They are known as "second generation" drugs, designed to alleviate side effects of older "first generation" medicines that often caused muscle spasms and stiffness.

VOA: standard.2010.07.08

One by one he subdued his father's trees By riding them down over and over again Until he took the stiffness out of them - And not one but hung limp, not one was left for him to conquer.

他一株一株地征服他父亲的树,一次又一次地把它们骑在胯下,直到把树的倔强劲儿完全制服：,一株又一株都垂头丧气地低下来。

耶鲁公开课 - 现代诗歌课程节选

Ellen Brown says the exercises help relieve her pain and stiffness from arthritis.

VOA: standard.2010.02.26