Arnold Schwarzenegger pushed the limits with his leg training. Today, you must do the same. These exercises are not about super heavy weight, but endurance to help cut the fat from your legs and reveal the sinew underneath.
Arnold said, "I learned something from all those sets and reps when I didn't think I could lift another ounce of weight. What I learned is that we are always stronger than we know."
Keep Arnold's words in mind as you train today. When your body tries to stop, your mind can overpower it. Finish the workout and be great.