Too Much or Too Little Activity Can Spur Knee Problems11/26/12
MONDAY, Nov. 26 (HealthDay News) -- For middle-aged adults
trying to protect their knee health, it may be best to avoid
extreme ends of the exercise spectrum, such as too much high-impact
exercise or too little physical activity, researchers have
While playing tennis and running can speed up the deterioration
of knee cartilage, so can just sitting on the couch, investigators
from the University of California, San Francisco, pointed out.
Using MRI scans, the researchers monitored changes in the right
knee cartilage of 205 patients over the course of four years.
Cartilage at the patella, femur and tibia of the right knee joint
were examined when the study began, at a two-year visit and again
after four years.
The participants, who ranged in age from 45 to 60 years, also
kept track of their physical activity in a questionnaire. Some of
the participants involved in the study also wore an accelerometer,
a device used to record physical activity.
The study was scheduled for presentation Monday at the annual
meeting of the Radiological Society of North America, in
"In this study, we used the subjective measure of a questionnaire," Dr. Thomas Link, a professor of radiology and chief of musculoskeletal imaging at UCSF, said in a society news release. "The accelerometers provide a more objective way to measure physical activity."
The study found high-impact physical activity is associated with
greater cartilage deterioration and increased risk for
osteoarthritis. The participants who were the most active had an
accelerated "T2 relaxation time." But the same was true for those
with very low levels of activity, the investigators found.
The study authors concluded that there may be an ideal amount of
physical activity that people should get that will protect their
knee cartilage, and cartilage measurements could allow doctors to
detect changes at an earlier stage when they could still be
"Lower-impact sports, such as walking or swimming, are likely more beneficial than higher-impact sports, such as running or tennis, in individuals at risk for osteoarthritis," Link pointed out in the news release.
About half of people in the United States could develop knee
osteoarthritis by the time they are 85 years old, according to the
U.S. Centers for Disease Control and Prevention. They estimate that
about 67 million American adults will have physician-diagnosed
arthritis by 2030.
The data and conclusions of research presented at medical
meetings should be viewed as preliminary until published in a
While the study found an association between activity levels and
knee problems, it did not prove a cause-and-effect
The American Academy of Orthopaedic Surgeons has more about
Copyright © 2012
. All rights reserved.
Please be aware that this information is provided to supplement the care provided by your physician. It is neither intended nor implied to be a substitute for professional medical advice. CALL YOUR HEALTHCARE PROVIDER IMMEDIATELY IF YOU THINK YOU MAY HAVE A MEDICAL EMERGENCY. Always seek the advice of your physician or other qualified health provider prior to starting any new treatment or with any questions you may have regarding a medical condition.