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MNN.COM›Health› Fitness & Well-Being Medical myth or fact? Can cracking your knuckles lead to arthritis? Can jumping rope weaken your bones? Prevention magazine's Courtenay Smith debunks health-related tales. Read more: ENVIRONMENTAL SCIENCE, VIDEO CLOSE link: You might also like: Related Topics: Environmental Science, Video Related Videos News anchor bitten in face by dog on live TV Dog rescued from icy pond President cheers science students Time-lapse movies explore the natural world Comments Follow this conversation Add your comment View: All (0) Add your comment Sign in with one of these accounts or just add your comment below. Log in or create an account   Login Enter your comments E-mail: Used only for emailed comments and will not be displayed with your post Follow this conversation Notify me with an email when other people comment on this article. The posting of advertisement, profanity or personal attacks is prohibited. Click here to review our Terms of Use

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