Saturday, April 05, 2008


Apparently it is no better than other forms of exercise as far as hardening of the arteries is concerned. But sedentary people have more hardening. The study below is extremely limited, however. It relies on self-report, the sample size was small and included obvious but unknown selection biases and the groups were also nutritionally different. I don't think I would have mentioned it except that it was reported in "The Times" of London. It actually proves nothing. Abstract below:

The influence of physical activity and yoga on central arterial stiffness

By Courtney M Duren

Purpose: Central arterial stiffness is an accepted risk factor for cardiovascular disease. While aerobic activity is associated with reduced stiffness the influence of practicing yoga is unknown. The aims of this study were to: 1) evaluate arterial stiffness in middle-aged adults who regularly practiced yoga, performed regular exercise, or were inactive, 2) evaluate the reproducibility of arterial stiffness measured in the left and right carotid artery and by pulse wave velocity (PWV).

Methods: Twenty six healthy subjects (male and female, 40-65 yrs old) were tested on two separate days. Carotid artery distensibility (DC) was measured with ultrasound. Physical activity was determined by questionnaire.

Results: Yoga and aerobic subjects had similar physical activity levels. Yoga and aerobic groups were not different in either DC (p = 0.26) or PWV (p = 0.21). The sedentary group had lower DC and higher PWV compared to the aerobic and yoga groups (both, p < 0.001). Stiffness measures were reliable day to day (coefficients of variation ~2.5%) and similar between left and right arteries (CV = 2.2%).

Conclusion: Physical activity was a strong predictor of both measures of arterial stiffness, although other factors such as nutritional status need to be accounted for. An independent effect of practicing yoga could not be detected. Stiffness measures were reproducible and left and right sides were consistent with each other.



Should you be more scared of hoodies or terrorists? Ought global warming make us shiver more than the Cold War? Welcome to the apocalypse auction, where experts and authorities bid up their pet threats to public safety. In competing to win headlines, they all seem to lose a sense of perspective.

Sir Ian Blair, Metropolitan Police chief, now claims that "youth violence" is the greatest "threat to the whole of London, perhaps with the exception of terrorism". Only "perhaps"? After all, Sir Ian has previously said that Islamic terrorism poses a threat to London "far graver" than the Second World War. Prime Minister Gordon Brown prefers to compare terrorism today to the Cold War. Are we to conclude that the hoodies now present "perhaps" as big a threat to our society as the Luftwaffe or the Red Army?

But hold your four horsemen of the apocalypse a minute. An army of experts led by Sir David King, until recently the chief government scientist, has declared global warming an even bigger threat than terrorism. Should we focus all our fears on that instead? Then again, that might underestimate the threat of the enemy within our waistbands, since the Health Secretary, Alan Johnson, has pronounced obesity "a potential crisis on the scale of climate change".

To recap the bids. Youth violence is perhaps as big a threat as terrorism, which is a far graver threat than the Nazis, but not as hot as global warming, which is the same size threat as obesity. We await news of more new little Hitlers and Stalins lurking out there.

What purpose is served by this apocalypse auction? Who does it help to compare the tragic killing of 11 London teenagers this year with a terrorist threat? Come to that, how can it further our understanding of Islamic terrorism - which killed 52 people in London in 2005 - to claim that it is more serious than the wartime Blitz that left 43,000 Londoners dead?

And how complex issues such as climate change and obesity might be clarified by overheated, fat-headed comparisons is anybody's guess.

As they compete to make a media impact, experts raise the scaremongering stakes ever higher. New research even claims that mobile phones are "more dangerous than smoking". (Maybe they'll ban mobiles in public...) The likely results of this my-risk's-bigger- than-yours talk will be to raise public anxieties further - and lower public trust in anything that officials say.

These comparisons are not only odious, but dangerous. In fact, it is surely no exaggeration to suggest that the apocalypse auction might pose a bigger threat to rational discussion than, er, anything else that ever happened before.


Food Fascism hits New Zealand kids

Children in a New Zealand school have been banned from bringing cakes to share on their birthdays, due to new government healthy eating guidelines. Pupils at Oteha Valley primary school north of Auckland have been told they are allowed to celebrate their birthdays, but the cake must stay at home, the New Zealand Herald newspaper reported. The Ministry of Education has been on a fat-busting crusade, introducing sweeping guidelines against unhealthy food in New Zealand schools.

Oteha Valley has a large number of pupils born in September and October, and there can be up to four cakes a week in some classes, principal Megan Bowden told the paper. It had come to the point where parents thought they were required to provide a cake for their child's birthday. The school has advised parents in a newsletter to stop sending cakes to school from the next term.

A Ministry of Education spokesman told the newspaper the government guidelines only applied to food sold on the premises, and schools did not need to monitor food brought in from outside.


1 comment:

Anonymous said...


Yoga does not improve everyday body language like a related technique does, it being based on practical anatomy instead of Chakaras and chanting in unknown languages etc.:

The Alexander Technique

It does initially uncomfortable stretching, just like yoga, while not just breathing, but LOUDLY VOCALIZING UP AND DOWN THE MUSICAL SCALE, and overall teaches one how to use one's spine to support the upper body (especially the very top few vertebrae that merge with the skull) and to stop locking one's knees while standing or walking, too. This training strongly pushes study of ACTUAL physical anatomy, including the natural posture young children and wild animals was invented by an actor who kept losing his voice, so it was developed as a practical method, and unlike yoga, is now a standard part of voice lessons for all singers and actors, worldwide.

For instance, to use a computer keyboard, you no longer support your torso with your palms but allow your fingers to be held up in the air by your muscles, as you sit on your sitting bones instead of your thighs.

That upright instead of submissive body language affects mood positively. That mood affects health is not exactly proven in but in a few large studies (Harvard nuns study is one), but the ONLY way to get a good voice, meaning to get social attention and thus raise your social status in the process, is to learn to use your spine (only) to support your frame, so that, exactly like a cello, the relaxed and thus elastic "sound box" of your lungs and belly (even down to your feet, I kid you not!), can RESONATE with the voice, as can the facial muscles (a detailed form of Alexander Technique called Feldenkrais Technique involves a whole season of learning to relax your facial muscles, especially the jaw and tongue).

But yoga does none of this. Alexander Technique classes are fun and interactive, but yoga class teachers inject weird chants and New Age music. They do not offer any actual mind/body alterations.

I even had to get my glasses prescription changed, since I was squinting one eye to make it see better, but got dizzy spells when those fanatically patient teachers spotted the tension and took it away. One eye ended up needing less correction, and the other a bit more. But this made my "dominant eye" less clear than the other one (much like right/left handedness, one eye determines where we see things, the other just adding 3D detail). Drove me nuts (!), especially since it changed from bright day to night, as a larger iris at night made one eye much more blurry, but I digress.

Another digression is that the point is to learn to let go of conscious control of your posture and movements. Especially, in this day and age, the conscious sucking in of one's tummy in order to not look "so fat". Yet the spine being more erect mostly compensates for this anyway.

My point is that yoga may have little effect on heart disease since it is for the vast majority (vs. a small minority of very advanced class members), it is not even aerobic, so can't even count as "exercise". Nor, more importantly, does it provide periodic extreme physiological stress followed by rest periods, unless you count muscle stretching as "stress". My direct observation is that the VAST majority of yoga class members are overweight females (80% fat vs 10% are obviously ballet dancers) or utterly emancipated vegetarian males (10%) most of who cannot do basic "fraternity party trick" type of moves such as a simple hand-stand, even against a wall.

I will also mention that yoga classes are basically no fun. There is an air of high seriousness involved, and a sense of spoiled, fragile people who are using yoga to become "spiritual" who are soothed about how stressful things like arriving to class on time or boxes spilling out of their closets (happened to one instructor as the worst stress she had that week!). There is also the fact that there is no reason at all to do yoga in a group, since unlike Alexander classes, interaction is actively discouraged by the militant teachers. I once got tired, having accidentally taken an advanced class, so sat against the wall for a minute or two, but my minute was cut short by being screamed at to adopt the "down doggie" position, lest others worry I might be "looking at them" (which is how you learn what "down doggie" means, though in this case, you can imagine how similar it is to Muslim praying).

I'd translate the headline to: "New Age fossile-hippie gatherings that include ritual obedience to a guru-like guide who plays weird bell-dinging music do not prevent heart disease because it fails to provide any actual cycling between tension and relaxation, but merely piles tension upon tension and supresses any and all expression of individuality."