Cheers, all,
Life is full of insurmountable opportunities - that's what Pogo said in his comic strip years ago. It was true then, and it's true now. I'm finding it more and more difficult to find the time to devote to this column, as new opportunities evolve in my work as an artist, as a standardized patient, and my growing family.
That said, I have to let this be my last column. It's been a true pleasure, writing Big Ideas for the past 8+ years. Thank you for giving me the experience. Big Ideas started with the Peninsula Track Club here in Newport News Virginia, and grew to have a readership in the US, Guam, Canada, and Italy. It's been great.
The best to you,
Sally Young
TIMING YOUR DINING
A calorie isn’t just a calorie when eaten at the wrong time of day. The timing of meals can greatly affect weight management recent studies with rodents have shown.
As nocturnal animals, most mice eat and explore at night, and sleep during the day, thanks to their internal biological clocks. But in new research, scientists disrupted this rhythm by introducing dim light during the active, dark cycle. The mice gradually shifted to eating during the day, when they should be resting, dumping calories into metabolisms that were set for sleep. These out-of-phase dinner bells resulted in mice that were heavier and fatter than the control mice that followed natures’ way. Both groups were matched for diet and activity.
The results are consistent with weight gain in human studies of “night-eating syndrome,” and with people who work night shifts. Although the mechanism may be related to body temperature, satiety hormones, and stress, Joseph Bass of Northwestern University found that a high fat diet alone had the same disruption of circadian rhythm in mice. "Maybe a very common perturbation, high-fat feeding, is one of the factors that disrupts the circadian rhythm," he says. "And disrupting the circadian rhythm, in turn, affects appetite.”
ANYWHERE BUT IN BETWEEN
Carl Foster, exercise scientist at University of Wisconsin - LaCrosse, took a clear-eyed view of how much time world-class runners spend in each training zone. Instead of thumbing through training logs and questionnaires, he measured the actual heart rates to determine the true exercise intensity and volume of practice sessions.
Intensity zones are based on physiological thresholds, which denote a change in the body’s response. Zone 1 is light intensity, below the ventilatory threshold, the point where breathing changes first occur; Zone 3 is the respiratory compensation threshold, where the lungs turn into rapid, stoking, air-sucking bellows; Zone 2 is the Goldilocks zone, the run that’s fun because it’s easy yet invigorating - but of marginal value to improvement.
Zone 2 is the place to stay you’re doing your best to have the non-experience of a lifetime, but tiptoeing across the rim of 80 percent and above your maximum heart rate will stress your body enough to make it adapt and become stronger. Although his study doesn’t account for cardiac drift that occurs after about 20 minutes of moderate running, Foster points out, “If you want to be you best, go hard and go easy, and don’t go in the middle.”
GARBAGE IN, GOLD MEDAL PERFORMANCE OUT LIFE IS SWEET
The “exercise in a pill” concoction that was headlined by the media in 2008 sounded like another pathetic charade to dupe a gullible public. Fitness and food, the sacred union of twin passions, are revered by athletes everywhere. But by 2009, the International Olympic Committee and World Anti-Doping Agency added AICAR - the exercise pill - to their lists of banned substances, and had tests ready to detect its use.
Ron Evans at the Salk Institute in California was originally investigating obesity, an inflection point in actuary tables where an extra thirty pounds turns insurance salesmen into prophets. Working with rodents, he stumbled upon a genetic switch known as PPAR-delta. Activating the switch upregulated the oxidation of body fat and the growth of mitochondria-rich slow-twitch muscles. His mice became remarkably fit without doing anything: they slimmed down, resisted weight gain even on a high fat diet, and could suddenly run long distances.
Evans and his team of scientists discovered that AICAR, a drug used in clinical trials for problems related to heart disease, could activate PPAR-delta. On high doses, sedentary mice suddenly became Marathon Mice, covering 44 percent farther distances than sedentary mice that didn’t take the drug.
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