Unexhausted has been my virtue

Through the trials and tribulations, the highs and smiles of life, one has to keep going. Maintaining that even keel in storms and calm seas. A paradox, a puzzle. And throughout, you have to have energy to keep the journey going. Your stores have be deep, and they have to be replenished over a period of time. Life is a marathon, and unexhausted has to be your virtue.