Why do I feel better after I’ve cracked my neck?

It is thought that one of the most common causes of neck ‘cracking’ is gas bubbles in the synovial fluid escaping a tight space. Thissynovial fluidis a lubricant between the joints, formed by a combination of carbon dioxide, nitrogen and oxygen.

If you deliberately roll your neck, it is thought that you can sometimes release these bubbles, resulting in a series of popping sounds that may sound like cracking. The release of the gas build-up explains why muscles or joints often feel looser and more comfortable after they’ve been ‘popped’ or‘cracked’.

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Asked by: K艾文哈丁,贝德福德

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