Why strive? Unless you are a masochist, or obligated to a sadist, you need to understand why you habitually compete, train, perform, rehearse, withdraw, study, read, write, paint, lift weights, golf, run, swim, diet or engage in physically and mentally strenuous activities.
Maybe you do it to relieve physical exuberance, social sensation or to ease status anxiety.
You could also do it simply for the joy of it.
Joy manifests happiness, which according to Aristotle, is the Chief Good. There are 4 kinds of Happiness recognised by the Happiness Alliance: hedonism, eudaimonia, spiritualism and flow. I believe Extreme Flow is optimal achievement that dilates time.
Extreme Flow is joyful accomplishment by focussing on a personal goal with full and skilful mental engagement. It is not meditation or mindfulness. Nor does it nurture you to seek external rewards. The joy comes in achieving continuously, striding over hurdles like a succession of sub-goals that are part of achieving the overall goal of a personal best. It is joy you can have training and performing. It is joy that takes your mind off the pain in your body. Your mind has to be totally committed to your every stride.
My futuristic novel Time is Gold tells the story of Maxi, who trains using Extreme Flow to break the world marathon record, coached by experts. It is available from Amazon.