Gabe Mirkin talks exercise
I am a bit of a fan of Dr Gabe Mirkin, he has great info on his blog and i used to run across his readio show but sadly I haven’t lately. Here are a couple of articles that he recently wrote that I have hung onto but wanted to post today.
Animal studies suggest that exercise may be even more important for older people than for younger ones. A report from the University of Illinois at Urbana-Champaign shows that exercise significantly decreased wound size and increased healing rate in older mice.
However, exercise had little effect on the rate of wound healing in young mice. (American Journal of Physiology – Regulatory, Integrative and Comparative Physiology, November 14, 2007).
Mice on Treadmills!
Mice ran on a treadmill at moderate intensity for 30 minutes a day for eight days. They then were given four full- thickness skin wounds and the rate of wound healing was checked daily for 10 days. Compared to age-matched non- exercising mice, the older exercisers healed faster.
The leading theory is that aging delays wound healing presumably because aging causes your body to produce more free radicals that damage the genetic material in cells.
After you eat, food travels into mitochondria, small areas in cells that turn food into energy. They do this by removing electrons and hydrogen from nutrients.
The electrons then attach to oxygen to form free radicals that stick to and damage the genetic material DNA in cells. This can delay healing and presumably even shorten life. Exercise causes the mitochondria to turn food into energy without producing as many free radicals, and therefore could hasten healing from any type of injury or illness.
Measuring Fat loss from exercise
If you weigh yourself before and after an hour or two of exercise, the difference is likely to be fluid loss. However, in events lasting several hours or even several days, measurable fat loss can occur.
At a competitive 12-hour indoor stationary bicycle marathon, one athlete took fluids and food throughout the entire competition, and still lost 2.64 pounds. Of this loss, 1.98 pounds was due to loss of fat. His calculated muscle increased by 1.46 pounds due to damage to the muscle cells, which results in fluid retention in the cells. Journal reference
During vigorous cycling, an athlete can burn between 600 and 1000 calories per hour, so this cyclist probably used more than 9000 calories in his 12-hour event. That is equal to the amount of energy needed to form almost three pounds of fat.
He lost only two pounds of fat because of the prodigious amount of food and drink he took in during the marathon. You can lose fat during a single exercise session, but you have to be in extremely good shape and exercise for a very long time to accomplish this.
For most exercisers, true weight loss will be measured over weeks or months.