Every true human being who specializes in the body and it's optimization knows that it starts with the mind. The body follows the mind. An unfit mental scape will always produce a flawed physical representation. Even when a person seems healthy and fit but is suffering from psychological trauma, the body will eventually manifest it. This is why it is important to feed the mind nourishing, effervescent material which will compliment your exercise regiment. There is nothing wrong with telling yourself the wonderful characteristics about yourself, even in the mirror.
Drinking water and other liquids throughout the day can keep you from becoming dehydrated. It can also help your muscles contract and relax more easily. It's especially important to replenish your fluids when engaging in physical activity and to continue drinking water and other liquids after being active.