Changing your attitude is pretense - you cannot keep it up forever. The yogic system is about fundamental transformation - that is what ultimately counts.

Yoga is about shifting your investments from your body, mind, and emotions to your being – from imagination to reality.

Yoga is about living strong, not just eating vegetables, twisting yourself out, or closing your eyes.

Yoga is about rising to a new level of balance and competence in all aspects of life.  

Yoga is about attaining to absolute Balance, piercing Clarity, and an inexhaustible Exuberance. With this, you are immensely fit for life.