the concepts of concentric training, eccentric training, and isometric training, discuss these studies, and describe their application in practice.
What is negative training
In gyms, the same discussions are often held. What do you eat and how much, which muscle groups do you train together and when, how many repetitions should you do, and how heavy? Even experienced strength trainers can discuss this endlessly. The fact that there are continuously new scientific insights promotes these discussions, also because experienced people sometimes talk about principles that were accepted decades ago but now turn out to be incorrect and outdated.
Often you see that these kinds of new developments penetrate slowly or not at all into the daily experience of fitness and bodybuilding in gyms. This is firstly because most people simply are not aware of it. That’s not strange either. Not everyone searches through scientific publications every day like the editors of this site for interesting studies. However, you also see in training courses for, for example, fitness instructors that many, now outdated, theories are still being taught.
The current principles of bodybuilding were developed in the 1930s through the 1960s by pioneers such as Joe Weider and later Arthur Jones (Nautilus equipment and promoter of HIT) and have hardly changed to this day. Compared to the revolution that has taken place in the field of nutrition and the enormous increase in (accepted) knowledge in that area, it is actually strange that we often still train the same as sixty years ago. The only difference is that the gyms are larger, offer more equipment (based on the same old principles), and look a lot slicker.
At the same time, it is very understandable that we stick to the old, proven methods. These have already proven themselves. Moreover, the greatest examples for many current (amateur and hobby) bodybuilders are not the mass monsters of today’s Mr. Olympia stage, but the men from the “golden age” of bodybuilding. Men like Steve Reeves, Frank Zane, Rich Gaspari, our own Berry de Mey, Ed Corney, and of course Arnold Schwarzenegger.
The thought: “If it worked for them…” is very understandable. On the other hand, traveling by horse and carriage worked fine in the past too. Yet I prefer to get into the car or the bus in the morning rather than having to brush and saddle a horse first. My daughter wouldn’t share that opinion.
More importantly: The results they achieved were due to a life dedicated to improving their own physique. Every day, every meal, every training session. Since most of us do not have this dedication and in many cases the talent, wouldn’t it be nice if there were ways to train more effectively based on current science to narrow the difference in results? One of the developments that has been accepted in medical and physiotherapeutic science but not fully in the world of bodybuilding is negative training, doing negative repetitions.
Although regularly applied, it is often used as an additional training form while according to several studies it should be the standard method of training.
Negative repetitions
Negative repetitions or negative training does not mean that you perform your training under the continuous mumbling of words like “everything sucks” and with a crappy mood. It is an expression that stands for emphasizing the eccentric movement of an exercise.
Negative training is the part of the exercise where the muscle is lengthened under tension, with or without relief from the load. For example, when bench pressing and you push the weight up, the chest muscle becomes shorter as it contracts.
When you lower the weight again, the muscle becomes longer. This latter part of the movement is called the eccentric part.
Eccentric training or doing negative repetitions means that you emphasize this part of the movement. The concentric part of the movement in this example is pushing the weight up where the muscle becomes shorter. This is the aspect on which most bodybuilders focus.
Isometric training involves static loading of the muscle. In the example of bench pressing, this could be when you have lowered the bar to just above the chest and hold it here, keeping the chest muscle tense with equal length of the muscle fibers.
Concentric, eccentric, and isometric
A well-executed exercise contains all three aspects. In practice, however, you often see that the emphasis is almost always on the concentric part and the eccentric and isometric parts are neglected.
To stick with the example of bench pressing: You often see that the bar is explosively pushed upwards (great!), but instead of making a stop above where the tension should be maintained, many people let the weight drop immediately without offering resistance (except the necessary resistance to prevent the bar from hitting their chest). Then, in one, almost bouncing, motion, it is pushed upwards again, again without stopping at the bottom of the movement. By not stopping the weight at the top and bottom of the movement, the isometric part of the exercise is not performed. Worse yet, by letting the weight fall down instead of lowering it under control, the eccentric part is also skipped. There are two main reasons why this is practiced by many people in practice.
Heavy Training Isn’t the Same as Training with Heavy Weights!
In “A day in the life of,” Kai Greene discusses his annoyance with the fact that many bodybuilders recording DVDs use exaggeratedly heavy weights, more than they would normally use. He calls this “ego-lifting” (and subtly refers to Ronnie Coleman who, for his DVD, loaded so many plates onto the leg press that his trainer was concerned the bar might break). Ego-lifting happens in every gym, consciously and unconsciously. In these cases, weight comes at the expense of proper execution.
Bench pressing is much easier when you let the bar fall back and push it back up in one fluid motion. Thus, you can press much more than if you hold the weight steady both up and down and slowly and controlledly lower it.
Too many people are focused on how heavy they can lift. Any pro will tell you, “It’s not about the weights!” In powerlifting, it’s about making it easy to lift a weight by improving technique. In bodybuilding and fitness, it’s exactly the opposite, and good technique indicates your ability to make it as heavy as possible with as little weight before adding weight.
For the layman, this is less impressive than throwing around heavy weights, but to the experienced strength athlete, you don’t really impress by using your whole body like a monkey to lift a weight much heavier than it should be, instead of, for example, just using your biceps. The faster you train as you should train, the faster you see results. The faster you don’t give a damn anymore when you’re doing a super heavy execution of an exercise with baby weights because your body speaks for itself.
At most, people will wonder why someone with such a muscular physique is “lightly” training and then wonder if those heavy weights are always necessary.
Ignorance
More and more gyms operate on the basic principle of paying as low a membership fee as possible but not getting guidance. This is ideal for experienced athletes who don’t want to spend money on fitness instructors who can’t tell them anything new and often have a broader education and know less about bodybuilding than they do themselves (trust me I know, I’ve done the training myself). The problem is that many of these people also don’t take the trouble to inform themselves, for example, by simply addressing the biggest guy in the gym and asking questions (most of them actually enjoy explaining) or consulting sites like this one or other sources. So they walk into the gym and just do whatever. In many cases, you see ego-lifting as discussed above, but without them knowing that it should be different.
More Muscle Strength and Mass through Negative Training
Now we finally come to the point mentioned in the introduction. Studies have shown that eccentric training would yield more muscle strength and mass than conventional training focusing on the concentric portion.
How reliable are these studies and if they are reliable why isn’t it applied by everyone as the standard method of training? It is always important to know how a study was conducted. Under what conditions, what population (participants), measuring equipment, etc. There are many studies showing that eccentric training yielded more strength and muscle mass than concentric training. Most of these used untrained subjects. The difficulty with this is that the strength gain in untrained individuals after a period of training is often considerably greater than the growth in size would suggest. This is mainly due to the improvement of the neurological connection between the muscle and the brain.
In the article “The muscle strength of positive thinking,” I showed that simply thinking about training can make a muscle stronger by improving this neurological connection. In trained people, this effect is smaller because this connection is often already stronger. Research results among trained people will therefore be more attributable to actual changes in the muscle itself than to neurological effects. Therefore, there are studies that use trained individuals because this would be purer. Whether this is justified, I do not know. As mentioned above, most people train focusing on the concentric part. Especially in the case of most trained people, you can therefore expect a relatively larger response to eccentric training compared to concentric because even in the case of most trained people, the neurological connection when strictly eccentric training is not yet strongly developed.
For each study, I will indicate whether these were trained or untrained subjects, but also mention other relevant circumstances. The various studies sometimes have different outcomes to the same question, but in general, the following benefits of eccentric training have been demonstrated:
- During the eccentric phase, the muscle can generate more force
- Eccentric training leads to more hypertrophy than concentric training
- Eccentric training can lead to hypertrophy (muscle growth caused by training) in shorter training sessions than other training methods
- Eccentric training leads to greater (conscious) muscle damage, resulting in more recovery over a longer period
During eccentric training, the muscle can generate more force than during concentric training. [update 2/10/14] A soon-to-be-published study shows that eccentric training can develop 20% more strength [kelly 2014]. This is likely due, among other things, to the way the body activates different muscle fibers for different loads.
At low loads, you first use type I fibers. These are suitable for long-lasting, low load exercises. At the other end of the spectrum are type IIb fibers, which are suitable for heavy loads for a short time. A successful marathon runner has many type I muscle fibers, while a sprinter has many type IIb muscle fibers. In that respect, someone born as a dime in sports will never become a quarter.
When you train heavily, the type I fibers are used first. If they are insufficient, the type II fibers are also recruited, first IIA, then IIx, and finally the strong IIB fibers (this principle is called ordely recruitment). Keep this in mind and consider how much force you normally have to exert during “normal” concentric training. This is almost never 100% of your potential. Only in the last repetitions when you can no longer move the weight, do you use 100% of your strength, but then you are already training isometrically because the weight and thus the muscle no longer move. All repetitions before that work below your capacity.
When you train negatively, you immediately start (after warming up, see below) with a weight that you cannot lift concentrically. You immediately need your full strength to resist the weight for as long as possible, causing all types of muscle fibers to be activated. More intensity of the muscle due to more activity of multiple fibers is more (conscious) damage that needs to be repaired and leads to muscle growth [enoka 1997].
Over the past several decades, numerous studies have established that eccentric contractions can maximize the force exerted and the work performed by muscle…that they can attenuate the mechanical effects of impact forces; and that they enhance the [good] tissue damage associated with exercise.
R.M. Enoka, Cleveland Clinic Foundation
There are several studies that have demonstrated this. We start in Oslo where researchers from the University of Oslo divided 17 trained individuals into two groups of comparable strength (by first pairing individuals of comparable strength based on the initial test and then dividing the pairs into the two groups) [vikne 2006].
Eight participants did maximum concentric training and nine participants did eccentric training of the elbow flexors, the bicep curls. They measured the maximum eccentric and concentric strength, the speed at which the angle changes (forearm vs. upper arm. The cross-sectional area of the muscle at its largest point, and the cross-sectional area of individual cells were measured to determine the degree of hypertrophy. They had the participants train 2 to 3 times a week for 12 weeks. Measurements were repeated in week 15. In this case, eccentric training involved lowering the weight in 3 to 4 seconds.
Of all results, we are of course most interested in muscle growth. In the graph above, you can see in the top graph the growth of the muscles over the different parts of the upper arm expressed as the surface area of the cross-section in cm2. In the group that trained concentrically (CON), the size had only increased in one part of the muscle (especially distal, 1/8 and 2/8 of the muscle measured from the elbow). The increase in the average size of the entire muscle was not statistically significant (+0.7 ± 1.1 cm2, +3%). In the eccentric group (ECC), the muscle increased in length and the average increase was much larger (2.8 ± 1.4 cm2, 11%).
In conclusion, only eccentric training increased anatomical muscle and fiber cross-sectional areas in previously resistance-trained men. The results of this study suggest that it is important to create high muscular force in training to promote further hypertrophy in already well-trained human muscles.
H. Vikne, University of Oslo
Canadian researchers from the University of Saskatchewan came to the same conclusion in 2003 [Farthing 2003]. They had 26 untrained individuals aged 18 to 36 train one arm concentrically for 8 weeks and then the other arm eccentrically for 8 weeks. 10 other participants did not train as a control group. They also saw large differences in muscle mass increase between eccentric training and concentric training (results below).
…eccentric training was more effective than concentric training for increasing muscle hypertrophy
J.P. Farthing, University of Saskatchewan
Researchers at the University of Georgia also studied the effects of concentric and eccentric training in women. 16 women did concentric training, 19 did eccentric training, and 19 others served as a control group. In this study, they trained the quadriceps using leg extensions. In the group that trained concentrically, the average muscle size increased by 5%. In the group that trained eccentrically, this difference was 6.6%. Strength also increased more with eccentric training than with concentric training.
We conclude that Ecc is more effective than Con isokinetic training for developing strength in Ecc isokinetic muscle actions and that Con is more effective than Ecc isokinetic training for developing strength in Con isokinetic muscle actions. Gains in strength consequent to Con and Ecc training are highly dependent on the muscle action used for training and testing. Muscle hypertrophy and neural adaptations contribute to strength increases consequent to both Con and Ecc training.
E.J. Higbie, University of Georgia
Still not convinced? Researchers at East Carolina University also looked at the differences when they had 8 people train their quadriceps concentrically and 7 people eccentrically for 12 weeks. With eccentric training, strength (on eccentric repetitions) increased by 46%. Concentric strength increased (on concentric repetitions) by “only” 13%. When they looked at muscle stimulation/loading through EMG (electromyography) after 12 weeks, they found that muscle activity during exercises in the eccentric group had increased by 85% (!), while in the concentric group it was “only” 12%. Moreover, they observed that the increase in type II muscle fibers (which have more potential for growth) was 10 times greater in the eccentric group than in the concentric group.
It is concluded that adaptations to training with maximal eccentric contractions are specific to eccentric muscle actions that are associated with greater neural adaptation and muscle hypertrophy than concentric exercise.
T. Hortobágyi, East Carolina University
Swedish researchers came to the same conclusion. They also looked at the differences in effect on the quadriceps. Ten “moderately” trained men were divided into a group that trained eccentrically and a group that trained concentrically. They trained for 10 weeks, 3 times a week, 4 sets of 10 repetitions with the left leg followed by the same training for 10 weeks with the right leg (to also see the effect on the untrained leg). The greatest increase in strength they observed was in the test on strength at maximal eccentric force at 90 degrees. The greatest strength the leg could generate here increased by 35%. In the concentric group, this varied between 8% and 15%. However, they also noted the following:
In conclusion, effects of eccentric training on muscle strength appeared to be more mode and speed specific than corresponding concentric training
J.Y. Seger, Department of Neuroscience, Karolinska Institute
In other words, the speed at which the exercise was performed had more effect on the result in eccentric training than in concentric training. Assuming I have shown you enough studies now (there are more, see sources) demonstrating the effectiveness of eccentric training, I will now discuss its practical application. Based on the last mentioned study and other studies focusing on this, I will first address the question:
How fast should you perform negative repetitions?
What I did not mention above in the Canadian study is the fact that they, like the researchers from Sweden, also looked at the difference in fast and slow execution of the eccentric exercises. They looked at an execution both concentrically and eccentrically, in about 1 second for the fast execution and 3 to 6 seconds (concentric 3 seconds up and 3 seconds down) for the slow execution. They saw clear differences in results. As for the concentric exercise, this is not surprising. Conventional wisdom has taught us that the fast muscle fibers, type IIb and IIx, have more potential for muscle growth. By doing fast exercises with a lot of resistance, you activate these fibers more.
All fitness training still teaches that eccentric repetitions should be performed slowly. Probably because this is safer, especially for the attachments. Safer because many inexperienced people simply drop the weight. This leads to the second possible reason for as a teacher or instructor to have the negative part done slower in practice: To force people to resist during the negative part.
However, in terms of results, a fast execution in about 1 second is also more effective for eccentric repetitions. In the graphs next, you see the differences in results on muscle growth between eccentric and concentric and fast versus slow. ECC is the group that trained eccentrically, CON = concentric, and Control is the group that did not train. The three graphs represent the increase in the size of the biceps over various lengths of the muscle: Proximal is close to the shoulder, Mid Site is halfway, and Distal is close to the elbow.
We conclude that ECC fast training is the most effective for muscle hypertrophy and strength gain.
J.P. Farthing, University of Saskatchewan
American researchers at the University of Texas also came to the same conclusion when they measured the differences after execution at 30 degrees per second (about 3 seconds to lower in eccentric and 6 seconds in total for both directions in concentric training) and 180 degrees per second (about 1 second to lower in eccentric and 2 seconds in total for both directions in concentric training). 20 untrained people were divided into a fast (7 people) and a slow (6 people) group (the others formed the control group that did nothing). They also trained the biceps by means of eccentric training. They did this 3 times a week for 10 weeks, 4 sets of 6 repetitions.
The researchers did not look at muscle size, but the effect on strength and the ratio between type I and II muscle fibers. The latter with the knowledge that type II muscle fibers are better suited for muscle growth and maximum strength. In the eccentric group, muscle strength increased in all parts of a normal exercise (so eccentric, isometric, and concentric), the number of type I muscle fibers decreased, and the type II muscle fibers increased. None of this happened in the concentric training group.
After 10 weeks, the FAST group demonstrated significant [mean (SEM)] increases in eccentric [29.6 (6.4)%] and concentric torque [27.4 (7.3)%] at 3.14 rad x s(-1), isometric torque [21.3 (4.3)%] and eccentric torque [25.2 (7.2)%] at 0.52 rad x s(-1). The percentage of type I fibres in the FAST group decreased from [53.8 (6.6)% to 39.1 (4.4)%] while type IIb fibre percentage increased from [5.8 (1.9)% to 12.9 (3.3)%; P < 0.05]. In contrast, the SLOW group did not experience significant changes in muscle fibre type or muscle torque.
D. Paddon -Jones, Department of Surgery, University of Texas
Lower quickly, but controlled!
This means that you should lower the weight quickly. The emphasis here is on lowering. So, it is not intended that you simply drop the weight. Not only to prevent injuries, but also because otherwise, you will completely miss the effect of the training. Therefore, choose a weight that is so heavy that with full resistance, the eccentric part lasts no more than 1 second. If you have never trained negatively before, it is advisable to start by performing the movement in 3 to 4 seconds to learn control. This can also be done as a warm-up.
Negative training in practice
As part of the usual training
Eccentric training can be done in several ways. The first one I have already described. Namely, as part of your usual training by focusing on the eccentric part instead of neglecting it due to poor technique. However, if you do not train based on eccentric training and thus your weight is lighter, you should not assume the fast execution in one second. This only makes sense when your weight is based on eccentric training and therefore heavier. When you take a weight for “normal,” concentric training, this is actually too light for the negative part. One method to force yourself to train the eccentric part well is by doing this part in 3-4 seconds.
Back to bench press: You push the bar out explosively in 1 to 2 seconds, then hold it tense for the same amount of time (the isometric part), and then lower the bar in 3-4 seconds (and then hold it tense for 1 second again before pushing out again). You will notice that you need to take lighter weights than usual or do fewer repetitions. An additional advantage of this is that the risk of injuries decreases because you need less weight or repetitions (every time the muscle attachment needs to pull on the bone) for the same intensity. For clarity, by performing slowly in 3-4 seconds instead of 1 second, you will not achieve the optimal effect of eccentric training. However, you ensure that you at least benefit from the eccentric part instead of not at all.
As a specific training method, with spotter
The other method is what is usually meant in practice by “negative repetitions.” This is best done with a partner (a so-called “spotter”), although there are plenty of ways to do this alone if you’re a bit creative. With this method, the idea is to take a weight that is actually too heavy. This may sound contradictory after my explanation about ego-lifting, but I’ll explain it. Take the example of bench pressing again. So, you take weight that you can’t quite push out yourself. In this exercise, it’s not about pushing out. You have a partner help with the pushing out, but then lower the weight yourself in 1 second. It’s important here that it offers you as much resistance as possible to bring the weight down/back in 1 second. If you can’t do it and it’s too fast, then you need to take a lighter weight. If you have time and/or energy left, then you take a heavier weight for the next set. IMPORTANT! Make sure you have a good partner who understands what is intended. Because the weight is relatively very heavy, you’re screwed if your spotter isn’t paying attention at the bottom of the movement.
As a specific training method, alone
Although training with a partner may be stimulating for some people, I personally prefer to train without a fixed training partner because I find it difficult enough to coordinate when I’m going to train at home, let alone having to consider someone else. In addition, I only want to have to consider myself regarding my schedule and its execution. Moreover, you can always ask for help in the gym when you really need it. Normally, however, you only need this help for the heaviest sets in the case of risky exercises such as bench pressing with a free bar or squatting, and in some cases when you want to do forced repetitions (continuing when you actually can’t anymore).
With negative repetitions, it’s more difficult when you’re alone because then you would always need help and you don’t want to constantly bother someone. What you can do in this case is choose exercises where you can do the concentric part with two arms or legs and the eccentric part with one arm or leg.
For example, the leg press or leg extensions. Take a weight that you can push up with two legs, but not with one. Push the weight up with two legs and let it down with one leg. Again, if it doesn’t work and it’s too fast, then you need to take a lighter weight. If you have time and/or energy left, then you take a heavier weight for the next set. If you understand this principle, you can apply it to many exercises. You can do bench pressing and shoulder pressing in a Smith machine this way. Biceps curls and tricep pulldowns can be done by letting one hand help with the concentric part and doing the eccentric part with one hand. For the back, it’s the same, pulling down with two arms and letting it go up with one arm (wide grip only with machine/device for balance).
Always do a good warm-up!!
More important than with concentric training is a good warm-up. You generate much more power with eccentric training because the weight is always actually too heavy. Where you stop with concentric training because you can’t do it anymore, eccentric training begins. Make sure you are well warmed up both by cardio and a muscle-specific warm-up. That means first “just” concentrically building up in weight.
Negative training as part of your training schedule
Okay, you now know why it’s useful to train eccentrically and how this can be done in practice. The only question remaining is how to incorporate this into your fitness schedule. I’m not saying you should only train eccentrically from now on. Just as there is no “best exercise” for certain muscle groups because your body gets used to every stimulus and responds less and less to it, it also makes little sense to train only negatively.
You should also consider to what extent you can always train at this intensive level without getting injured. In many of the mentioned studies, they ended up with fewer participants than they started because some dropped out with complaints of pain. This is not uncommon. They often trained the same muscle group 3 times a week at high intensity. The most seasoned bodybuilders will usually train a muscle group at most twice a week, with the exception perhaps of the abs. HIT, High Intensity Training (low volume high intensity), has also been shown more often to lead to more muscle mass and many bodybuilders train according to this method. However, in this case as well, you see that they have to do a lot of warm-up sets before they can start with the HIT training, making it look like a normal training again when you look at the number of sets performed in HIT or normally.
Moreover, you also see relatively many bodybuilders among the followers of HIT who had to end their careers due to nasty injuries (for example, Dorian Yates). However, it is good to make eccentric training a much more important part of your training than you probably do now. You can choose, for example, to perform at least one exercise eccentrically per muscle group in every training session. Another option is to train negatively only for a few weeks and then concentrically for a few weeks. You can also choose to make negative repetitions when you can’t make concentric repetitions anymore and thus do forced repetitions. This can only be done with a partner or in exercises that you can also train eccentrically alone. For example, if you do bicep curls with one arm, you do your repetitions until you can’t anymore and then you let the other arm help with the concentric part and focus on the eccentric part.
Conclusion negative training
Eccentric training has been shown in multiple studies to result in greater gains in strength and muscle growth than concentric training. The speed of execution is important, and the execution of the eccentric part in 1 second at maximum load has been shown to be optimal. You can apply it in various ways in your training, with a good warm-up being important. To get used to providing sufficient resistance during the eccentric part, it is advisable to start with this part in 3 seconds and gradually decrease to 1 second. Keep in mind that it is very intensive, so you may need to adjust your recovery accordingly.
References
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Comparison of Concentric and Eccentric Bench Press Repetitions to Failure.Published Ahead-of-Print Journal of Strength & Conditioning Research:Post Acceptance: September 29, 2014 doi: 10.1519/JSC.0000000000000713
