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http://www.kshb.com/kshb/sports/article/0,1925,KSHB_9430_3540889,00.html
Studies: Vitamin E, protein especially valuable to runners
By JOE ROMINIECKI
Scripps Howard News Service
12-FEB-05
While veteran runners and ambitious joggers toil through
the winter months as they prepare for the spring marathon
season, two recent studies suggest that vitamin E and protein
can bolster the body's health during times of demanding
exercise.
Researchers in Oregon examined the benefits of vitamin
E supplements for runners in a 50-kilometer (31 mile) ultramarathon
in Corvallis. Their study found that runners taking vitamin
E did not experience the usual increase in lipid oxidation
_ a kind of damage that can weaken cells and cause long-term
cardiovascular problems _ that results from extreme exercise.
"We looked at a marker of oxidative damage,"
said Dr. Maret Traber, principal investigator at the Linus
Pauling Institute at Oregon State University. Traber helped
conduct the study, published in May in the medical journal
Free Radical Biology.
"It's called isoprostane, and isoprostanes are important
because they're associated with an increased risk of heart
disease. So we were really interested. Could we protect
the runners?" she asked.
The answer was yes.
Traber said a daily dose of 400 international units of
vitamin E protects endurance athletes from damage that is
linked to a number of long-range health problems, including
diabetes, stroke, heart disease and Alzheimer's. She stressed,
however, that a vitamin E supplement is necessary because
the amount found in a regular diet isn't enough.
(A study published Jan. 4 in the Annals of Internal Medicine
suggested that high doses of vitamin E may slightly raise
overall mortality. The study examined 19 clinical trials
involving more than 130,000 participants, and some critics
said they were not persuaded because of the difficulty in
combining results from several studies.)
Meanwhile, another study shows that protein consumption
after exercise can help to maintain the body's short-term
health during intense training periods.
Researchers at Iowa State University studied Marines during
their 54-day basic training. A third of the recruits received
a protein supplement after workout sessions, while the rest
received a carbohydrate supplement or a placebo. The protein
group experienced fewer infections, fewer treatments for
muscle soreness and far less heat exhaustion than the others.
While protein has been known to help rebuild muscles after
physical stress, the results of the study extend beyond
that, said Paul Flakoll, a professor of nutrition at Iowa
State who published the study in the Journal of Applied
Physiology in March.
"People training at that level _ marathoners are a
good example _ a lot of times have compromised immune function,"
he said. "There's been a lot of work with antioxidants
in marathon runners, but it looks like protein may be very
important for that as well."
Flakoll emphasized protein should be consumed immediately
after exercise, but he said that an appropriate amount can
be found in protein milkshakes or bars or in protein-rich
food. A pill isn't necessary.
That approach may please marathoner Deena Kastor, 31. The
2004 Olympic bronze-medalist said nutrition is essential
to her success, but she doesn't get wrapped up in the multitude
of "gimmick" supplements or diets that continually
appear on the market.
"I believe that you can get all the nutrition you
need through food that you eat, so I don't believe in supplementation
at all," Kastor said. "I definitely try to get
a combination of proteins and carbohydrates within a half
hour of running, but I'd rather get it though eating some
leftover steak from the night before and throwing it into
some pasta."
Food or pills, or both, is an athlete's decision, but any
runner preparing for a marathon should monitor nutrition
as meticulously as training, Traber said.
"There's a lot of enthusiasm for extreme exercise.
Yes, do the extreme exercise, but protect yourself."
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