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In a message dated 97-10-26 13:46:23 EST, you write:
<< Can anyone tell me why eccentric exercise is so beneficial? I understand that internal muscular friction aids eccentric and hinders concentric lifting performance. In this respect however the actual force being applied by the muscle itself could be identical. Are eccentrics good only in that they prolong the stimulus to create a deeper inroad? If this is the only benifet wouldn't continued exertion being applied after concentric failure prove to be just as effective if the static was of the same duration? >>
I'll try to address this without being my usually ridiculously overly wordy self: There are two major factors to be considered here, one is positive, the other is negative. The positive factor is intensity, the higher the intensity of any particular stress, the greater the degree to which the body will be stimulated to produce an adaptation to it. The amount of exercise is negative. The more you do, the deeper an inroad you make into your body's existing supply of adaptive resources. Of course, you want to increase the positive factor (training intensity) and decrease the negative factor (training volume, or the amount of work performed) as much as possible. Negative training allows one to train at a maximal level of intensity, while performing less overall work, which is due in part to the effects of intramuscular friction. Arthur wrote a long article on this explaining the math involved, and as soon as I can find it, I'll post it for everyone.
Part of finding the right answers is asking the right questions. I commend Teri for raising some excellent ones.
Andrew M. Baye
In a message dated 97-10-26 13:46:23 EST, you write:
<< Well what do you suggest I should do? I'm only 18 and everyone's saying how they wish they had my recovering abilities, but just lately, I've begun to stay sore for up to 6 or 7 days after each workout, no matter what the body part. If I don't train during that time, then I only get in the gym once a week!! That's not enough!! Any suggestions? >>
Soreness is subjective, and not an indication of anything except the fact that you are sore. The only way to know if you are allowing your body adequate time for full recovery and adaptation between workouts is to keep accurate records of your progress with which to evaluate this by.
How do you know that once a week is not enough? Unless you are keeping a progress chart, and have tried this, there is no way to tell. Since tolerance to intense physical stress and the ability to recover from and adapt to it varies tremendously from individual to individual, each individual must isolate and experiment with these variables to determine the optimal training volume and frequency for themselves, and this may very well be much lower than we suspect.
I personally know several people who have made excellent gains using the SuperSlow HIT protocol, who perform only 4 to 6 exercises, and train only once per week. One such individual has gained 30 lbs. over the past 3 years, another, over 50, on this same frequency of training. I start out all my clients at twice a week, and reduce this to once every 5 or 6 days, and eventually once per week, and they continue to progress at a dramatic pace.
In a recent phone conversation with Arthur Jones, he remarked that Dan Carpenter, M.D. a researcher for MedX at the University of Florida, LOSES strength if he trains once per week or more. He makes little or no progress if he trains more frequently than twice per week. If he trains only once every third week or less, he makes significant progress. Some people have extremely poor recovery ability, and in such cases, not only is such extremely infrequent training effective, it is the only way they are able to make any progress. I have also discussed this with Doug McGuff, M.D., who is currently working on an article on determining proper "dose-response" curves for training, and has also suspected the same thing.
Upon returning from vacations of a month or more, many clients are able to pick up right where they left off, and are often even slightly stronger. I have one client, who, due to scheduling difficulties, has only trained once every other week for the past 3 months. She has increased in weight in almost every exercise, almost every single time, and has never failed to at least increase her reps.
Based on these observations, it would appear that we need much less training than many people believe, and that decompensation does not begin anywhere near as quickly as was once thought. The average person who does not strength train only loses half a pound of muscle per year after the mid 20's, so I hardly think that a person who is strength training would lose a significant amount of muscle after only a week or two off. In many cases, this may even dramatically improve one's progress.
My advice to you is this: Keep accurate records of your workouts with which to evaluate your progress. If you are not making satisfactory progress: train harder, train less, and allow your body more time for recovery and response between workouts.
Andrew M. Baye
> From: T.Pokere@mailbox.uq.edu.au
> > Can anyone tell me why eccentric exercise is so beneficial? I
The eccentric action provides numerous benefits to an athlete. Despite the size principle of orderly recruitment of motor units, it has been found that during eccentric actions, fast twitch motor units sometimes fire before slow twitch ones (1). This is an important implication for strength athletes and bodybuilders since fast twitch fibers create more force and have more potential for hypertrophy than slow twitch fibers.
Also, fewer motor units are activated during an eccentric action, which creates a higher load upon activated muscle fibers (1). This creates greater muscle damage which is a factor in muscle hypertrophy.
Also, when concentric-only training is compared to eccentric-only training, eccentric-only training produces greater muscle hypertrophy (2).
Both types of actions have tremendous benefits to any athlete, and are both necessary for optimal strength development and muscle hypertrophy. It is important not to ignore either.
1. Behm, D.G. Neuromuscular implications and applications of resistance training. J. Strength and Cond. Res. 9(4):264-274. 1995.
2. Higbie, E.J., K. J. Cureton, G.L. Warren III, and B.M. Prior. Effects of concentric and eccentric training on muscle strength, cross-sectional area, and neural activation. J. Appl. Physiol. 81(5):2173-2181. 1996.
>Can anyone tell me why eccentric exercise is so beneficial? I understand that internal muscular friction aids eccentric and hinders concentric lifting performance. In this respect however the actual force being applied by the muscle itself could be identical. Are eccentrics good only in that they prolong the stimulus to create a >eeper inroad? If this is the only benifet wouldn't continued exertion being applied after concentric failure prove to be just as effective if the static was of the same duration?
Empirically, if you compare athletes who do only concentric work (Olympic lifters) to those who do eccentric work (bodybuilders), the latter has MUCH more muscular development than the former. And, study after study after study has shown that the combination of concentric + eccentric contractions spurs more muscle growth than concentric only (see below).
The following is an excerpt from a book (yes, *that* book for anyone on this list who knows me) I'm working on currently (it is a bit disjointed because I didn't want to waste ANY MORE bandwidth with the entire section on What Makes Muscle Grow). It may not be used ANYWHERE except this list without my permission. Blah, blah, blah.
***** 3. An eccentric (lowering) component to training: Numerous studies have have compared concentric only training (lifting the weight only) to eccentric training. The great majority of them find that the eccentric training groups experiences more growth even when the total number of repetitions (time under tension) performed by both groups is identical (2,49,50,51,52,53) .
Some of the major differences between concentric and eccentric muscle actions appear below:
a. Force capacity during an eccentric muscle action is approximately 30-40% greater than that during a concentric muscle action (8,9). That is, you can lower 30-40% more weight than you can lift concentrically. b. Type II muscle fibers (which show the greatest amount of growth) are preferentially recruited during eccentric actions (8,9). As Type II fibers have a greater force production capacity than Type I, this may partly explain the 30% greater strength seen during eccentric training.
**Note (this is not in the book): The intramuscular friction hypothesis is just that and, to my knowledge, has not been tested experimentally. Ultimately, it matters little to me what the cause of the differential between positive and negative strength is, the fact is that it exists whether it's friction, fiber recruitment differences or gremlins pulling on the muscle fibers.**
c. During eccentric muscle actions, less muscle fibers are recruited (8,9). This means that the fibers recruited receive more overload per fiber (56) which may explain the preferential growth seen.
**Note (also not in the book but it needs to be): this also explains why eccentrics do more damage to muscle fibers than concentric. The fibesr working are working harder and the likelihood of damage is much higher.
d. Eccentric but not concentric lifting stimulates protein synthesis (9)
References (in case anyone is impressed by such things) 2. Hortobagyi, T. et. al. "Greater initial adaptations to submaximal muscle lengthening than maximal shortening." J Appl Physiol (1996) 81: 1677-1682. 8. "Neuromechanical basis of kinesiology" Roger M. Enoka. Human Kinetics Publishers1994. 9. "Skeletal muscle: Form and Function" Alan J. McComas. Human Kinetics Publishers 1996. 49. Hortobagyi, T. et. al. "Adaptive responses to muscle lengthening and shortening in humans" J Apply Physiol (1996) 80: 765-772. 50. Colliander E.B. and P.A. Tesch "Effects of detraining following short term resistance training on eccentric and concentric muscle strength" Acta Physiol Scand (1992) 144: 23-29. 51. Dudley, G.a. et. al. "Influence of eccentric actions on the metabolic cost of resistance exercise" Avaiat Space Environ Med (1991) 62: 678-682. 52. Hather B.M. et. al. "Influcence of eccentric contractions on skeletal muscle adaptations to resistance training" Acta Physiol Scand (1991) 143: 177-185. 53. Armstrong, R.B. "Mechanisms of exercise-induced muscle fibre injury" Sports Med (1991) 12: 184-207. 56. Brenda N. Teague and James A Schwane "Effect of intermittent eccentric contractions on symptoms of muscle microinjury" Med Sci Sports Exerc (1995) 27: 1378-1384.
****
Static contractions are not as effective (other than allowing one to fatigue more muscle fibers after concentric failure has been reached) for growth because the mechanics of cross-bridge interactions are different than with concentric and eccentric contractions. I'm not exactly sure what the differences are but studies also show that isometric work BY ITSELF does not reliably increase growth.
One current theory of muscle damage/growth is: All of the above information (tension, metabolic work, and eccentric induced damage) has led Friden et. al. (61) to propose the following schema for muscle damage and remodeling (i.e. growth). 1. Depending on the force requirements, a given number of muscle fibers will be recruited. 2. The recruited muscle fibers fatigue from performing metabolic work. 3. Upon reaching fatigue, individual fibers reach a point, termed ischemic rigor, where they physically 'lock up' due to insufficient ATP. This 'locking up' occurs during the concentric part of the movement 4. The subsequent eccentric muscle action causes small tears to occur in the muscle, stimulating remodeling and growth. *Please note that this proposed schema still requires further research to be validated.* It has also been suggested that tears to the cell membrane allow calcium to flow into the cell, activating enzymes which break down protein (61,62). Full recovery from this type of eccentric trauma is completed with 4-7 days suggesting that the same muscle should not be worked any more frequently than that, at least not with heavy eccentric contractions.
60. Priscilla Clarkson and I. Tremblay "Exercise-induced muscle damage, repair, and adaptation in humans." J Appl Physiol (1988) 65: 1-6. 61. Friden, J. and R.L. Lieber "Structural and mechanical basis of exercise-induced muscle injury" Med Sci Sports Exerc (1992) 24: 521-530.
Copyright 1997. Lyle McDonald
A static contraction FOLLOWED by an eccentric would most likely achieve the conditions outlined by Frieden et. al. During the static, muscle fibers will be recruited (based on load) and fatigue (since they are doing metabolic work). The subsequent eccentric would damage those muscle fibers which had been fatigued.
Wait a second, isn't this the Sportsci list?
Lyle McDonald, CSCS "Just remember: we all come into life the same way: terrified, screaming and covered with blood......And it doesn't have to end there if you know how to live." Some comedian
I suspect that your soreness for such a long timeafter your workouts is something you will work through over time. In the meantime you might just discover that onceaweek per body part is PLENTY. Also, and I'm not sure of the science here, you might try lowering your weights and increasing your reps to encourage vascularization of the muscle nd thereby speed removal of lctic acid and other byproducts of metabolism that contribute to your soreness as well as increase delivery of O2 and nutrient to the recovering tissue. Ken