Researchers found that breast cancer survivors who
took 12 weeks of yoga classes ended up with reduced inflammation and
felt less tired after six months, compared to a similar group of
women who didn't take yoga classes.
"This may be a way to provide a good activity that also has other
benefits," Janice Kiecolt-Glaser, the study's lead author, told
Kiecolt-Glaser is an investigator at The Ohio State University
Comprehensive Cancer Care Center and the Institute for Behavioral
Medicine Research in Columbus.
She and her colleagues write in the Journal of Clinical Oncology
that cancer survivors are twice as likely to have poor health and
more disability, compared to people without a history of cancer.
That may be partially explained by less exercise and activity during
and after cancer treatment, which may increase inflammation
throughout the body. Chronic inflammation has been tied to increased
risks for death and a number of health disorders.
Previous research has also found that inflammation tends to be
elevated among cancer survivors and people who don't do a lot
Yoga may be one way to get breast cancer survivors moving again,
because its intensity can be tailored to an individual's limits.
Yoga has also been linked to reduced fatigue among cancer survivors
through better sleep (see Reuters Health story of Aug. 30, 2013,
To see whether yoga had an effect on inflammation, mood and fatigue,
the researchers recruited 200 breast cancer survivors, who finished
their treatments at least two months before the study began in 2008.
The women were randomly assigned to one of two groups that either
participated in two weekly 90-minute yoga sessions for 12 weeks or
were put on a waiting list and told to avoid yoga.
The women's blood was analyzed for indications of inflammation. They
also answered a series of surveys and questionnaires to measure
their fatigue, vitality and mood.
At the end of 12 weeks, the researchers found that women taking the
yoga classes scored higher than the comparison group for vitality.
But there were no significant differences between the groups in
measurements of mood, fatigue or inflammation.
Another three months after the yoga classes ended, however, women in
the yoga group were less fatigued and had higher vitality scores
than women in the comparison group.
For example, before anyone did yoga, both groups of women scored
about 14 on a fatigue scale of 0 to 30, where higher scores indicate
greater fatigue. At the end of the study, the average score among
women in the yoga group was five, versus about 13 among women in the
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There was no difference between the groups in mood, but Kiecolt-Glaser
said the women weren't depressed enough at the start of the study to
leave room for improvement.
In addition to feeling less tired, the researchers found that at six
months the indicators of inflammation in the yoga participants'
blood samples were between 13 percent and 20 percent lower than
those in the comparison group.
"My best guess is that when women are sleeping better they're
less fatigued and their inflammation goes down," Kiecolt-Glaser
said, adding that the more often the women did yoga weekly, the
better their results.
While Kiecolt-Glaser said the women in the study would notice a
difference in their fatigue after the study, she added that it would
be difficult to know if the lower inflammation led to noticeable
differences. That would require longer studies.
Karen Mustian, who was not involved in the study but has researched
yoga among cancer survivors, said it's also important to find out
how yoga affects the body.
"We really need to be able to drill down and understand how it
works to be able to more accurately prescribe these interventions,"
said Mustian, who is from the James P. Wilmot Cancer Center at the
University of Rochester Medical Center in New York.
She also said yoga can be recommended to breast cancer survivors as
long as they're aware of some caveats, including that they should
pick a low-to-moderate intensity yoga, understand their physical
limitations and do their research to find a credentialed and trained
"Yoga is certainly an excellent intervention to try when women are
feeling fatigued post treatment," Kiecolt-Glaser said. "But in
general even for women and men who aren't cancer survivors, it may
be an excellent intervention if they're feeling fatigued and (have)
declined to take part in something more vigorous."
Journal of Clinical Oncology, online Jan. 27, 2014.
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