A triathlon is a race comprised of three back-to-back endurance sports, typically swimming, cycling, and running. If it happened to be comprised of three events such as sleeping, eating, and mowing the yard, then everyone would do it and we’d call it just be another day in the life. Instead, it’s probably the most difficult thing that anyone will do in life. Want to see how far you can push yourself? Put the mower away and start running instead.