Can exercise detoxify the body? Health experts are skeptical

* Yoga advocates say moves improve circulation, aid detox

* Others say liver and kidneys detoxify the body

NEW YORK, Dec 17 (Reuters) - The word "detoxification" is

flung around the fitness community as frequently as kettlebells

are swung.

Yoga teachers regularly speak of detoxifying twists,

aerobics instructors of detoxifying sweat, dieters of

detoxifying fasts. But health professionals are skeptical.

"If you start talking about exercising to detoxify, there's

no scientific data," said Dr. Elizabeth Matzkin, chief of

women's sports medicine at Harvard Medical School. "The human

body is designed to get rid of what we don't need."

The same applies to fasting.

"No good scientific data supports any of those cleanses,

where you drink juice, or (only) water for a week," she said.

Exercise is important, Matzkin added, because it enables our

body to do what it is made to do, but the kidneys and colon get

rid of waste. The role of exercise in that process is unclear.

"In general exercise helps our lungs; kidneys get rid of

things that can cause us onset of disease," she said.

A healthy lifestyle - eating healthy, drinking plenty of

water and exercising - is important to detoxifying because it

enables our body to do what is intended to do.

"As for specific yoga moves, I'm not so sure," she said.

Yoga instructor and fitness expert Shirley Archer, an author

and spokeswoman for the American Council on Exercise (ACE) said

the theory behind the effectiveness of detoxifying twists in

yoga is that they squeeze the organs, which push the blood out

so fresh blood can rush in.

"Better circulation equals better health," said Archer, who

is based in Florida. "If detox means to eliminate from the body

what it no longer needs, then certain yogic practices can help."

She said yogic deep breathing with strong exhalations

can empty the lungs of unneeded carbon dioxide and allow for a

fresh breath of more oxygenated air. "This nourishes all of our

cells," she said. "It is also a method of cleansing because

better circulation equals better health."

Meditative movement practices, such as yoga and tai chi, she

added, can detox your attitude because they require staying in

the present moment and discourage dwelling on the past.

Last summer, celebrity trainer Tracy Anderson began taking

groups of 40-odd women on what she calls Detox Weeks, which

involve at least three hours of workouts each day, as well as

lectures on fitness and nutrition aimed mainly at encouraging

lifestyle changes.

Similar weeks in other cities are planned for 2013.

"Women work out and think 'Why can't my love handles, muffin

tops go away'?" said Anderson, creator of the Tracy Anderson

Method and a co-owner, with actress Gwyneth Paltrow, of fitness

centers in Los Angeles and New York. "The most important thing

is if you can become a consistent exerciser."

"A good workout is not five to 10 yoga poses," she

explained. "You have to learn to scale up your endurance. If you

can only jump for five minutes straight, we'll go to 10 minutes,

then 20 minutes."

Anderson said she uses the term detoxification broadly to

include everything from working up a good sweat to clearing the

mind of destructive thoughts.

"Detoxification is a big topic," she said.

Nancy Clark, a registered dietitian in Boston, Massachusetts

and a member of the American College of Sports Medicine, said

the body generally does a fine job of detoxifying itself through

the liver and kidneys. Sweating has nothing to do with it.

"When you sweat you really don't detoxify anything," she

explained. "If someone goes on a crash diet, then maybe toxins

are released but then the body would take care of them. When you

sweat you lose sodium."

(Editing by Patricia Reaney and Todd Eastham)

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