Relaxed muscles means[1] less tension, which means less pain.

肌肉放松意味着紧张度减少，疼痛减少。

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Snoring is caused by a few things, but the biggest culprit is a vibration of very relaxed muscles and tissues in the throat, which rattle against narrow breathing passages.

打呼是有几方面的因素造成的，但是罪魁祸首是喉管内过份松弛的肌肉和组织，在狭窄的呼吸道内发出声响。

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The massage relaxed my tense back muscles.

按摩使得我背部紧张的肌肉松弛下来。

《牛津词典》

They are then given physiotherapy so they can learn how to keep their muscles relaxed using exercises such as stretching.

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Jaeger's basic philosophy was this: Extending the elbow and shoulder muscles in a relaxed, fluid motion prepares an arm to throw as hard as it can.

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