Stats upgrade the character's health and shield which help you stay longer in the game.
These are the amount of lives you have before you get to game over. If a meteor hits the character, your health goes down.
The amount of "Shield" that you have determines the percent (%) chance of not decreasing your health if hit by a meteor. For example, if your shield amount is 10, then you have a 10% chance to not lose a life when hit by a meteor.