護膝-躺著訓練四頭肌

隨著年紀增長，最容易受傷的就是膝蓋，睡前透過這個簡單的運動增加自己骨四頭肌的力量，可以減少自己未來面前行動不便的問題。

As you get older, the most vulnerable is the knee. By simply increasing the strength of your quadriceps through this simple exercise before going to bed, you can reduce your inconvenience in the future.