Looking at my 2 T. hermanni tortoises I can really see their species having pushed themselves for the past 100 million years.

Sarcasm aside, what they're really doing when the sun is out in summer: Lying in the sunlight, eating, walking, eating, hiding under a bush, hiding under piece of wood, bathing, etc all the way until they're 80. Quite peaceful animals.

What matters not that you constantly push yourself... it's well-being and that you are in personal equilibrium. Anything else is probably gonna end in a crash some time.