From: cyberpump@geocities.com
Date: Sun, 19 Oct 1997
Subject: HIT Digest #17
To: HIT.Digest@geocities.com
Reply-To: <cyberpump@geocities.com>

This list digest contains the following message subjects:

  1. Re: Smith Machine and Aerobics
  2. Re: HIT Digest #16
  3. Re: HIT Digest #16
  4. Re: HIT Digest #16
  5. Re: HIT Digest #16


<MSG1>
Date: Sat, 18 Oct 1997
From: bcollins@hotmail.com
Subject: Re: Smith Machine and Aerobics

> >2) I have been doing powerlifting routines and decided to eliminate aerobics (as recommended by F. Hatfield). However, I seem to have gained some fat and I feel less fit. I would like to hear some opinions on: should a trainee going for strength gains do aerobics? If so then what kind and how much. >

I think it depends on your goals as far as eliminating aerobics. If you are serious about competing and or really increasing your powerlifts to their max potential, then cut the aerobics. If not, then keep doing them. If you have increased your fat, reduce your calories a bit to compensate for the decrease in activity. I have found that ANY aerobic work cuts into max strength to some degree. You have to determine the trade-offs versus your goals. Is an extra 20lbs on your squat worth the feeling of not being fit?

Brad

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<MSG2>
Date: Sat, 18 Oct 1997
From: DrewBaye@aol.com
Subject: Re: HIT Digest #16

In a message dated 97-10-18 06:29:18 EDT, you write:

<< I've got a book by Little and Sisco where they recommend the use of a power factor equation to optimise the stimulus i.e. Power = Total weight / total time. This in my opinion is good in that it is emphasising the "optimal" anaerobic stimulus. My question is does anybody know how this customised type of equation could be applied to static contractions. Metabolic work seems to be a "little" more difficult to determine. >>

The Power = Total Weight/Total time equation is incorrect. Mechanical definitions of work and power do not apply to metabolic work, and even if they did, this equation does not account for the effects of acceleration, momentum, etc.

The following article by Arthur Jones might put this in better perspective:

[Moderator's note: If possible, try to refrain from posting full articles. I was guility myself and Rob nailed me. :)]

Metabolic Cost of Negative Work

by Arthur Jones

(written July, 1975, published in the Athletic Journal, January 1976 issue)

[comments in brackets are mine - A.B.]

A review of the literature on negative work may lead to more confusion than knowledge, primarily because everything written on the subject seems to be guilty of at least four faulty assumptions.

ONE... it has been assumed that human muscles are stronger during negative work, by comparison to their strength during positive work.

TWO... it has been assumed that the metabolic cost of negative work is much lower than the metabolic cost of positive work.

THREE... it has been assumed that negative work has very little effect on the cardiovascular system.

FOUR... it has been assumed that the ratio of positive metabolic cost to negative metabolic cost changes as the rate of work changes.

Any or all of these four basic assumptions may be true, but they have not been proven. They have been generally accepted, I think, only because they appear to be true on the basis of rather casual observation. But even if they are true, the degree of truth involved is far less than that which has been generally accepted.

All of these four basic assumptions are based upon apparent differences between negative and positive work. However, when several factors that have previously been ignored are considered, it is immediately obvious that the real differences, if any, are far less than the apparent differences.

ONE, a difference in strength. While it is certainly true that an exerciser can lower more weight than he can lift, it does not necessarily follow that his muscles are actually stronger during negative work than they are during positive work.

The muscles may be stronger; but even if so, they are not as much stronger as they appear to be. The apparent gross difference in strength is, I think, primarily a result of friction... internal muscular friction.

While lifting a weight, the muscles must contract with sufficient force to move the imposed resistance... but they also have to overcome their own internal friction. Thus, during positive work, friction is working against the muscles.

Whereas, during negative work, friction is working for the muscles instead of against them.

Therefore, an exerciser's usable strength during positive work is equal to the force provided by his muscles, minus friction... and his usable strength during negative work is equal to the force provided by his muscles, plus friction. Friction hurts him during positive work and helps him during negative work.

It may well be that all of the difference in usable strength cannot be accounted for by friction; but even if not, it still remains true that at least part of the difference is a result of friction... thus the actual difference is certainly less than the apparent difference.

At the moment [1975] we are conducting careful tests in an effort to determine exactly what part friction plays in the matter.

TWO, a difference in metabolic cost. A great deal of confusion exists on this point because of attempts to compare metabolic work with mechanical work, and secondly, because of a failure to consider several related factors.

By definition, work requires movement... no movement means no work; and while this is undoubtedly true in regard to mechanical work, it certainly is not true in relation to metabolic work.

Muscles produce force, and it is easily possible for a muscle to produce a high level of force without producing movement; logically, it appears that the metabolic cost of muscular force production would be related to the level of force produced and the time that the force is maintained... rather than the amount of mechanical work performed.

If, for example, a 100-pound barbell is held motionless at the halfway position of a curling exercise, then the muscles will be required to produce a certain level of force to prevent the downward movement of the barbell. Providing that force will certainly entail metabolic work... yet no mechanical work is involved.

Slowly curling a 100-pound barbell also requires a greater metabolic cost than curling the same barbell at a more rapid pace; even though the amount of mechanical work involved is exactly the same in both cases.

Many other examples could be given to illustrate the same point, but it should now be obvious that attempts to relate metabolic cost to mechanical work are doomed to failure... there is no meaningful relationship. We must have another standard for comparison.

The only meaningful standard I can think of is force-time... the amount of force produced by the muscles multiplied by the time that the force is maintained.

But again, attempts to measure force-time will be meaningless if we fail to consider friction... and will be very difficult in situations involving movement.

At the moment [1975] we are working on the development of a practical means to accurately measure force-time in situations involving movement... but until and unless such equipment is produced, force-time can probably be measured accurately only in static situations.

It should be reasonably simple to determine force-time in static situations... and if this is done accurately, I think it will then be shown that a very close relationship exists between force-time and metabolic cost. Perhaps an exact relationship will be established... and if so, then we will have a standard for comparison. But in the meantime, no such standard exists; attempts to use mechanical work as a standard for determining metabolic cost have led to widespread confusion.

When and if it becomes possible to compare the metabolic cost of negative work with that of positive work on the basis of a meaningful standard, it may well be shown that the metabolic cost is in fact exactly the same in both cases; but even if not, it will certainly be shown that the difference, if any, is far less than it is now generally assumed to be.

THREE, a difference in cardiovascular effects. When it becomes possible to accurately determine the difference, if any, between the metabolic cost of positive work and that of negative work... then, and only then, will it also be possible to make meaningful comparisons between the cardiovascular effects of positive work and those of negative work. In the meantime, any attempt to make a meaningful comparison is limited by lack of a standard for comparison.

FOUR, changing ratios of metabolic cost as a result of changes in rate of work. It is generally believed that a faster rate of work produces a higher ratio of metabolic cost and vice versa.

If, for example, two subjects are seated in the same leg-press machine, in such a manner that one subject performs all of the positive work, the lifting part of the exercise, while the other subject performs all of the negative work, the lowering part of the exercise... then, at a slow rate of work, the man performing the positive work might be required to pay a metabolic cost that is twice as high as the metabolic cost required of the man performing the negative work.

But it does not follow that the actual metabolic cost is different to that degree... or even that there is any difference at all. Because the force-time factor is different... even though the speed of movement may be exactly the same with both subjects.

Remember, the man doing the positive work is lifting the resistance while also working against friction... and the man doing the negative work is lowering the resistance while being helped by friction. Thus it could easily be possible that the man performing the positive part of the work was actually producing twice as much force as the other man.

But, in any case, it is obvious that the muscular work (as opposed to mechanical work) is certainly not equal... so it is only natural that the metabolic cost would also be different.

Then, if the rate of work is increased, the apparent ratio between the metabolic cost of positive work and negative work will also be changed. If, for example, the rate of work is doubled, then the apparent ratio may change from a ratio of two-to-one to a ratio of three-to-one. And again, I think that any such apparent change in ratio is an illusion resulting from a failure to consider all of the involved factors.

If, for example, the rate of work is increased by increasing the speed of movement, then a point is eventually reached where the amount of negative work involved becomes literally zero. This occurs when the downward movement of the weight is occurring at a speed equal to the normal acceleration produced by gravity; in effect, when the weight is simply dropped.

In such a situation one man would be lifting the weight fairly rapidly... while the other man would be simply dropping it, making no attempt to stop or delay the normal acceleration resulting from gravity. Obviously then, the man doing the positive part of the work would be working... while the other man would be doing literally nothing.

Even more confusion on this point has resulted from failure to consider basic metabolic requirements [basal metabolism]. A man at rest is constantly paying a certain metabolic cost merely to stay alive... thus, in order to determine the actual metabolic cost of any particular activity, we must first subtract the basic metabolic cost from the total metabolic cost, any resulting difference then being the metabolic cost of that activity. [Calories burned per unit of time during various activities are often grossly overestimated as a result of failure to consider these points.]

If, for example, an individual's basic metabolic cost while resting was 100 units per minute... and if his total metabolic cost increased to 150 units per minute while walking slowly on level ground... then the metabolic cost of walking at that pace under those conditions was 50 units per minute.

Unfortunately, when attempts have been made to determine the metabolic cost of positive work as compared to the metabolic cost of negative work, it appears that the basic metabolic cost was not subtracted from the totals. Instead, for a meaningful comparison, the net metabolic costs should have been compared.

I do not know just what the exact results of careful tests on this subject will be... but it appears that many of the tests conducted in the past left a great deal to be desired, and that the conclusions based on these tests are in error.

People who are interested in meaningful areas of research in the broad field of exercise physiology might find it very fruitful to conduct careful tests in connection with the points raised in this article; in the meantime, we are conducting our own tests... which will be published in due coarse.


<MSG3>
Date: Sat, 18 Oct 1997
From: DrewBaye@aol.com
Subject: Re: HIT Digest #16

In a message dated 97-10-18 06:29:18 EDT, you write:

<< I have been doing powerlifting routines and decided to eliminate aerobics (as recommended by F. Hatfield). However, I seem to have gained some fat and I feel less fit. I would like to hear some opinions on: should a trainee going for strength gains do aerobics? If so then what kind and how much. >>

No! Aerobics contributes nothing of value to an exercise program, and only wastes valuable biological resources that the body could otherwise have used for recovery and growth. If you want to decrease your bodyfat, then simply cut your calories back somewhat. I went from about 8% bodyfat to under 3% in under 6 weeks doing nothing but HIT (working out once a week) and a moderately reduced calorie diet.

I recommend recording your daily intake for a week, as well as your weight. If your weight doesn't change, than your average daily caloric intake is roughly equal to your daily caloric expenditure. Subtract 500 from this number, and that's the daily caloric intake you have to follow to lose bodyfat at a rate of one pound per week. This, is of course, a rough estimate, but it works rather well. Don't bother with the aerobics, it doesn't burn that many calories, and will interfere with the production of strength increases stimulated by REAL exercise, high intensity strength training.

Andrew M. Baye


<MSG4>
Date: Sat, 18 Oct 1997
From: TFMonroe@aol.com
Subject: Re: HIT Digest #16

In a message dated 97-10-18 06:20:43 EDT, zoharyz wrote:

<< 2) I have been doing powerlifting routines and decided to eliminate aerobics (as recommended by F. Hatfield). However, I seem to have gained some fat and I feel less fit. I would like to hear some opinions on: should a trainee going for strength gains do aerobics? If so then what kind and how much. >>

I have the same problem in that unless I do aerobics I gain fat. I am presently doing 1/2 hour of aerobics I.E. stationary bike, treadmill, stair stepper four days per week. I lift two days per week and have increased my bench press by 17% over the past few months. In my case, aerobics are a must and I still have a weight and fat problem.

Tom Monroe


<MSG5>
Date: Sat, 18 Oct 1997
From: lylemcd@onr.com
Subject: Re: HIT Digest #16
>Date: Thu, 16 Oct 1997 21:22:06 +1000
>To: cyberpump@geocities.com
>From: T.Pokere@mailbox.uq.edu.au
>Subject: Static contraction recomendations

> > >I've got a book by Little and Sisco where they recommend the use of a power factor equation to optimise the stimulus i.e. Power = Total weight / total time. This in my opinion is good in that it is emphasising the "optimal" anaerobic stimulus. My question is does anybody know how this customised type of equation could be applied to static contractions. Metabolic work seems to be a "little" more difficult to determine.

This is where Sisco and Little messed up. They basically equate mechanical work (a simple equation based on load on the bar, distance moved and the time it takes) and metabolic work. While I give them 10 points for trying to quantify the optimal training stimulus, they lose about a billion for making this simple mistake.

For example, according to their powerfactor equations, an individual who benches 150 lbs for 10 reps in 60 seconds has a lower powerfactor than an individual who benches 150X10 in 30 seconds. They argue that the higher power means more muscular overload. Sorry, no dice. The use of momentum in the second individual means LESS muscular overload not more because there is less tension on the muscles.

And, as you say, their equations cannot possible apply to isometrics. I guess you have the lowest powerfactor of all doing static contractions since you are not moving the bar at all (no mechanical work = no power = no powerfactor number). Like I said, Sisco and Little need to seriously rethink their equations and premise. The body isn't a simple engineering problem.

>Date: Sat, 18 Oct 1997 08:38:08 +0200
>To: <cyberpump@geocities.com>
>From: zoharyz@netvision.net.il
>Subject: Smith Squats and aerobics

> > >1) I have been regularly doing Smith squats in my routine with good results. The use of the Smith machine enables me to work safely, using good form and without a spotter. I stress good, deep technique. However, I know that some guys oppose Smith squats. Can anybody tell me why ? I would like to hear any opinions on Smith squats.

Let's see 1. It's a totally non-functional movement for one. I like to train my clients to have functional strength, not just isolated gym strength. 2. The smith machine takes the low back out of the equations during squats. Which means that as soon as you go to pick something off the floor (which is a squat at it's most basic), you risk lowback injury because you haven't strengthened it in a functional patter. 3. The smith machine takes the hamstrings out of the equations (allowing for more knee strain due to impaired co-contraction of quads/hams) 4. The smith machine imposes a linear movement onto a non-linear creature (humans). See #1.

If you want to squat without a spotter, get thee into a power rack and set the safety pins just below your bottom position. IF you get stuck, you just squat a bit further and dump the bar. I've been squatting without a spotter for years in a power rack with no injuries.

>2) I have been doing powerlifting routines and decided to eliminate aerobics (as recommended by F. Hatfield). However, I seem to have gained some fat and I feel less fit. I would like to hear some opinions on: should a trainee going for strength gains do aerobics? If so then what kind and how much.

Too much cardio (and at too high an intensity) will definitely impair strength and mass gains. However, a little may improve them. Lemme explain: recovery between sets (and to a lesser degree between workouts) is mediated by aerobic factors. After a gut busting set of squats, you're breathing like a freight train. Why? Oxygen debt which is repaid by aerobic energy systems. A little aerobic conditioning may help you to recover between sets (if you do multiple). Between workouts: the increased capillary density and blood flow to the muscles *might* improve nutrient influx to the muscles.

As to guidelines, I recommend the following: 1. No more than 3 days per week (the minimum to get benefits) 2. 20-30' maximum 3. Low intensity (below 70% of maximum heart rate). Too high an intensity of aerobics (close to somethign called the lactate threshold which I really don't want to get into because I've had to define it on 2 other lists this week) will recruit Type II muscle fibers, telling them to become 'more aerobic'. And they will shrink 4. Non-impact, especially if you're carrying a lot of muscle mass. Running and high impact aerobics are a no-no for the knees for most bodybuilders. So, cycling, walking on treadmill, swimming, maybe stairclimber if you can keep heart rate down.

Lyle McDonald, CSCS "If you're not part of the solution, you're part of the precipitate." Anon

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