I like this anecdote from Derek Sivers* about effort, stress, and the importance of relaxation while working:
A few years ago, I lived in Santa Monica, California, right on the beach.
There’s a great bike path that goes along the ocean for 7½ miles. So, 15 miles round trip.
On weekday afternoons, it’s almost empty. It’s perfect for going full-speed.
So a few times a week, I’d get on my bike and go as fast as I could for the 15 mile loop. I mean really full-on, 100%, head-down, red-faced, sprinting.
I’d finish exhausted, and look at the time. 43 minutes. Every time. Maybe a minute more on a really windy day. But basically always 43 minutes.
After a few months, I noticed I was getting less enthusiastic about this bike ride. I think had mentally linked it with being completely exhausted.
So one day I decided I would do the same ride, but just chill. Take it easy, nice and slow. OK not super-slow, but dialing it back to about 50% of my usual effort.
Give it a read.