Someone asked me the other day why I had five kids. My only conclusion is that I had somehow figured out how to handle four.
By default I am daily, sometimes hourly, invited to push myself to step up to the challenge. Mental and emotional survival has required me to become more organized, more patient, more balanced, more efficient, more humble. And really, these aren't bad things to be working on if my ultimate goal is to become a better person than I was yesterday.
Each time we exercise we apply this very same principle. We push our bodies beyond comfortable limits because we know that is the only way to get more fit than we were yesterday.
Don't resist when life offers you the ideal circumstances to grow and improve as a whole person. Most times it is the difficulties, life's "level 10s," that really stretch and mold us into the very people that when all is said and done, we most want to be!