How
Running Helps Your Muscles,
Which Helps Your Running
by Trevor Smith -
AmericanRunning.org
Contrast the chiseled contours of a
successful bodybuilder with the gaunt frame of an elite marathoner. Then
remember both can achieve stunning results by virtue of their muscles. An
amazing feature of your muscles is how much you can change them by training.
When you begin an aerobic training program, the capillary blood vessels in the
muscles you use begin to increase. You can end up with almost another 50%,
added to the capillary network you had before you began training.
Your muscles need enzymes to tell the power
houses (called mitochondria) in their cells how to carry out the biochemical
reactions that turn carbohydrate and fat into energy. The enzyme activity can
more than double with consistent training.
Part of the fuel your muscles use is right
there in the muscle fibers. This is a complex carbohydrate called glycogen. As
you train, your muscles' capacity for glycogen increases, so you can boost your
stored glycogen by eating more carbohydrates.
If you carbo-load by increasing your
carbohydrate calories to at least 70% of your total calories for at least three
days, you may be able to increase your muscles' glycogen store by more than
50%.
If you practice speedwork, or any
high-intensity efforts that put you into oxygen debt, your muscles produce more
lactate as a byproduct. This causes blood lactate to rise. The increase is
gentle at first, and then rises more sharply. This steeper increase in blood
lactate is called the lactate threshold.
Regular speedwork in your sport will raise
your lactate threshold. This means that your muscles can work harder to produce
only the same amount of lactate. This allows you to run (or ride, or ski, or
row ...) faster.
One of the most dramatic changes in
sedentary people as they grow older is their muscles grow smaller, accumulate
more fat, and become weaker. You can avoid the major part of these changes by
resistance training. Build up to eight to 12 repetitions of the heaviest load
you can handle, for each of your major muscle groups.
Two or three sessions a week are enough; you
even gain some benefits by working out only once a week, according to Michael
Pollock, Ph.D., and colleagues at the University of Florida in Gainesville.
Working out against high resistance (or
lifting heavy weights) causes microscopic damage in muscle fibers. During the
recovery period before the next workout, the fibers grow bigger and
stronger.
And it's never too late to benefit. Even
frail folks in their 90s increased muscle size by up to 10%, and strength as
much as doubled, according to Maria Fiatarone, M.D., and colleagues at Tufts
University in Boston.
Regular aerobic training and strength
workouts, proper diet and plenty of fluids will keep your athlete's muscles
young, no matter what the calendar says about your age.
Copyright,
The American Running
Association. |
