Whatever you see changing about your body when you look in the mirror from day to day – looking fatter, leaner, bigger or smaller – is nothing more than water moving about. You cannot see real muscle or fat tissue gains or losses occur. They simply happen far, far too slowly; especially relative to the significant, visible movements of water.
The movement of water has no reliable relationship to actual tissue gains or losses. The perceived change can even be your imagination or distorted perception. Whatever you think you see, you could be right or wrong. Possibly nothing happened. Or the opposite could have actually occurred. Either way, in as little as a day or hour you can look different again and whatever did or didn’t change won’t be your actual body composition.
Given that you cannot accurately judge with your eyes what changes are really taking place in your body, the thing you should trust is real measurement! Regularly measure your strength, weight and body fat, and calculate the change in fat and muscle. That way you can make intelligent, objective diet and training adjustments according to what is really happening.
Of course, many people will argue that you should never measure anything and should trust the mirror and feelings instead. Their argument is that being ignorant is better than being informed. And their proof of this strategy is their own lifelong, steadfast devotion to absolute ignorance. I can’t argue. These people have a level of expertise on ignorance that I will never be able to fathom.
I recommend measurements because for every example of the success of an ignoramus, there are 1000’s of failures. And though measuring doesn’t guarantee success, I’d rather be an informed failure who knows exactly what not to do, than an ignorant failure who doesn’t even know it!