Both those effects are tied to a lowered risk for heart disease or infections so it's possible walking might also help kidney patients stay healthier longer, although the trial was not designed to prove that.
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According to a team led by Joao Viana of Loughborough University in England, a weakened immune system raises a person's odds for infection while an overactive immune system results in chronic inflammation that damages blood vessels and boosts heart disease risk.
It's known that exercise can boost immunity and reduce inflammation, but there has been little research into these effects in kidney disease patients, the study authors noted.
Walking lowers inflammation
In the study, the British team had one group of patients with chronic kidney disease walk for 30 minutes a day, five times a week, for six months. They compared them to a "control group" of patients who did not increase their physical activity levels.
Walking seemed to increase the immune system's ability to fight infections while lowering inflammation, according to the study published online in the Journal of the American Society of Nephrology.
"Exercise exerts anti-inflammatory effects in patients with kidney disease and may in this way reduce their high risk for heart disease," Viana said in a news release from the American Society of Nephrology. On the other hand, he said, "our study also found no evidence that this level of exercise might be harmful to the immune system in people with kidney disease."
60 people worldwide have chronic kidney disease, the society said.
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