So remember: The bare minimum amount of activity to stay healthy and sleep well is 150/75 minutes of moderate/vigorous activity a week; double that amount if your goal is to lose weight.
To prevent corns and calluses and relieve discomfort if they develop: Do not wear shoes that are too tight or too loose. Wear well-padded shoes with open toes or a deep toe box (the part of the shoe that surrounds the toes). If necessary, have a cobbler stretch the shoes in the area where the corn or callus is located.
To get perfect finger calluses, one should play very regularly. You know you're playing a lot when your fingers really start hurting. Also, you should use what is popularly known as Eric Clampton's Secret Elixer which is nothing but rubbing alcohol. Just dip your finger in the alcohol. The alcohol dries your skin which later on hardens.