Why is she so good?

The old man regained consciousness and looked around in confusion.

"What happened?" he asked.

"Your heart problems acted up and you collapsed. How many times do I have to tell you not to get so excite? Are you trying to die and leave me behind?" the old madam wailed.

"But I feel fine, honey, looked at me, aren't I still here with you?" he asked. "I am full of energy." He attempted to leave the bed.

"What are you doing?" He Weili shouted worriedly. 

To their amazement, the old master climbed out of the bed and stood up steadily. There was no crouch in his back or moans about how his back was aching which was usually the case.

The old master even took a few steps on his own without needing a walking stick.

"See, I feel just as I used to when I was in my forties." He said. He even jumped up twice.

"How?" the old madam asked.