QUESTION: You do not subscribe to the notion that exercise, in itself, is “healthy” for people. We covered this in some detail in Body By Science, but I would like to have you elaborate on this for the benefit of the readers on our web site.
MCGUFF: Well it depends on how you define exercise. If you just define it as “physical activity in general,” then, no. Physical activity in general has huge wear and tear issues associated with it. If you look at your average hunter-gatherer or average human up until the beginning of the twentieth century, average life expectancy was in the 40s. And most people by the time they reached age 40 had debilitating, crippling, osteoarthritis because of overuse injury. So exercise in and of itself is not necessarily a healthy thing and it can have, over a span of time, extraordinarily negative health consequences. So, no, exercise just by itself is not necessarily a healthy thing.
QUESTION: And your belief is that it’s the functional ability that exercise – particularly strength training — enhances that is where the dividends of exercise lie.
MCGUFF: Correct. I mean true health, if you really look at it is just the absence of disease. The concept of “super health,” meaning health above and beyond a non-diseased state, is really kind of silly. What most people take as super health is really health with enhanced functional ability, and that’s what proper strength training exercise affords for you. Your ability to function better and more efficiently as a result of increased strength and physical capacity, but that doesn’t necessarily improve your health off of its baseline in absence of disease.
QUESTION: That is an excellent point. In Body By Science we introduce your concept of “Global Metabolic Conditioning” and how properly performed strength training is actually the best cardiovascular exercise one can do. This obviously goes against the grain of how most people in the fitness industry have come to understand cardiovascular fitness. How is high intensity strength training, usually described as “anaerobic” training, optimal for producing cardiovascular improvements, which are usually described as “aerobic?”
MCGUFF: Well that is a complex question, not because the answer is complex but because contemporary exercise physiology has so muddied the water that it’s difficult to even talk to people about the subject. They talk about “aerobic” versus “anaerobic” but if you look at human metabolism — just take a cell in the human body. The cell is filled with fluid called Cytosol. Inside the cell you have little organelles called mitochondria. Energy enters into the cell in the form of glucose and it is metabolized in the liquid portion of the cell anaerobically from glucose through a series of about 20 chemical reactions to a chemical called Pyruvate. That is anaerobic metabolism. Pyruvate then gets moved inside the mitochondria where it is metabolized through a complex process to a total of 36 ATP molecules. That is called “aerobic” metabolism. Now “Aerobics” as a form of exercise is a low intensity form of exercise that allows the mitochondria to do its work at the pace that its capable of doing it, so that portion of metabolism is kind of isolated out. And over time all sorts of positive health benefits were associated with this specific metabolic adaptation. So it became a foregone conclusion that aerobic conditioning was cardiovascular conditioning and the two were interchangeable. What we forgot is the heart and blood vessels support the entire functioning of the cell – not just the mitochondria – but every component of metabolism is supported by the cardiovascular system. And strength training is actually the best way to train the cardiovascular system because it involves all components of metabolism — the metabolism that goes on out in the Cytosol, in the liquid portion of the cell, and the absence of oxygen AND the metabolism that occurs in the mitochondria. So, by involving all of metabolism, the heart and blood vessels have to support all of those metabolic functions, not just the aerobic function. So it’s a better biochemical stimulus. If you look in a biochemistry textbook, you’ll notice that when glucose is metabolized to pyruvate – the glycolysis cycle – the glycolysis cycle can actually turn much faster than the Krebs Cycle in the mitochondria. So what ends up happening is you end up producing pyruvate at a rate faster than the mitochondria can use it in the presence of oxygen. That pyruvate gets converted to lactate or lactic acid and that’s what produces the “lactic acid burn” that occurs with anaerobic exercise. But only by pushing anaerobic exercise as fast as you can will you be producing pyruvate at a rate that causes the aerobic cycle to cycle as quickly as possible. If you do sub-maximal training you’re not pushing your aerobic cycle as much as it can be pushed. And when you recover from a high intensity set of exercise and that lactate is stacked up, it gets converted back to pyruvate, put into the mitochondria and then metabolized aerobically. So during “recovery” from high intensity exercise, you’re actually getting an up-regulation of the aerobic system equal or greater to than you get from “aerobic” exercise. Now, that’s just talking about the metabolic aspect. True cardiovascular condition comes from peripheral adaptations – and that’s where high intensity strength training really stands out. Let’s say you take myself and an 80-year old man and we walk up two flights of stairs. When we get to the top of the stairs I’m going to feel completely fine and this elderly man, who is frail and atrophied, is going to be very winded. Well, let’s look at “why?” It’s not because his heart and blood vessels are that worse off than mine. What the real issue is has to do with the strength of our motor units. Let’s say I have 2 units of strength per motor unit, while this guy is all atrophied, so he only has 1 unit of strength per motor unit. Now let’s calculate the amount of work it takes to climb those two flights of stairs: it takes 200 units of work to make it to the top of the stairs, but because my motor units have 2 units of strength each, I only have to recruit 100 motor units to accomplish that task. His motor units have 1 unit of strength, so he has to recruit 200 motor units to accomplish the same task. My cardiovascular system, then, only has to support the work of recruiting 100 motor units, while his cardiovascular system has to support the recruitment of 200 units. The real cardiovascular benefit that can come from exercise is strengthening, so that, per unit of work that you do, the cardiac and vascular system have to support a recruitment of a smaller number of motor units to achieve that task. The real cardiovascular benefits from exercise occur as a result of peripheral adaptations not central adaptations.
The Safety of Strength Training for Those with High Blood Pressure and/or Coronary Problems
QUESTION: And that leads me to my next question, and that is in the past, perhaps because of an ignorance of the metabolic workings of the anaerobic system and its production of pyruvate, and its relation to the aerobic system, a lot of people who have had a history of high blood pressure or coronary problems have been told – even from their medical people – they should not workout with high intensity. But you don’t believe that this is something they should shy away from do you?
MCGUFF: No, not at all. And I think now we’re starting to accumulate some literature that says that is not the case; that you don’t need to be worried about it. Probably one of the best pieces of literature came from an author named Meyer, who was in the American Journal of Cardiology in June of 1999. And in this study they actually put Central Venus Catheters into patients with congestive heart failure and measured hemodynamic parameters while the person was performing high intensity leg press exercise. And what they found was cardiovascular parameters that were the exact opposite of what everyone has been warned against. Now what everyone tells you is that contracting muscle is going to be squeezing on the peripheral arteries and that’s going to increase peripheral vascular resistance, and that’s going to cause the heart to have to pump against more resistance, that’s going to drive blood pressure way high and it is going to produce a dangerous strain on the heart. And if you really understand the physiology you realize that that is a completely backwards assumption. During high intensity exercise there is an outpouring of catecholamines, adrenaline, which is Epinephrine or Norepinephrine – there’s an outpouring of these hormones and these hormones act upon the heart and the blood vessels. And there’s different receptors out on the periphery of the body that respond to these hormones in a different fashion. During high intensity exercise, those hormones act on blood vessels in the splenic circulation of your intestines, your liver, to cause vasoconstriction, meaning the blood vessel constricts and blood flow to those areas decreases. But receptors on blood vessels in working muscles, in the pulmonary tree in the lungs, do exactly the opposite: they vasodilate and they allow more blood flow to enter that area to supply the working musculature. Well the net effect is that there’s more vasodilation than there is vasoconstriction and therefore the peripheral vascular resistance, as a whole, is actually lower. And that means that the heart has to pump against less resistance, not more. Couple that with the fact that the contracting musculature with high intensity muscle contraction, milks venous blood back towards the heart. Well that increase in venous return increases the amount of blood that’s delivered on the right side of the heart, which directly determines the amount of blood that is ejected from the left side of the heart. So cardiac output is actually augmented by the increased venous return from the powerful muscular contraction. Now, if you can follow along with this, the amount of blood that is ejected from the left ventricle when the heart contracts, well, when the heart relaxes, that amount of blood washes back in a backwards direction towards the aorta with a closed aortic valve. Well at the base of the aortic valve are little holes that open into the coronary arteries that supply the heart muscle with blood. So, to the extent that you get increased venous return, you therefore increase the amount of blood that is ejected from the left side of the heart, which therefore increases the amount of blood that back flows into the coronary arteries. So high intensity strength training not only decreases peripheral vascular resistance because of the dilated blood vessels in the working musculature, you’re also augmenting venous return, which therefore augments end diastolic pressure on the left side of the heart, which augments coronary artery blood flow, which allows for a higher level of exertion to occur with an enhanced blood flow through the coronary arteries. So this is, in fact, the safest form of exercise to perform for people at cardiovascular risk.
QUESTION: And there’s been ample studies that indicate that at no time with high intensity strength training does the arterial pressure rise beyond that of well-controlled hypertension and that high intensity exercise is actually safer than treadmill exercise.
MCGUFF: Yes, and that is borne out by this article by Meyer where they monitored central pressure and there’s an article – all the way back in 1987 by a fellow named Harris, in Medical Science and Sports Exercise, 1987, June, entitled, “Physiological response to circuit weight training in borderline hypertensive subjects.” That is actually the article that I was referring to that shows that even during the throes of exertion blood pressure is not as high as one feared. What happens when you measure blood pressure with a standard blood pressure cuff and an actively contracting muscle is that that cuff is not only measuring the blood pressure inside the blood vessel, it’s also measuring the intra-muscular pressure as a result of the contraction, and this causes a false elevation in blood pressure. If you want to know what blood pressure is actually doing you do central hemodynamic monitoring, where you put a catheter in that actually measures blood pressure in the central vasculature. That way you won’t get a false elevation of blood pressure readings and that’s how you can really determine what’s going on. And that’s why these studies were so important: they looked at central hemodynamics – not something taken with a blood pressure cuff while someone is actively contracting their biceps.
QUESTION: It speaks to efficiency too. And this is why when a person comes to yours, mine or other trainer’s high intensity training facilities and is put on a “Big 5″ type of program once a week he or she has really have done all he or she needs to for their cardiovascular system to be well looked after.
MCGUFF: In my opinion that is true. I think the most important thing to realize is that the issue of enhanced venous return is HUGE, because the degree to which you enhance venous return is the degree to which you enhance coronary artery blood flow. And that’s why in people with known coronary disease I believe strength training is actually safer than treadmill based aerobic training – because while aerobic training is less intense, it’s still raisin the oxygen demand for the muscles and the oxygen demand for the myocardium. But the muscular contractions are not that intense and do not augment the venous return nearly as much as strength training does. So you’re increasing oxygen demand, but the amount of venous return coming back to the heart is not as great. And therefore the augmentation of coronary artery blood flow is not as great. And you create a situation where there can be a mismatch between oxygen demand and oxygen delivery via the coronary arteries – and that’s where you have coronary ischemia – chest pain, cardiac arrythmias – things that are actually dangerous. In a study by a gentleman named Daub, in the Journal of Cardiopulmonary Rehabilitation,1 they did strength training early after people that had had a myocardio infarction. When you actually look at that article – I can’t remember the exact numbers – but the number of people in the strength-training group that experienced chest pain or a cardiac arrythmia was one person. And that person had something called paroxismal atrial contractions, which are completely benign cardiac arrythmia. In the aerobically trained group, I can’t remember the actual number but I think it was 31 out of 43 subjects experienced some form of adverse cardiac symptom – either chest pain or cardiac arrythmia, including some dangerous cardiac arrythmias. And while they didn’t address the issue that I’m talking about, I believe the reason is that strength training augmented coronary blood flow and helped protect against that type of risk, whereas aerobic training did not augment venous return and therefore coronary artery blood flow and you had patients that were experiencing agina and arrythmia. So I think in the future – we’ve already made the transition from “It’s all aerobic training and strength training is dangerous” to now it is clearly felt that a combination of the two is the best approach. And I think as they keep exploring this further and as their minds open up to it more and more that it’s going to be strength training much more to the exclusion of any other form of exercise as being beneficial in a cardiovascular way.
QUESTION: It’s interesting too because your heart and lungs can’t differentiate whether you’re training your biceps or your calves, they’re primarily concerned with how hard they have to work to service whatever tissues are being trained.
QUESTION: And that’s always been why running up a hill is more demanding to the cardiovascular system than running on the flat, you’re actually carrying greater weight; you’re muscles are being made to contract against greater “resistance,” as there is gravity now involved to a more marked degree.
QUESTION: The McMaster University studies we cited in our book are particularly insightful as they revealed that it is the intensity –- even as little as four 30-second intervals with up to a 4-minute rest in between intervals, not a 10 or 20-minute “steady state” activity, but 30-second intervals at high intensity — that produced produced a “doubling” of the subjects’ cardiovascular endurance.
MCGUFF: And that’s absolutely true. And the thing with that is, and the thing that makes strength training so important is, that concept can be applied to strength training but in a way that is not injurious. And any form of aerobic exercise, if you were going to raise the intensity level such as in the McMaster studies, you’re going to also have to raise the forces associated with doing that kind of training to a very high degree. So in an attempt to save your heart you’re going to destroy your knees. With properly performed high intensity low force strength training you can continue to raise the intensity ad infinitum, yet not incur those types of forces that are going to result in long term injury. There’s no point in saving your heart if you’re going to cripple yourself in the process and strength training is NOT going to do that to you.
QUESTION: When you have people want to lose fat, has it been your experience that it’s inevitable that on a below-maintenance calorie diet that one will also probably lose some degree of muscle tissue – even if paying attention to the principles of intensity, volume and frequency? Is that just a given?
MCGUFF: I believe it is because you’ve got to remember that muscle is “metabolically expensive” tissue and if you are going to be at a calorie deficit you’re body is going to make some efforts to jettison its most metabolically expensive holdings as a survival reflex. Now there are things that you can do mitigate that as much as possible, including applying the appropriate exercise stimulus, but I do believe it’s [i.e., muscle loss] going to occur to some extent, especially initially in the process. But I think that will occur to a certain extent and then stop, if everything else is done properly. And then, with proper strength training combined with a modest caloric reduction that doesn’t trigger a true starvation response, over time you will have a discriminated weight loss that is almost purely fat loss. If you’re applying a stimulus to the body that says, “Hey, we need to keep muscle – we can’t jettison any more.” Because we have a stimulus that is threatful, saying that muscle needs to be around, you’re going to create a biologic message that says, “All the weight loss that we do now has to be shunted toward fat loss because we need the muscle tissue, we need bone to support the muscle tissue and we need nervous tissue to innervate the muscle tissue.” So if we send a message that says, “We’ve got to keep muscle” in the face of a caloric deficit, all of that calorie deficit will be shunted toward fat loss. But I think in the initial stages there’s always going to be a reflex to lose some lean muscle because of its metabolic expense.
QUESTION: Do you train those who might be coming to you for fat loss any differently than you might, say, those who come to you to build bigger and stronger muscles?
MCGUFF: No. For the fat loss client we just try to coach them on a modest calorie reduction, generally try to figure out what their basal metabolic requirements are going to be, subtract 500 calories off that, over time try to add 3 to 5-pounds of muscle to raise their metabolic level somewhat so that they have more latitude for behavior and a less drastic calorie reduction becomes necessary for an on-going fat loss. The point I try to make with my fat loss clients is the average person at age 35 is unhappy because they’ve gained about 35 pounds of fat since they were 20 years old. If you take that 35 pounds of fat gain – from age 20 to 35 – and figure that out on a daily basis, that’s a calorie excess of a single potato chip over that span of time. To lose bodyfat you’ve got to do the opposite: a very modest calorie reduction done in a disciplined fashion over a long range of time, combined with strength training so all the weight loss is discriminated towards fat loss. That’s our philosophy there.
QUESTION: What’s been your greatest success story in this respect?
MCGUFF: We’ve had a couple of clients lose over 100 pounds of fat.
QUESTION: Wow – over what course of time?
MCGUFF: Over the course of a year to 18-months. We had one woman that we could not get the restraining seatbelt on the MedX Overhead Press – we stretched it all the way out and we couldn’t click the seatbelt shut on her when she started. And now she’s got plenty of slack on it. We’ve had some fairly dramatic results – but we don’t take credit for that. When that kind of fat loss occurs it is because the person in question has been extraordinarily disciplined in terms of their caloric intake. We’ve just created the environment where that caloric deficit can really be shunted towards fat loss exclusively.
QUESTION: Speaking of which, in one’s quest to build and/or preserve muscle while you’re dieting, is there a particular ratio-to-bodyweight that you would recommend with regard to protein intake?
MCGUFF: No, not a specific ratio. Our book advocates eating adequate protein in the form of lean meats. I advocate in eating as close to nature as possible in terms of eating lean meats, fruits and vegetables and avoiding the types of foods that have more to do with processing and manufacturing and anything that increases their caloric density. If you eat naturally – lean meats, fruits and vegetables – the problem is going to be getting adequate calories and I think that’s important. And if you do that I think you’re going to be getting adequate protein. I also think that you’re going to be adequately carbohydrate restricted, so that you’re not getting a large amount of refined carbohydrates inducing a negative insulin response that makes it harder to mobilize bodyfat stores. So I try not to complicate that formula too much by providing formulas or specific macronutrient mixes or anything of that nature.
QUESTION: There is nothing described as “stabilizer muscles” as a subspecies of muscle in Grey’s Anatomy. So why, then, has an entire training regimen has arisen that purports to train these muscles and that “only free weights” or lying on balls can accomplish this?
MCGUFF: (laughs) Oh that is one of the most irritating subjects of all to me. I think the whole concept of “stabilizer muscles” has been popularized mostly as a marketing ploy for different training concepts and different types of training equipment. And the whole concept of “core training” is a marketing mechanism for selling devices to train the abdominal muscles, which everyone seems to be fixated on. Most people are fixated on them because they have either an express or subconscious belief in the “spot reduction” theory. All that aside, every muscle in the body – from the flexor of your pinky finger, to your rectus abdominus muscle, to your trapezius muscle – any muscle that you name can be a “stabilizer muscle.” And the way that I think of it is that a muscle is either isotonically, meaning its contracting under load and shortening; it can contract eccentrically, meaning under load and lengthening, or it can contract isometrically, in which case the muscle is actively contracting but not producing movement. Any muscle that is contracting isometrically is acting as a stabilizer.
QUESTION: Right. And given the nature of muscular actions – the filaments slide together for contraction in a fairly linear fashion when they do contract – and when they do so against progressively increasing levels of resistance, they stronger. And it doesn’t matter whether that resistance is applied via a dumbbell, a cinder block or a Nautilus machine. In other words, there’s nothing intrinsically more beneficial in using free weights or rubber balls in developing the muscles that aid in stability and, in fact, you can probably train these muscles more efficiently and efficaciously by using, say, a Nautilus machine.
MCGUFF: Correct. The whole concept of “stabilizers” or bringing stabilizers into play while you’re actively working another muscle is just a romantic notion that really doesn’t bare out in reality at all – there aren’t “just stabilizer” muscles. Any muscle can be a “stabilizer” if it’s contracting isometrically to stabilize the body from any opposing movement in the opposite direction.
QUESTION: What about “stretching?” I know a lot of people have the idea that you have to stretch separately – on its own – to develop flexibility or to warm-up prior to a workout and to “cool down” afterwards.
MCGUFF: Yeah — that’s more fitness industry crap. We go into this in Body By Science. But, for the sake of this interview, let’s define “stretching.” Stretching is the application of force on a muscle at the extremes of its range of motion. Let’s take that as our definition of stretching. Well, if you perform a proper set of high intensity strength training you’re going to be doing a full range of motion. You’re going to be using a weight that provides a meaningful load. Therefore, you’re going to be meaningfully loaded at that muscle’s position of flexion and at that muscle’s position of full extension. Therefore, the stretching is built in to the exercise itself because you have the application of force at the extremes of range of motion of that muscle. Now what most people confuse stretching for is actually what is referred to as “passive insufficiency.” And if you watch most people that are doing a “hurdler’s stretch,” for instance, you a “tugging” sensation in the hamstring muscle but this is not really true stretching. You’re just placing that muscle in a very extended position where it cannot actively contract because the opposing musculature is placed in a position of full contraction. And that produces a sensation of tugging that most people mistake as “stretching.” If you watch people stretch their lats – they’ll raise their arm over their head and bend to one side – it produces a stretching sensation, but you’re not actually stretching the lat. What you’re doing is externally rotating the scapula, so that the point of the shoulder blade is digging into the belly of the latissimus muscle and producing a sensation of pulling or tugging, which is mistaken as stretching. But it’s not stretching – you’re just taking a pointy bony prominence and pushing it into the belly of the muscle.
QUESTION: I’ve seen some studies that say that:
a) stretching does not diminish the chance of injury from exercise and
b) it does not hasten the recovery process from exercise.
MCGUFF: It does neither.
QUESTION: Let me ask your opinion on why was — or is — Nautilus such a huge advancement in bodybuilding and fitness training?
MCGUFF: There are so many reasons. Above all I would have to say the understanding of the mechanics of the musculature and moment arm issues and the use of a variable resistance cam so that muscular failure could be reached more as a result of accumulated fatigue rather than an inability to get over the hump of a mechanical sticking point of the equipment in use. I think that’s one of the biggest things is just to allow a more functional exercise by trying to get around those sticking point issues by use of a variable cam. The second is actually, for the first time in history, to have a good piece of equipment that was intellectually attached to a good exercise philosophy. Those two things placed together were unprecedented in the history of exercise.
QUESTION: Could you tell the readers something about your professional training center in South Carolina? You had mentioned what machines you have but how is it set up? How long are the workouts on average?
MCGUFF: The facility is an exclusively high intensity training facility. We use the Body By Science protocols for our repetitions and all the exercise that is done there is high intensity exercise: very brief in duration, and performed with recovery in mind. The average workout lasts 12- to- 17-minutes and most of our clients train once a week. That allows for enough recovery for almost everyone; it’s not “too much recovery” for anyone. We have maybe one or two clients that come twice a week, and we also have a fair number of clients that come once every 14 days. So the span is between a few at twice a week, the majority at once a week, a few every 14-days.
QUESTION: What philosophy of life do you subscribe to?
MCGUFF: Well I think, much like Mike Mentzer, I find the philosophy of Objectivism to be very compelling. And I subscribe to it basically because reality exists, and reality existed long before I got here. I think existence precedes consciousness and in order to be successful in the world in a true sense you have to pay attention to reality and reality’s response to your actions. And if you’re not doing that you’re not going to get the best results out of life possible.
Article copyright © 2009 John Little and Doug McGuff. All Rights Reserved.
NOTES ON TEXT:
1.) Daub WD, et al. Strength training early after myocardial infarction. J Cardiopulm Rehabil 1996 Mar-Apr; 16 (2): 100-8.