Happiness Bar
From The Blockheads Wiki
Your happiness meter shows how happy your blockhead is according to his food, environment, energy, and health meter. When your happiness meter lowers so does the speed of your blockhead. If you keep your happiness meter at max your blockhead will be able to run faster, craft quicker, and mine faster. No matter what happens your happiness meter will not be higher than your health meter, so if you wonder why all your meters are at max except happiness, you might want to check to see if you overlooked your health meter, if you did just eat food and you will be ready to go.