Taking a bigger picture: Muscle atrophy is one of the biggest causes of reduced quality of life in the elderly (and also the not so elderly). Women in particular are susceptible to this due to their smaller amount of muscle mass to begin with and the general cultural aversion to women undertaking resistance exercise. My own experience (as a man and admitted gym rat) is that resistance training sorts out my back probl…
I spent years under the misconception that being skinny (but not scrawny) meant I was fit. It wasn't until I started a proper weight/interval training routine that a) I realized how out of shape I was and b) my lower back stopped being so damned fragile.