Why Strength training is a must for Everyone?

What's so Important About Core Strength?
There is way more to core training than the abdominals( and getting a flat tummy). Core training does two really important things, It helps you look thinner, and it supports your spine and helps with things like balance. I noticed when I started doing Focus T25 and Piyo that the core muscles are connected to your legs, to the way you stand, squat and sit. It's not just about the abdominal muscles, but also training your back, your glutes, and the entire area that connects to your spinal cord and helps your body support your spine, so that the  burden of supporting your body weight isn't just placed on your bones. Those deep muscles of the core are the ones that do all the good stuff, like support your spine and act as a natural corset, so when you work them not only do you get a flatter stomach but a tighter stomach.
http://www.sparkpeople.com/resource/fitness_articles.asp?id=364