What is strength?
For the body, it means greater structural integrity and the ability to lift, pull and carry heavier loads. The body can be strengthened by putting it through certain stressors and giving it certain nutrients and rest periods. The body adapts to the physical stress it experiences (though there are limits to how much stress it can adapt to).
For the mind, strength can be loosely defined as any thought that allows you to overcome or solve a problem. The more we learn, the more problem solving tools we have. And there are different ways to learn. We learn from other people and we learn from direct experience.
Like the body, there are some stressors that can break the mind, rather than make it stronger. But the mind seems to be able to handle a lot more than the body. And there’s a strong link between the body and mind—stress to the body can help the mind go places it has never been before.
Get stronger, but don’t break.