Do you think the nice kitty cares if you already went to the gym today?
Our ancestors used to walk for miles. Everyday. To hunt, gather, and hightail it out of harms way. It was good for us, in more ways than one.
So I'm befuddled when I hear people say, they've "already exercised for the day". What? Is another walk or bike ride gonna push them over the edge? I doubt most of us are going to "over exercise."
The difference between now and prehistoric times, is the sabertooth tiger could take you down instantly. Death by junk food just takes about 20, 30 years. Something to chew on. . .