That's just one tool to avoid strain and it's not for everyone.
The important thing is to remember that strain creeps up on you slowly, then hits hard. You can get away with bad habits for years, but left unchecked one day you'll find you can't do anything, it all hurts too much.
Don't push yourself. If you find yourself aching a little, address the problem rather than pushing through it. I know several people that were knocked out of commission for the better part of a year after a few decades of casual neglect.
