Wednesday, January 7, 2015

Starting again: exercise

You are never too old to set another goal
or to dream a new dream.

- C. S. Lewis
The older I get the less I tend to make new year's resolutions. Still, upon entry into another year, I appreciate the opportunity to start again.

Healthy choices are always an area where I need to start again - the basic "eat less, exercise more" thing just isn't something I fall into easily. Rather, I  need to make intentions to choose to move more and munch less.

“Exercise is wonderful," said Louis. "I could sit and watch it all day.”
Larry Niven, Ringworld

This month's 1st Wednesday email offers gentle encouragement toward starting again in the area of exercise. Below you'll read a few studies that might dispel a myth or two and that just might give us a slight advantage in our exercise regimes.


Brief is good
This article on 2014 fitness trends relays that in a study from May, scientists found that three brief sessions per day of interval-style exercise — consisting of one minute of brisk walking followed by another minute of strolling, repeated six times — allowed people at risk of diabetes to control their blood sugar better than a continuous 30-minute walk. Importantly, these short “exercise snacks,” as the scientists called the condensed sessions, were more popular with the study’s participants than the single, longer walk, the scientists reported.


Warm is good
According to a surprising new study, exercising in chilly temperatures could undermine dieting willpower (as reported in this NYTimes wellness blog).
Researchers at the U of Aberdeen in Scotland and the U of Birmingham in England decided to see what happened to appetite when people exercised upright in alternately chilly and pleasant/neutral room temperatures.
   *study participants: 16 of overweight, sedentary men and women (small study).
   * baselines: resting metabolic rate, maximum endurance capacity, and blood levels of certain hormones related to appetite (ghrelin, PYY) were determined for each participant.
   * method: each participant walked on a treadmill at a moderate pace (at ~60 percent of each person’s maximum aerobic capacity) for 45 minutes.
During one workout the temperature of the room was 68 degrees; for the second workout, the room was cooled to 46 degrees (humidity was 40% for both).
After 45 minutes the volunteers were directed to help themselves at a large food buffet, unaware that their food selections and portions would be monitored.
   *findings: after walking in the cold (46 degrees), the volunteer study participants
 -  consumed significantly more calories and, in particular, more carbohydrates than when they had strolled in the more temperate room.
 - mostly showed higher blood levels of a hormone called ghrelin that is known to spark hunger. There was little change in ghrelin levels after the warmer exercise.

 - felt more ravenous and loaded their plates with more food than when they had been warm during their workout.  - expended significantly fewer calories during the exercise session in the cold than when walking while warm.
   * conclusions: warm temperatures demand more from the body, because it must dissipate any buildup of internal heat. Blood flows away from the stomach and limbs and toward the skin surface so that the excess heat can be released.
When exercising in cooler conditions, said Daniel Crabtree, a research fellow at the U of Aberdeen who led the study, “you don’t have to pump blood to the surface to dissipate heat.” The blood instead circulates normally, picking up and distributing biochemical signals from the stomach and elsewhere that apparently prompt the release of ghrelin, augmenting appetite and undercutting your best intentions to forgo that food treat after exercise.
Before bed is good
According to research published in Sleep Medicine, 52 young healthy adults who exercised vigorously (high-intensity cardio) before bedtime fell asleep faster and woke up fewer times during the night than those who did more mellow activities.

“If we could give every individual the right amount of nourishment and exercise, not too little and not too much, we would have found the safest way to health.” -Hippocrates

Just plain good
Also from this article on 2014 fitness trends: "other studies this year underscored how wide-ranging the benefits of exercise really are.
In various experiments, physical activity was found to
- lessen and even reverse the effects of aging on human skin;
- protect against age-related vision loss; improve creativity;
- lower people’s risk of developing heart disease even if they had multiple risk factors for the condition;
- increase the numbers of good bacteria in athletes’ guts;
- raise exercisers’ pain tolerance;
- alter, in desirable ways, how our DNA works; and
- keeps us young, according to a large-scale study published in October."

May you find motivation to move this month, and be well in body, mind, and heart.
 
“To resist the frigidity of old age, one must combine the body, the mind, and the heart. And to keep these in parallel vigor one must exercise, study, and love.”  Charles-Victor De Bonstettin