Peter W
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Kilde : http://nymag.com/news/sports/38001/
Uddrag fra Gary Taubes nye bog : Good Calories, Bad Calories: Challenging the Conventional Wisdom on Diet, Weight Control, and Disease - Knop 2007
The Scientist and the Stairmaster
Why most of us believe that exercise makes us thinner—and why we're wrong.
• By Gary Taube
Let us begin with a short quiz: a few questions to ponder during the 30 (or 60 or 90) minutes a day you spend burning off excess calories at the gym, or perhaps while feeling guilty because you’re not so engaged. If lean people are more physically active than fat people—one fact in the often-murky science of weight control that’s been established beyond reasonable doubt— does that mean that working out will make a fat person lean? Does it mean that sitting around will make a lean person fat? How about a mathematical variation on these questions: Let’s say we go to the gym and burn off 3,500 calories every week—that’s 700 calories a session, five times a week. Since a pound of fat is equivalent to 3,500 calories, does that mean we’ll be a pound slimmer for every week we exercise? And will we continue to slim down at this pace for as long as we continue to exercise?
For most of us, fear of flab is the reason we exercise, the motivation that drives us to the gym. It’s also why public-health authorities have taken to encouraging ever more exercise as part of a healthy lifestyle. If we’re fat or fatter than ideal, we work out. Burn calories. Expend energy. Still fat? Burn more. The dietary guidelines of the U.S. Department of Agriculture, for instance, now recommend that we engage in up to 60 minutes daily of “moderate to vigorous intensity” physical activity just to maintain weight—that is, keep us from fattening further. Considering the ubiquity of the message, the hold it has on our lives, and the elegant simplicity of the notion—burn calories, lose weight—wouldn’t it be nice to believe it were true? The catch is that science suggests it’s not, and so the answer to all of the above quiz questions is “no.”
Just last month, the American Heart Association and the American College of Sports Medicine published joint guidelines for physical activity and health. They suggested that 30 minutes of moderate physical activity five days a week is necessary to “promote and maintain health.” What they didn’t say, though, was that more physical activity will lead us to lose weight. Indeed, the best they could say about the relationship between fat and exercise was this: “It is reasonable to assume that persons with relatively high daily energy expenditures would be less likely to gain weight over time, compared with those who have low energy expenditures. So far, data to support this hypothesis are not particularly compelling.” In other words, despite half a century of efforts to prove otherwise, scientists still can’t say that exercise will help keep off the pounds.
The 30 minutes recommended by the AHA-ACSM report is a departure from the recent guidelines of other authoritative organizations—the Institute of Medicine of the National Academies and the International Association for the Study of Obesity—both of which, like the USDA, have recommended that we exercise for up to 60 minutes a day to avoid what the USDA calls “unhealthy weight gain.” But the reason for this 60-minute recommendation is precisely that so little evidence exists to support the notion that exercising less has any effect.
The report that these experts cite most often as grounds for their assessments was published in 2000 by two Finnish researchers who surveyed all the relevant research on exercise and weight of the previous twenty years. Yet the Finnish report, the most scientifically rigorous review of the evidence to date, can hardly be said to have cleared up the matter. When the Finnish investigators looked at the results of the dozen best-constructed experimental trials that addressed weight maintenance—that is, successful dieters who were trying to keep off the pounds they had shed—they found that everyone regains weight. And depending on the type of trial, exercise would either decrease the rate of that gain (by 3.2 ounces per month) or increase its rate (by 1.8 ounces). As the Finns themselves concluded, with characteristic understatement, the relationship between exercise and weight is “more complex” than they might otherwise have imagined.
This is not to say that there aren’t excellent reasons to be physically active, as these reports invariably point out. We might just enjoy exercise. We may increase our overall fitness; we may live longer, perhaps by reducing our risk of heart disease or diabetes; we’ll probably feel better about ourselves. (Of course, this may be purely a cultural phenomenon. It’s hard to imagine that the French, for instance, would improve their self-esteem by spending more time at the gym.) But there’s no reason to think that we will lose any significant amount of weight, and little reason to think we will prevent ourselves from gaining it.
• Next: The post-workout hormone that is actually feeding your fat cells
The one thing that might be said about exercise with certainty is that it tends to makes us hungry. Maybe not immediately, but eventually. Burn more calories and the odds are very good that we’ll consume more as well. And this simple fact alone might explain both the scientific evidence and a nation’s worth of sorely disappointing anecdotal experience.
It’s difficult to get health authorities to talk about the disconnect between their official recommendations and the scientific evidence that underlies it because they want to encourage us to exercise, even if their primary reason for doing so is highly debatable. Steve Blair, for instance, a University of South Carolina exercise scientist and a co-author of the AHA-ACSM guidelines, says he was “short, fat, and bald” when he started running in his thirties and he is short, fatter, and balder now, at age 68. In the intervening years, he estimates, he has run close to 80,000 miles and gained about 30 pounds.
When I asked Blair whether he thought he might be leaner had he run even more, he had to think about it. “I don’t see how I could have been more active,” he said. “Thirty years ago, I was running 50 miles a week. I had no time to do more. But if I could have gone out over the last couple of decades for two to three hours a day, maybe I would not have gained this weight.” And maybe he would have anyway. If we trust the AHA-ACSM report he co-authored, there is little reason to believe that the amount he runs makes any difference. Nonetheless, Blair personally believes he would be fatter still if he hadn’t been running. Why?
There was a time when virtually no one believed exercise would help a person lose weight. Until the sixties, clinicians who treated obese and overweight patients dismissed the notion as naïve. When Russell Wilder, an obesity and diabetes specialist at the Mayo Clinic, lectured on obesity in 1932, he said his fat patients tended to lose more weight with bed rest, “while unusually strenuous physical exercise slows the rate of loss.”
The problem, as he and his contemporaries saw it, is that light exercise burns an insignificant number of calories, amounts that are undone by comparatively effortless changes in diet. In 1942, Louis Newburgh of the University of Michigan calculated that a 250-pound man expends only three calories climbing a flight of stairs—the equivalent of depriving himself of a quarter-teaspoon of sugar or a hundredth of an ounce of butter. “He will have to climb twenty flights of stairs to rid himself of the energy contained in one slice of bread!” Newburgh observed. So why not skip the stairs, skip the bread, and call it a day?
More-strenuous exercise, these physicians further argued, doesn’t help matters—because it works up an appetite. “Vigorous muscle exercise usually results in immediate demand for a large meal,” noted Hugo Rony of Northwestern University in his 1940 textbook, Obesity and Leanness. “Consistently high or low energy expenditures result in consistently high or low levels of appetite. Thus men doing heavy physical work spontaneously eat more than men engaged in sedentary occupations. Statistics show that the average daily caloric intake of lumberjacks is more than 5,000 calories, while that of tailors is only about 2,500 calories. Persons who change their occupation from light to heavy work or vice versa soon develop corresponding changes in their appetite.” If a tailor becomes a lumberjack and, by doing so, takes to eating like one, why assume that the same won’t happen, albeit on a lesser scale, to an overweight tailor who decides to work out like a lumberjack for an hour a day?
Credit for why we came to believe otherwise goes to one man, Jean Mayer, who began his career at Harvard in the early fifties, went on to become the most influential nutritionist in the country, and then, for sixteen years, served as president of Tufts University (where there is now a Jean Mayer USDA Human Nutrition Research Center on Aging). As an authority on human weight regulation, Mayer was among the very first of a new breed, a type that has since come to dominate the field. His predecessors—Wilder, Rony, Newburgh, and others—had all been physicians who worked closely with obese and overweight patients. Mayer was not. His training was in physiological chemistry; he had obtained a doctorate at Yale with a dissertation on the interrelationship of vitamins A and C in rats. In the ensuing decades, he would publish hundreds of papers on different aspects of nutrition, including why we get fat, but he never had to reduce obese patients as part of his clinical obligation, and so his hypotheses were less fettered by anecdotal or real-life experience.
As early as 1953, after just a few years of research on laboratory mice, Mayer began extolling the virtues of exercise for weight control. By 1959, the New York Times was crediting him with having “debunked [the] popular theories” that exercise played little role in weight control. Mayer knew that the obese often eat no more than the lean and occasionally even less. This seemed to exclude gluttony as a cause of their weight gain, which meant that these fat people had to be less physically active. Otherwise, how could they take in more calories than they expend and so become fat?
• Next: Does exercise stimulate your appetite?
Through the sixties, Mayer documented the relationship between inactivity and the overweight. He noted that fat high-school girls ate “several hundred calories less” than lean classmates. “The laws of thermodynamics were, however, not flouted by this finding,” he wrote, because the obese girls expended less energy than the lean: They were much less active; they spent four times as many hours watching television. Mayer also studied infants. “The striking phenomenon is that the fatter babies were quiet, placid babies that had moderate intake,” Mayer reported, “whereas the babies who had the highest intake tended to be very thin babies, cried a lot, moved a lot, and became very tense.” Thus, Mayer concluded, “some individuals are born very quiet, inactive, and placid and with moderate intake get fat, and some individuals from the very beginning are very active and do not get particularly fat even with high intakes.”
It was Mayer who pioneered the now-ubiquitous practice of implicating sedentary living as the “most important factor” leading to obesity and the chronic diseases that accompany it. Modern Americans, said Mayer, were inert compared with their “pioneer forebears” who were “constantly engaged in hard physical labor.” Every modern convenience, by this logic, from power windows to the electric toothbrush, only serves to minimize the calories we expend. “The development of obesity,” Mayer wrote in 1968, “is to a large extent the result of the lack of foresight of a civilization which spends tens of billions annually on cars, but is unwilling to include a swimming pool and tennis courts in the plans of every high school.”
Mayer’s hypothesis always had shortcomings, but they were ignored for the same reasons they still are—who wants to openly question the idea that physical activity is a panacea? The first issue is a logical one: That conclusion that the fatter we are, the more sedentary we’re likely to be is actually a correlation; it tells us nothing about what is cause and what is effect. “It is a common observation,” noted Rony in 1941, “that many obese persons are lazy, i.e., show decreased impulse to muscle activity. This may be, in part, an effect that excess weight would have on the activity impulse of any normal person.” Equally possible is that obesity and physical inactivity are both symptoms of the same underlying cause.
This logical problem was then obscured by Mayer’s all-out attack on the role of hunger. Mayer acknowledged that exercise could make us hungrier, but he said it wasn’t necessarily the case. This was the heart of Mayer’s message—a purported loophole in the relationship between appetite and physical activity. “If exercise is decreased below a certain point, food intake no longer decreases,” said Mayer. “In other words, walking one half-hour a day may be equivalent to only four slices of bread, but if you don’t walk the half-hour, you still want to eat the four slices.”
Mayer based this conclusion on two (and only two) of his own studies from the mid-fifties. The first purported to demonstrate that laboratory rats exercised for a few hours every day will eat less than rats that don’t exercise at all. But this would never be replicated. In more recent experiments, the more rats run the more rats eat; weights remain unchanged. And when rats are retired from these exercise programs, they eat more than ever and gain weight with age more rapidly than rats that were allowed to remain sedentary. With hamsters and gerbils, exercise increases body weight and body-fat percentage. So exercising makes these particular rodents fatter, not leaner.
Mayer’s second study was an assessment of the diet, physical activity, and weights of workers and merchants at a mill in West Bengal, India. This article is still cited—by the Institute of Medicine, for instance—as perhaps the only existing evidence that physical activity and appetite do not necessarily go hand in hand. But it, too, has never been replicated, despite (or perhaps because of) a half-century of improvements in methods of assessing diet and energy expenditure in humans.
It helped that Mayer promoted his pro-exercise message with a fervor akin to a moral crusade. In 1966, Mayer was the primary author of a U.S. Public Health Service report advocating increased physical activity along with diet as the best way to lose weight. In 1969, Mayer chaired Richard Nixon’s White House Conference on Food, Nutrition, and Health. “The successful treatment of obesity must involve far-reaching changes in lifestyle,” the conference report concludes. “These changes include alterations of dietary patterns and patterns of physical activity.” In 1972, Mayer began writing a syndicated newspaper column on nutrition: Exercise, Mayer now wrote, sounding suspiciously like a diet doctor selling a patent claim, will make “weight melt away faster,” and “contrary to popular belief, exercise won’t stimulate your appetite.”
• Next: The "exercise explosion" grips America.
Our culture of physical exercise began only in the late sixties, coincident with Mayer’s crusade, which explains why our parents might not have been quite so devoted to the idea of spending their leisure time perspiring profusely. In 1977, the New York Times was covering the “exercise explosion” that had come about because the conventional wisdom of the sixties that exercise was “bad for you” had been transformed into the “new conventional wisdom—that strenuous exercise is good for you.” When the Washington Post estimated in 1980 that 100 million Americans were partaking in the “new fitness revolution”—coincident with the start of the current obesity epidemic—it also noted that most of them “would have been derided as ‘health nuts’" only a decade earlier.
Meanwhile, the evidence simply never came around to support Mayer’s hypothesis, even though our beliefs did. My favorite study of the effect of physical activity on weight loss was published in 1989 by a team of Danish researchers. Over the course of eighteen months the Danes trained nonathletes to run a marathon. At the end of this training period, the eighteen men in the study had lost an average of five pounds of body fat. As for the nine women subjects, the Danes reported, “no change in body composition was observed.” That same year, F. Xavier Pi-Sunyer, then director of the St. Luke’s–Roosevelt Hospital Obesity Research Center in New York, reviewed the studies on exercise and weight, and his conclusion was identical to that of the Finnish review’s eleven years later: “Decreases, increases, and no changes in body weight and body composition have been observed,” Pi-Sunyer reported.
Granted, all this still doesn’t explain why we bought into Mayer’s idea that we could exercise more and not compensate by eating more. One simple reason is that the health reporters bought it, and we were reading their articles, not the research literature itself. In 1977, for instance, the National Institutes of Health hosted its second conference on obesity and weight control. “The importance of exercise in weight control is less than might be believed,” the assembled experts concluded, “because increases in energy expenditure due to exercise also tend to increase food consumption, and it is not possible to predict whether the increased caloric output will be outweighed by the greater food intake.” That same year, The New York Times Magazine reported that there was “now strong evidence that regular exercise can and does result in substantial and—so long as the exercise is continued—permanent weight loss.” By 1990, a year after Pi-Sunyer’s pessimistic assessment of the evidence, Newsweek was declaring exercise an “essential” element of any weight-loss program, and the Times had stated that on those infrequent occasions “when exercise isn’t enough” to lose weight, “you must also make sure you don’t overeat.”
As for the authorities themselves, the primary factor fueling their belief in the weight-maintaining benefits of exercise was their natural reluctance to acknowledge otherwise. Although one couldn’t help but be “underwhelmed by” the evidence, as Mayer’s student Judith Stern, a UC Davis nutritionist, wrote in 1986, it would be “shortsighted” to say that exercise was ineffective because it meant ignoring the possible contributions of exercise to the prevention of obesity and to the maintenance of weight loss that might be induced by diet. These, of course, had never been demonstrated either, but they hadn’t been ruled out. This faith-based philosophy came to dominate scientific discussions on exercise and weight, but it couldn’t be reconciled with the simple notion that appetite and calories consumed will increase with an increase in physical activity. Hence, the idea of working up an appetite was jettisoned. Clinicians, researchers, exercise physiologists, even personal trainers at the local gym took to thinking and talking about hunger as though it were a phenomenon exclusive to the brain, a question of willpower (whatever that is), not the natural consequence of a body trying to replenish itself with energy.
Ultimately, the relationship between physical activity and fatness comes down to the question of cause and effect. Is Lance Armstrong excessively lean because he burns off a few thousand calories a day cycling, or is he driven to expend that energy because his body is constitutionally set against storing calories as fat? If his fat tissue is resistant to accumulating calories, his body has little choice but to burn them as quickly as possible: what Rony and his contemporaries called the “activity impulse”—a physiological drive, not a conscious one. His body is telling him to get on his bike and ride, not his mind. Those of us who run to fat would have the opposite problem. Our fat tissue wants to store calories, leaving our muscles with a relative dearth of energy to burn. It’s not willpower we lack, but fuel.
For the last 60 years, researchers studying obesity and weight regulation have insisted on treating the human body as a thermodynamic black box: Calories go in one side, they come out the other, and the difference (calories in minus calories out) ends up as either more or less fat. The fat tissue, in this thermodynamic model, has nothing to say in the matter. Thus the official recommendations to eat less and exercise more and assuredly you’ll get thinner. (Or at least not fatter.) And in the strict sense this is true—you can starve a human, or a rat, and he will indeed lose weight—but that misses the point. Humans, rats, and all living organisms are ruled by biology, not thermodynamics. When we deprive ourselves of food, we get hungry. When we push ourselves physically, we get tired.
Our bodies, like all living organisms, have evolved a fantastically complex web of feedback loops. These physiological mechanisms serve fundamentally to work against the inevitable pull of thermodynamics (which is entropy, a.k.a. death) and so make life possible. The necessary condition of life, as the great French physiologist Claude Bernard noted 140 years ago, is to keep the internal environment of an organism stable and conducive to life, regardless of what’s happening on the outside. This is what the Harvard physiologist Walter Cannon, in the thirties, called homeostasis—or the “wisdom of the body,” as he put it. “Somehow the unstable stuff of which we are composed,” Cannon wrote, “had learned the trick of maintaining stability.”
• Next: How fat affects our ability to lose weight.
The key is that among the many things regulated in this homeostatic system—along with blood pressure and blood sugar, body temperature, respiration, etc.—is the amount of fat we carry. From this biological or homeostatic perspective, lean people are not those who have the willpower to exercise more and eat less. They are people whose bodies are programmed to send the calories they consume to the muscles to be burned rather than to the fat tissue to be stored—the Lance Armstrongs of the world. The rest of us tend to go the other way, shunting off calories to fat tissue, where they accumulate to excess. This shunting of calories toward fat cells to be stored or toward the muscles to be burned is a phenomenon known as fuel partitioning.
The job of determining how fuels (glucose and fatty acids) will be used, whether we will store them as fat or burn them for energy, is carried out primarily by the hormone insulin in concert with an enzyme known technically as lipoprotein lipase—LPL, for short. (Sex hormones also interact with LPL, which is why men and women fatten differently.)
In the eighties, biochemists and physiologists worked out how LPL responds to exercise. They found that during a workout, LPL activity increases in muscle tissue, and so our muscle cells suck up fatty acids to use for fuel. Then, when we’re done exercising, LPL activity in the muscle tissue tapers off and LPL activity in our fat tissue spikes, pulling calories into fat cells. This works to return to the fat cells any fat they might have had to surrender—homeostasis, in other words. The more rigorous the exercise, and the more fat lost from our fat tissue, the greater the subsequent increase in LPL activity in the fat cells. Thus, post-workout, we get hungry: Our fat tissue is devoting itself to restoring calories as fat, depriving other tissues and organs of the fuel they need and triggering a compensatory impulse to eat. The feeling of hunger is the brain’s way of trying to satisfy the demands of the body. Just as sweating makes us thirsty, burning off calories makes us hungry.
This research has never been controversial. It’s simply been considered irrelevant by authorities, all too often lean, who have been dead set on blaming fatness on some combination of gluttony, sloth, and perhaps a little genetic predisposition thrown in on the side. But contemplating the means by which we might lose weight without considering the hormonal regulation of fat tissue is like wondering why children grow taller without considering the role of growth hormones. Or, for that matter, like trying to explain the record-breaking triumphs of modern athletes—Barry Bonds, say—and never considering the possibility that steroid hormones (or human growth hormone or insulin) might be involved.
If it’s biology, and not a lack of willpower, that explains why exercise fails so many of us as a weight-loss tool, then we can still find reason for optimism. Since insulin is the primary hormone affecting the activity of LPL on our cells, it’s not surprising that insulin is the primary regulator of how fat we get. “Fat is mobilized [from fat tissue] when insulin secretion diminishes,” the American Medical Association Council on Foods and Nutrition explained back in 1974, before this fact, too, was deemed irrelevant to the question of why we gain weight or the means to lose it. Because insulin determines fat accumulation, it’s quite possible that we get fat not because we eat too much or exercise too little but because we secrete too much insulin or because our insulin levels remain elevated far longer than might be ideal.
To be sure, this is the same logic that leads to other unconventional ideas. As it turns out, it’s carbohydrates—particularly easily digestible carbohydrates and sugars—that primarily stimulate insulin secretion. “Carbohydrates is driving insulin is driving fat,” as George Cahill Jr., a retired Harvard professor of medicine and expert on insulin, recently phrased it for me. So maybe if we eat fewer carbohydrates—in particular the easily digestible simple carbohydrates and sugars—we might lose considerable fat or at least not gain any more, whether we exercise or not. This would explain the slew of recent clinical trials demonstrating that dieters who restrict carbohydrates but not calories invariably lose more weight than dieters who restrict calories but not necessarily carbohydrates. Put simply, it’s quite possible that the foods—potatoes, pasta, rice, bread, pastries, sweets, soda, and beer—that our parents always thought were fattening (back when the medical specialists treating obesity believed that exercise made us hungry) really are fattening. And so if we avoid these foods specifically, we may find our weights more in line with our desires.
As for those people who insist that exercise has been the key to their weight-loss programs, the one thing we’d have to wonder is whether they changed their diets as well. Rare is the person who decides the time has come to lose weight and doesn’t also decide perhaps it’s time to eat fewer sweets, drink less beer, switch to diet soda, and maybe curtail the kind of carb-rich snacks—the potato chips and the candy bars—that might be singularly responsible for driving up their insulin and so their fat.
For the rest of us, it may be time to take a scientific or biological view of our excesses rather than a biblical one. The benefits of exercise include the joys of virtuousness. I worked out today, therefore I can eat fattening foods to my heart’s content. But maybe the causality is reversed here too. Maybe it’s because we eat foods that fatten us that the workout becomes a necessity, the best we can do in the battle against our own fat tissue.
Kilde : http://nymag.com/news/sports/38001/
PW
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En mening om sukker - som parameter for overvægt.
PW
Fra:www.medicalnewstoday.com/articles/79272.php
Diet Or Exercise? New Study Finds Sugar Is Important In Obesity, UK
10 Aug 2007
Scientists at the Medical Research Council have found that eating more sugar is associated with obesity. Although this may seem obvious, previous studies, which relied on self-reporting of diet, had not shown that this was the case. But researchers from the Medical Research Council and University of Cambridge looking into the links between diet and cancer have developed a new way of objectively measuring sugar consumption. This is important in establishing the cause of the UK's epidemic of obesity: lack of exercise or over-eating.
The team developed a new way of objectively measuring sugar consumption. Their findings about how much sugar overweight people consume are published in the journal Cancer Epidemiology, Biomarkers and Prevention.
Until now it had been very difficult to assess food intake, particularly sugar consumption, in large populations. Data from surveys seemed to show that as weight and body mass index increased, people underestimated their total food intake, including the amount of sugar they ate.
The team has developed a new urine test which allows them to work out how much sugar large numbers of people are eating for the first time. They measure the levels of urinary sucrose and fructose (two types of sugar) in spot urine samples.
Using data from hundreds of volunteers from the European Prospective Investigation of Cancer (EPIC) study, researchers have combined information from diet self-reporting with data from the urine and blood samples. They found that obese people underestimated the amount of sugar they consumed, while overestimating the amount of vitamin C they took in each day.
Professor Sheila Bingham, who led the study said: "The spot urine and blood tests established that obese people consume more sugar and less vitamin C than their thinner counterparts, but this did not show up when asked. Although obese people may have a less active lifestyle than people of normal weight, reports about what they ate were less accurate than those from their normal weight counterparts."
The 20% of people tested who consumed the least sugar ate about 76g per day but the 20% who ate the most took in an average 207g, nearly three times as much.
Professor Bingham, from the MRC Dunn Human Nutrition Unit and EPIC study continued: "These results show what many have suspected for some time: obese people are not able to tell us what they actually eat. If we are to tackle the scourge of obesity, both exercise and diet need to be taken into account."
1. Publication details
Epidemiologic assessment of sugars consumption using biomarkers: comparisons of obese and nonobese individuals in the European Prospective Investigation of Cancer Norfolk. Sheila Bingham, Robert Luben, Ailsa Welch, Natasa Tasevska, Nick Wareham and Kay Tee Khaw. Cancer Epidemiol Biomarkers Prev; 16(8) August 2007.
2. Definitions
Sucrose and fructose are types of sugar. Sucrose is mostly found in table sugar, sugar used in cooking, preserves, cakes, biscuits, confectionary and soft drinks, while fructose is found in fruit and fruit products.
3. Medical Research Council
The Medical Research Council is dedicated to improving human health through excellent science. It invests on behalf of the UK taxpayer. Its work ranges from molecular level science to public health research, carried out in universities, hospitals and a network of its own units and institutes. The MRC liaises with the Health Departments, the National Health Service and industry to take account of the public's needs. The results have led to some of the most significant discoveries in medical science and benefited the health and wealth of millions of people in the UK and around the world.
Article URL: http://www.medicalnewstoday.com/articles/79272.php
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Hr. Endofinjunkie
Vedrørende deres achillessener.
Mon det kunne være en problematik i denne i retning!
Et uskønt link
PW
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-789
Det er et direkte citat fra bogen - men
Poul-Erik Paulev bruger Walt & Wyndham til at estimere Max-VO2 for en atlet der løber 20km på en time
-Ebeltoft
Et forsigtigt forsøg på at anvende – Walt & Wyndham
TBW=84KG (Ebeltoft)
V =11,25km/t (3000m/16min)
Indsættes i Walt & Wyndham
VO2=3,56l/m dvs. det koster netto 3,56l/m at løbe 3000m på 16min.
Veltrænede Ebeltoft kan løbe på 97% af Max-VO2
3,56l/m/0,97=3,67l/m dvs. Ebeltoft skal (mindst) have Max-VO2 3,67l/m eller 43,7ml/kg
PW
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Walt & Wyndham:
VO2=-0,419+0,03257xTBW+0,000117xTBWXVxV
VO2=iltoptagelse
TBW=total legmesvægt i kg
V =løbehastighed km/time
estimat for atleter der løber på flad bane i længere tid.
Kilde: Paul-Erik Paulev - Løb for den trænede - men gør det afslappet (1979)
PW
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Mon ikke en atlet af Armstrong's format bør lave en kontrolleret "nedtrapning"
af træningen.
Jeg synes at huske, måske forkert, at Hans-Henrik Ørsted efter at være stoppet
træning led af opsvulmede underben.
Efter nogen tid fandt man ud af, at opsvulmningen skyldtes, at kroppen stadig
producerede oxidative enzymer til "200km på cykel om dagen".
Måske nogen af Boardets cykel-experter kan be-/afkræfte dette.
PW
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Til inspiration :
Special Treat: A Program from Bill Starr
Thanks to Mike Rinaldi for helping me track down Mr. Starr. I wrote him a letter, ordered a copy of "Defying Gravity". He autographed the book, was very helpful with my questions and send me a copy of the following program.
Hopkins Football 2000 Summer Lifting: Upperclassmen
by Bill Starr
Monday (Heavy Day)
Squats 5 x 5; 1 x 8 (back-off set)
Bench Press: Change your routine every week. Always do three sets of five as warm-ups then do three sets of heavier triples, doubles or singles. Some weeks you might want to find a work weight and do it for 3-5 sets of five. Do one or two back-off sets of eight
Back Work: Alternate deadlifts with power clean and clean high pulls every other week. Change up the reps on the deadlifts each time you do them. Do five sets of five, two sets of five, followed by three sets of 3, or four sets of eight. Work five sets of five on the power cleans, then do four sets of three on the clean high pull. You should be doing fifty more pounds on the high pull on your very first set than you used for your last power clean and aim at using 100 more pounds on your final set.
Auxiliary Work: Incline Dumbbells: Change these around also. One week do three sets of twelve or fifteen, then another do two sets of twenty. Do NOT do any less than 10 reps however.
Tuesday (Light Day)
Power Snatches: Two sets of five, then four to five sets of three. As long as you are maintaining goof form, you can do extra sets but when the form gets sloppy, move on to the high pulls.
(Note from Coach Margraff—“make sure you know what you are doing with this lift. Incoming freshman are not to attempt this lift until they are properly taught the technique here at Hopkins by Bill Starr)
Snatch Grip High Pulls: Five sets of three, again trying to handle at least 100 pounds more on your final set over what you power snatched for your last set
Overhead Press: Change the set and rep sequence like you did on the bench press. Until you get your form down, do five sets of five. An excellent formula to improve this lift is to do three sets of five as warm-ups, then select a work weight and do five sets of three. Follow these with one back-off set of eight. If you make all your sets, move the weight up five pounds the next week. Stay with the strict presses until you are able to handle 200 x 3, then you can add in some push presses. But the strict presses are more beneficial until you reach that strength level.
Baby Cows: Start doing three to five sets of thirty reps and if possible alternate the standing and seated calf machines.
Chin-ups: Do four sets of all you can do. Try to add at least one rep, total, to each workout and these will steadily move up.
Wednesday (Light Day)
Squats: Five sets of five, using 50 lbs less than you did on Monday or do Front Squats, three sets of five followed by three sets of heavier threes
Good Mornings: Four sets of eight. Remember you want to keep your top set of eight at 50% of your best squat
Incline Bench: Follow the guidelines set down for the bench press on Monday. Change the routine weekly but always look for a PR
Dips: One set without weight, then start adding resistance for three or four more sets. Do eights, fives and threes. In order for dips to help your other lifts, you have to move past 100 for reps
Beach Work: Do two or three sets for your triceps and biceps, but don’t get nuts on these for you are already doing lots for you upper arms and adding in too much will not help, but hurt. For the triceps: straight-arm pullover or pushdowns on the lat machine are good. Any type of curling is useful for the biceps and some reverse curls are beneficial for forearm development. Keep the reps high, twenties, fifteens, and never less than ten
Friday (Medium Day)
Squats: Three sets of five followed by two sets of threes and one back-off set of eight. Try to move your triple up five to ten pounds each week and come back the following Monday and do that same weight for five reps.
Hang Cleans: These are optional. If you think you need more work on your power clean form, do three or four sets of five before doing your shrugs. Always do these before shrugging.
Shrugs: Five to six sets of five. Alternate the Hawaiian kind with the “in the rack” type, if possible
Bench Press:Four sets of eight followed by two sets of doubles
Close-grip Bench Press OR Overhead Press: Do NOT do both!! You can alternate these every other week. On the close-grips, do three or four sets of eight. On the overhead presses, do five sets of five
Beach Work: Optional. If you have some energy left over at this stage of the week, you can add in more curls, triceps or chins. But don’t overdo it or you will be shot for Monday.
ALL WORKOUTS:
Abdominal Work: Include ab work at every workout. In fact you can do something for your abs every day. Be sure to hit the high and low portions of your midsection every time. High reps are better than multiple sets of lower reps.
Stretching: Spend time stretching after each workout. It is also a good idea to start doing some stretching during the workout in-between sets.
Leg Machines: If you have them available, utilize the leg machines at least twice a week. Leg extension, leg curl and adductor for two sets of twenty.
PW
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Spinx : Måske kan du hente inspiration i Christian Thibaudeau's
8 Weeks to a Record Bench.
(ttp://www.t-nation.com/readTopic.do;jsessionid=1BDE72F586548152C1B85D8E5859318B.titan?id=539885)
PW
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Stubbe : Gå til (http://transfedt.dk/Sitemap.htm) nederst
(http://transfedt.dk/Slangetaemmer.dk.htm) her et 'CV' for hr. Jan Petersen
PW
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jcs:
Jeg er næsten også sikker på, at metoden oprindeligt er tiltænkt sprinttræning
JA - hurtigløb¨på skøjter
PW
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Fra Schweiz om svømning (http://www.svl.ch/svlimmat_ratind.html)
Om styrketræning i svømning (http://www.svl.ch/Kraft/)
Bemærk Jean-Pierre Egger's lille indlæg (http://www.svl.ch/Kraft/KrafttrainingSchwimmer.pdf)
PW
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Poliquin:
If you serratus anterior is weak it is normally also reflected by a poor performance in the military press exercise. You should be able to military press 70% of your bench press performance.
(www.charlespoliquin.net/ articles/the-lost-poliquin-files-page2.html)
PW
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Zoa
Du kan måske noget i denne retning du søger ?
PW
Bulgarian loading secrets for strength
By Christian Thibaudeau
Over the past 20 years, Bulgaria has developed some of strongest Olympic lifters on the face of the earth. Year after year they are in contention to win the best team award at the world championships. Even more impressive is the fact that their first team constantly finishes in the top 3 world ranking while their "backup lifters" also win medals for Qatar (Bulgaria loaned lifters to Qatar for an hefty sum of money). Bad mouths will be soon to associate this domination with steroids. Let me be clear on this: at the elite level in Olympic lifting almost everybody uses steroids and the steroids available in Bulgaria are not different from those available anywhere else! Furthermore, Bulgaria is a small country (approximately 7-8 million peoples) so it doesn?t have the talent pool that countries like China or the former Soviet Union has/had. Evidently, the fact that they are superior stems from somewhere else.
Bulgarian lifters use a very atypical loading scheme. A form of loading that I call Bulgarian wave loading. Those who heard a few things about Bulgarian lifters are led to believe that they always lift maximal weights, 7 days a week. That is not entirely true. Bulgaria lifters go for their daily max at every 2 sessions. However that daily max is not necessarily a personal best attempt, rather it's a load that is very challenging for that day. In most cases, it equates to 85-95% of their competitive max.
In their "heavy" sessions Bulgarian lifters will build up to their daily max. This max is not an end in itself, rather it is the starting point of their training: the daily max is used to calculate the training load for the rest of the day. Once a lifter reaches his max, he backs down 25-40lbs and do 3-5 sets of 2-3 reps. That are the money sets! With this form of training your daily session is always adapted to your present capacities.
Bulgarian wave loading parameters
Sets 1 - 3: Warm-ups with a load lower than 60% of the competition max/personal record
Sets 4 - 7: Work up to the daily 1 rep maximum
Sets 8-9: Daily max - 40lbs for 3 reps
Sets 10-12: Daily max - 25lbs for 2 reps
They will use this form of loading for 3 daily exercises. On "lighter" days they will do technique work with a relatively light load (60-70%). They will not have a precise number of sets to do. They do 3 different exercises, allocating 15-20 minutes per exercise and they do however sets they feel comfortable doing that day. This is not unlike Charles Staley?s EDT, and it is also a technique used by Canadian weightlifting coach Pierre Roy.
Adapting the Bulgarian system to your capacities
Obviously you do not have the benefits of using anabolic aids nor can you spend most of your day training like Bulgarian lifters do. However the basic method can still be applied. You just need to reduce the training frequency a bit.
It is not a method limited to the Olympic lifts. If anything it works better for basic strength lifts like the squat, bench press and deadlift.
Bulgarian loading is for strength gains, not for size gains. Athletes seeking a boost in their strength without too much bodyweight gain will be well served by the method.
A typical modified Bulgarian strength program
Day 1. Hard session
A. Power clean from hang
Sets 1 - 3: Warm-ups with a load lower than 60% of the competition max/personal record
Sets 4 - 7: Work up to the daily 1 rep maximum
Sets 8-9: Daily max - 40lbs for 3 reps
Sets 10-12: Daily max - 25lbs for 2 reps
2 minutes of rest between sets.
10 minutes break between exercise A. and exercise B.
B. Back squat
Sets 1 - 3: Warm-ups with a load lower than 60% of the competition max/personal record
Sets 4 - 7: Work up to the daily 1 rep maximum
Sets 8-9: Daily max - 40lbs for 3 reps
Sets 10-12: Daily max - 25lbs for 2 reps
2 minutes of rest between sets.
10 minutes break between exercise B. and exercise C.
C. 1/2 rack deadlift
Sets 1- 3: Warm-ups with a load lower than 60% of the competition max/personal record
Sets 4 - 7: Work up to the daily 1 rep maximum
Sets 8-9: Daily max - 40lbs for 3 reps
Sets 10-12: Daily max - 25lbs for 2 reps
2 minutes of rest between sets.
Day 2. Easy session
A. Bench press
3-4 reps
60-70% of maximum
15 minutes, do as many sets as you feel comfortable doing
B. Push press
3-4 reps
60-70% of maximum
15 minutes, do as many sets as you feel comfortable doing
C. Incline press
3-4 reps
60-70% of maximum
15 minutes, do as many sets as you feel comfortable doing
Day 3. Easy session
A. Power clean from hang
3-4 reps
60-70% of maximum
15 minutes, do as many sets as you feel comfortable doing
B. Romanian deadlift
3-4 reps
60-70% of maximum
15 minutes, do as many sets as you feel comfortable doing
C. Barbell rowing
3-4 reps
60-70% of maximum
15 minutes, do as many sets as you feel comfortable doing
Day 4. Hard session
A. Bench press
Sets 1 - 3: Warm-ups with a load lower than 60% of the competition max/personal record
Sets 4 - 7: Work up to the daily 1 rep maximum
Sets 8-9: Daily max - 40lbs for 3 reps
Sets 10-12: Daily max - 25lbs for 2 reps
2 minutes of rest between sets.
10 minutes break between exercise A. and exercise B.
B. Push press
Sets 1 - 3: Warm-ups with a load lower than 60% of the competition max/personal record
Sets 4 - 7: Work up to the daily 1 rep maximum
Sets 8-9: Daily max - 40lbs for 3 reps
Sets 10-12: Daily max - 25lbs for 2 reps
2 minutes of rest between sets.
10 minutes break between exercise A. and exercise B.
C. Close grip bench press
Sets 1 - 3: Warm-ups with a load lower than 60% of the competition max/personal record
Sets 4 - 7: Work up to the daily 1 rep maximum
Sets 8-9: Daily max - 40lbs for 3 reps
Sets 10-12: Daily max - 25lbs for 2 reps
2 minutes of rest between sets.
10 minutes break between exercise A. and exercise B.
Training Split
Ideally you would follow this split:
Monday: Day 1
Tuesday: Day 2
Wednesday: off
Thursday: Day 3
Friday: Day 4
Saturday: off
Sunday: off
This will allow for maximum recovery between hard sessions and as a result, constant progress!
The choice of exercise is up to you, depending on your goals you may want to vary exercise selection. But the important thing is to understand the concept. And do no forget to use both hard and easy sessions!
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Cilius
Søg på Insulin Index
PW
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På linie med ATJ:
SHRUGS
Your trapezius muscles (called "traps") elevate and support your shoulder girdle (i.e., pull your shoulders toward your ears). Simply hold a bar in front of you and "shrug" your shoulders straight upwards. You don't have to rotate your shoulders -- just shrug.
An alternative method is to shrug with heavy dumbbells while either seated or standing. The straight bar must be held out in front of you, while seated dumbbell shrugs allow the arms to hang naturally at your sides. This makes dumbbell shrugs a bit more comfortable and definitely easier on your low back. Holding a heavy bar in front of you requires strong contraction of your erector spinae muscles.
Normal shrugging technique (as explained above) activates the two upper portions of your trapezius (i.e., trapezius I and II). By leaning forward (about 20-30 degrees), and then shrugging straight up -- not toward your ears, but vertically toward the ceiling -- you will activate trapezius III and IV. You may wish to support your upper body against a padded surface (like a preacher curl bench) in order to alleviate unnecessary stress on your lower back while leaning forward.
Fra dr.squat.com article: Exercise Technique
PW
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How to choose the right sized cuff for blood pressure measurement
The accurate measurement of blood pressure requires that the size of the cuff matches the size of the arm. If the cuff is not big enough, it will not compress the artery adequately, and a falsely high blood pressure reading will be obtained. If too big a cuff is used the pressure reading will be too low.
The way to find the right sized cuff is to measure the circumference of your upper arm at the level of the biceps muscle using a tape measure that reads in centimeters. The right cuff size should be chosen as shown in the table.
Arm circumference (centimeters)
Cuff type
Cuff size (centimeters)
Less than 33
Normal Adult
12 x 33
33-41
Large Adult
15 x 33
More than 41
Thigh
18 x 36
Home monitors normally come with a Normal Adult sized cuff, but you can usually order a large cuff
fra lifeclinic.com
PW
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Kære onkel Troels,
Jeg havde følgende oplevelse: Under hjerneugen fik jeg målt mit blodtryk ved en "stand". Resultatet var uventet højt, nemlig 150/90 (ca). Ved efterfølgende kontrol hos min egen læge, var resultatet 115/70.
Iflg. lægen kunne det høje resulatet ved den første måling skyldes en for lille manchet på den anvendte blodtryksmåler - og mit biceps-mål er beskedne 40 cm!!
Peter W
window of opportunity. Min diætist siger.....
in Vægttab
Posted
Før den udemærkede diætist udstyres med klaphat - kunne man så forestille sig at hendes ræsonnement var noget i
retnining af:
1. 'Hård træning' er dette tilfælde 10-12rm i de store basis øvelser med kort pause 45-60 sec. dette burde via den inducerde
mælke syre give en markant øgning af væksthormone (Kraemer) og derfor en øget fedtforbrænding.
2. Forhøjet væksthormon ses mindst 30min. efter endt træning.(Fry)
3. Intagelse af kulhydrate og/eller protein vil inducere et insulin response som sænke væksthormon niveauet.
4. Talsmænd for disse ideer er bla. Hatfield og DiPasquale og tildels Poliquin hvorimod Thibaudeau er mere skeptisk.
PW