Jerry, in the interest of stalling for recovery time during Warrior Bootcamp, shared a joke with us a couple of weeks ago. As it turns out, it is relevant to today's blog. So a scientist wanted to see if a frog could jump without legs. He cut one leg off and yelled "Jump!". The frog jumped. Excited by the result, he cut the remaining three legs off the frog and yelled "Jump!". Disappointingly, the frog did not move. The scientist's obvious conclusion was that cutting off all the frog's legs rendered it deaf.
With our ever-increasing access to technology at our fingertips it seems that we are continually bombarded with the latest and greatest health and fitness news, much of which is contradictory. So how do we know what to believe? The answer is very little.
Dr. John Ioannidis, University of Ioannina School of Medicine, Ioannina, Greece, and Institute for Clinical Research and Health Policy Studies, Department of Medicine, Tufts-New England Medical Center published a paper in the online journal PLoS Medicine, which is committed to running any methodologically sound article without regard to how “interesting” the results may be. David Freedman of The Atlantic summarized his paper as follows: In the paper, Ioannidis laid out a detailed mathematical proof that, assuming modest levels of researcher bias, typically imperfect research techniques, and the well-known tendency to focus on exciting rather than highly plausible theories, researchers will come up with wrong findings most of the time. Simply put, if you’re attracted to ideas that have a good chance of being wrong, and if you’re motivated to prove them right, and if you have a little wiggle room in how you assemble the evidence, you’ll probably succeed in proving wrong theories right. His model predicted, in different fields of medical research, rates of wrongness roughly corresponding to the observed rates at which findings were later convincingly refuted: 80 percent of non-randomized studies (by far the most common type) turn out to be wrong, as do 25 percent of supposedly gold-standard randomized trials, and as much as 10 percent of the platinum-standard large randomized trials. The article spelled out his belief that researchers were frequently manipulating data analyses, chasing career-advancing findings rather than good science, and even using the peer-review process—in which journals ask researchers to help decide which studies to publish—to suppress opposing views. “You can question some of the details of John’s calculations, but it’s hard to argue that the essential ideas aren’t absolutely correct,” says Doug Altman, an Oxford University researcher who directs the Centre for Statistics in Medicine.
Following are a few examples of common misconceptions that originated from old wives tales or faulty studies, and have since been proven wrong.
Following are a few examples of common misconceptions that originated from old wives tales or faulty studies, and have since been proven wrong.
You lose most of your body heat through your head.
False! The amount of heat released, or lost, by any part of the body is determined primarily by its surface area. You lose more heat through an exposed leg or arm than a bare head.
False! The amount of heat released, or lost, by any part of the body is determined primarily by its surface area. You lose more heat through an exposed leg or arm than a bare head.
Perform static stretches before exercise to warm up and improve performance.
False! Studies now show that static stretching before a run can result in a 5 percent reduction of efficiency. Research also shows that static stretching has an acute weakening effect on weight lifters.
Cholesterol in eggs is bad for the heart.
False! The perceived association between dietary cholesterol and risk for coronary heart disease stems from dietary recommendations proposed in the 1960s that had little scientific evidence, other than the known association between saturated fat and cholesterol and animal studies where cholesterol was fed in amounts far exceeding normal intakes. Since then, study after study has found that dietary cholesterol (the cholesterol found in food) does not negatively raise your body’s cholesterol.
Never let your knees go past your toes when you squat.
False! This incorrect conclusion was drawn when a 1978 study at Duke University found that keeping the lower leg as vertical as possible during the squat reduced shearing forces on the knee. However, in truth, leaning forward too much is more likely to cause injury. In 2003, University of Memphis researchers confirmed that knee stress was 28 percent higher when the knees were allowed to move past the toes during the squat. But the researchers also found a counter effect: Hip stress increased nearly 1,000 percent when forward movement of the knee was restricted. The reason: The squatters had to lean their torsos farther forward. And that's a problem, because forces that act on the hip are transferred to the lower back, a more frequent site of injury than the knees.
Thus the new recommendation is to focus more on your upper body and less on knee position. Try to keep your torso as upright as possible as you perform squats (and lunges), and you'll reduce the stress on your hips and back (i.e. look at Katie).
False! Studies now show that static stretching before a run can result in a 5 percent reduction of efficiency. Research also shows that static stretching has an acute weakening effect on weight lifters.
Cholesterol in eggs is bad for the heart.
False! The perceived association between dietary cholesterol and risk for coronary heart disease stems from dietary recommendations proposed in the 1960s that had little scientific evidence, other than the known association between saturated fat and cholesterol and animal studies where cholesterol was fed in amounts far exceeding normal intakes. Since then, study after study has found that dietary cholesterol (the cholesterol found in food) does not negatively raise your body’s cholesterol.
Never let your knees go past your toes when you squat.
False! This incorrect conclusion was drawn when a 1978 study at Duke University found that keeping the lower leg as vertical as possible during the squat reduced shearing forces on the knee. However, in truth, leaning forward too much is more likely to cause injury. In 2003, University of Memphis researchers confirmed that knee stress was 28 percent higher when the knees were allowed to move past the toes during the squat. But the researchers also found a counter effect: Hip stress increased nearly 1,000 percent when forward movement of the knee was restricted. The reason: The squatters had to lean their torsos farther forward. And that's a problem, because forces that act on the hip are transferred to the lower back, a more frequent site of injury than the knees.
Thus the new recommendation is to focus more on your upper body and less on knee position. Try to keep your torso as upright as possible as you perform squats (and lunges), and you'll reduce the stress on your hips and back (i.e. look at Katie).
Now for the million dollar question which I'm sure some of you have already asked yourselves as you are reading this, "Are any of the above studies going to be proven wrong in the future?". Perhaps. The one sure thing that we have learned in our years of training and reviewing research is that things are always changing and what we don't know far outweighs what we do know. What we do like about one of our primary sources for information regarding metabolic training and fitness is that they don't jump at the latest fitness fad, but instead base their training methods on studies that are based on the most sound research and have been replicated a number of times. They are also not afraid to change course based on newer findings.
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