Friday, October 12, 2007

Cheap trainer shoes as good as (or better than) expensive ones

RUNNERS who buy expensive training shoes in the belief they are less likely to cause injury are deluding themselves, according to a new study. Researchers in Scotland tested running shoes, made by three manufacturers, that fell into three price bands - low (40-45 pounds or $90-$102), medium (60-65 pounds) and high (70-75 pounds).

After masking the manufacturer's logo and other tags with tape, the scientists slipped a thin pressure plate, shaped like an insole, into the shoes. The device, called a Pedar, measured the pressure at three points on the sole of the foot: under the heel, across the forefoot and under the big toe. The goal was to get an idea of the effectiveness of the cushioning that manufacturers add to the shoe to dampen the shockwave to the foot. Thus, the higher the pressure, the greater the force that is transmitted to the runner when his or her foot makes contact with the ground.

They then asked 43 young male volunteers to put on the shoes and walk along a 20m walkway in the lab. The volunteers each wore a small backpack which held a box that picked up data signals from the pressure gauge. Nine volunteers then wore the shoes as they ran on a treadmill, to see if this made any difference in sole pressures as compared to walking.

"Plantar pressure was lower overall in low- and medium-cost shoes than in high-cost shoes,'' says their paper, which appears in the British Journal of Sports Medicine. "This may suggest that less expensive running shoes not only provide as much protection from impact forces as expensive running shoes, but that in actual fact they may also provide more.''

The volunteers were also asked to assess the masked shoes for comfort. But their preferences were subjective and bore no relation to the distribution of plantar pressure or the cost of the shoe, the investigators found.

Running is a high-impact activity. With every footfall, a middle-distance runner experiences an impact equal to 2.5 times body weight - and this force increases with speed and fatigue. The impact transmits shock waves that are transmitted by the bones of the foot to the rest of the body, with the potential to cause knee damage, shin splints, muscle tears, Achilles tendonitis and other injuries.

Athletic footwear can reduce the impact by a third through good cushioning, as compared to the impact from walking barefoot, according to the study headed by Rami Abboud of the Institute of Motion Analysis Research at Ninewells Hospital and Medical School, Dundee.


More irresponsible statin evangelism

No mention of their often disastrous effect on quality of life -- which is WHY alleged "former" takers are focused on. It takes a lot for most people to continue with them. This is obviously such a careless study (see the rubrics and italics below) that I am not even going to bother looking at the abstract

People who take cholesterol-lowering drugs are protected from heart disease and premature death years after they stop taking them, a major study has shown. New research into statins - the world's biggest-selling medication - offers dramatic evidence of their long-lasting ability to halt and even reverse the progression of heart disease. The study, involving 6,500 men, found that those who took statins were still showing benefits of the drugs ten years after they had finished taking them. The chances of suffering a fatal heart attack over the period dropped by more than 25 per cent, the scientists found, while there was no evidence of unexpected side-effects. This remarkable result will increase pressure on GPs to prescribe statins to an even greater number of middle-aged people with raised cholesterol levels.

Professor Stuart Cobbe, of the University of Glasgow, the leading cardiologist on the study, said that he had been extremely surprised. "The benefit appeared to extend to at least ten years after the original trial," he said. The findings do not suggest that people on statins should give up; rather it is better to continue taking them. But even those who do give up continue to enjoy a benefit, Professor Cobbe said.

The results, published in The New England Journal of Medicine, come three months after a government adviser suggested statins should be offered to all men over 50 and women over 60 as an effective "shortcut" to prevent heart disease. Statins are currently taken daily by an estimated three million Britons to tackle high chloresterol. Heart disease is Britain's biggest killer, accounting for one in three deaths. The annual cost to the economy is about œ26 billion a year, the bulk of which is treatment costs.

Professor Chris Packard, a co-author of the study, said: "The impact of the statin treatment appeared to persist long after the active phase of the trial. This suggests that the drugs have lasting beneficial effects on the artery wall, possibly by stabilising plaques that might be about to rupture and cause an heart attack." Breakaway plaques can cause attacks by blocking the blood vessels and starving the heart of blood. Statins appear to stabilise the lining of the blood vessels, as well as damping down inflammation.

The original trial, the West of Scotland Coronary Prevention Study (Woscops), was launched between 1989 and 1991. More than 6,500 men aged between 45 and 64 who had not had a heart attack but had elevated cholesterol levels were recruited and divided into two groups. Half were given pravastatin and the other half a placebo. They were followed up for five years, until May 1995. The results showed that the risks of death from heart disease, or of suffering a heart attack, were significantly reduced in the statin users. The new study follows up the same men for another ten years. It compares heart attack and death rates in the original statin group against the original placebo group. Since the trial, both groups have changed. The statin group have tended to give up taking the tablets, while many of those in the placebo group have started to take them. No account was taken of these changes [Thus rendering the implications of the results completely indeterminate. Perhaps the group given a statin placebo have been so disillusioned by "their" statins that moved on to more harmful "natural" remedies], and a simple comparison was made of the 15-year experience of the original statin group against the original placbo group.

Professor Ian Ford, lead author of the study, said: "Remarkably, five years of treatment with a statin resulted in 27 per cent fewer nonfatal heart attacks or deaths due to heart disease over the period of 15 years. There was a significant 12 per cent reduction in deaths over the entire period, with deaths due to heart disease reduced by 22 per cent." The gap between the groups narrowed after the trial ended, and their use of statins tended to converge. But up to the end of the 15-year period, the original statin group did better than the original placebo group, showing a persistence of the effect. [Or showing that most high-risk people end up taking statins for a while; some sooner, some later. And maybe those given it when younger tend to tolerate it better. It is all pure speculation]

Professor Ford said: "The results of the follow-up provide strong support for the safety of five years of statin use. "When fatal and nonfatal heart disease events were studied it was found that, despite the fact that most of the participants were not treated with a statin after the first five years of the trial, there was evidence of the group originally receiving the statin continuing to be at lower risk of having a heart disease event."

Statin prescriptions have risen by 150 per cent in England in the past five years. The trial raises the question of whether they should be given to an even wider group, including younger people in whom heart disease has yet to get a start.



Just some problems with the "Obesity" war:

1). It tries to impose behavior change on everybody -- when most of those targeted are not obese and hence have no reason to change their behaviour. It is a form of punishing the innocent and the guilty alike. (It is also typical of Leftist thinking: Scorning the individual and capable of dealing with large groups only).

2). The longevity research all leads to the conclusion that it is people of MIDDLING weight who live longest -- not slim people. So the "epidemic" of obesity is in fact largely an "epidemic" of living longer.

3). It is total calorie intake that makes you fat -- not where you get your calories. Policies that attack only the source of the calories (e.g. "junk food") without addressing total calorie intake are hence pissing into the wind. People involuntarily deprived of their preferred calorie intake from one source are highly likely to seek and find their calories elsewhere.

4). So-called junk food is perfectly nutritious. A big Mac meal comprises meat, bread, salad and potatoes -- which is a mainstream Western diet. If that is bad then we are all in big trouble.

5). Food warriors demonize salt and fat. But we need a daily salt intake to counter salt-loss through perspiration and the research shows that people on salt-restricted diets die SOONER. And Eskimos eat huge amounts of fat with no apparent ill-effects. And the average home-cooked roast dinner has LOTS of fat. Will we ban roast dinners?

6). The foods restricted are often no more calorific than those permitted -- such as milk and fruit-juice drinks.

7). Tendency to weight is mostly genetic and is therefore not readily susceptible to voluntary behaviour change.

8). And when are we going to ban cheese? Cheese is a concentrated calorie bomb and has lots of that wicked animal fat in it too. Wouldn't we all be better off without it? And what about butter and margarine? They are just about pure fat. Surely they should be treated as contraband in kids' lunchboxes! [/sarcasm].

Trans fats:

For one summary of the weak science behind the "trans-fat" hysteria, see here. Trans fats have only a temporary effect on blood chemistry and the evidence of lasting harm from them is dubious. By taking extreme groups in trans fats intake, some weak association with coronary heart disease has at times been shown in some sub-populations but extreme group studies are inherently at risk of confounding with other factors and are intrinsically of little interest to the average person.


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